BSA Gold Star "Union Jack" in .177, ongoing review

[Hubertus]

all bsa pcp are adjustable

you have to remove the hammer spring adjuster cover / anti tamper cap

sometimes its really tight

it is this cover

take a look at this shematic

now you can adjust it with a big flat screwdriver / tool

 

[bfloyd1095]

Here is a short , informative video for those of you that may not have seen it

https://www.youtube.com/watch?v=yNQ-38UQR_k&t=182s

 

[Franklink]

Great info! I appreciate the schematic AND the vid showing the hammer spring adjust. I was not aware that the power could be changed, so that is nice to know. There is no mention of it in the manual, nor was there any discussion on the UK forums. I thought I dug pretty deep but in hindsight I realize it makes sense that they wouldn't discuss upping the power, since the guns over there are limited to 12fpe and likely tamper-proof. 

As far as whether or not I'll mess with upping the power now that I know about it..........I likely wont, for a couple reasons. First, it's a borrowed gun. Second, the 8.44gr going 920-940 has an enticingly flat trajectory. Third, I'm wanting this review to be somewhat of an out-of-the-box report. There is a lot of appeal (for me at least) to the idea of being able to simply remove a new gun from it's box, and have it perform at a high level without any tinkering, tuning, etc. (Seriously, at this point, I haven't even put any kind of cleaning agent in the bore, just passed a very small number of patches through it, dry. Have not removed it from the stock. Have yet to adjust the trigger either. It's thus far been a pretty much, shoot-it-as-received experiment, minus adjusting the stock to fit me and putting a moderator on it).

So, I may get around to upping the power another couple FPE, but likely not. I'm kinda lumping that together with polishing up the crown and doing the JB process on the bore. (Things that I might want to do if I owned the gun, but would definitely get permission from AOA before performing). 

I just got back from shooting it at 104 and 78 yards. That's a LOOOONNG ways out there for 8.44gr pellets @ 16.5 fpe. What a hoot! I also shot ten over the chrono before I left since the gun has sat for 6 days without being shot-wanted to see what that regulator does after sitting. I'll report on all that later when it gets dark. Daylight and not at work = shooting time, not computer time. 

It looks like I'm going to have a chance to do some BC testing this afternoon. And the weather and my work schedule are looking favorable (high winds projected) for Mon and Tues, so the wind deflection tests may happen early next week. 

 

[Franklink]

I shot the Gold Star today, for the first time since Saturday (six days). I own a completely different gun that has a low fps problem when the it goes a few days without being shot. From that gun, the first shot is always 50-60fps slow. As long as I remember that, no problems with hitting what I want, but it's a small annoyance. 

So, I chronographed the first 10 ten shots this morning, after it's six day break. Those results: Average = 923.8fps, ES of 19.88, and SD of 5.74. This was with the 8.44gr JSB that I decided it likes the best. So, about the same power it was doing when I put it away, but most importantly, the first shot wasn't extremely low fps. Nice to know the reg is stable enough to behave on the first, cold shot. 

POI was dead on too, which is important for those of us that like to be able to count on a gun to put a pellet in the same place today, that it did 6 days ago. 

 

[Franklink]

I had to run an errand this morning and noticed the big flag was hanging as limp as I've ever seen it. On the way home I decided to throw some gear in and see what 16.5fpe can do at longer range. Yes, I realize this low power is not practical for much more than 55 yards. But, "not practical" can be applied to a lot of airgunning. So, practical or not, I knew it'd be fun and I decided to give it a go. 

My little helper wanted to tag along. I like to get in the back of the truck to elevate my pellet path above a lot of the ground cover, but I knew from past experience that setting up in the back of the truck with a two year old also in the vehicle doesn't allow for the most stable shooting platform. Doesn't look like much ground cover right here in the pic but it's further out. You can just make out the box at 104 yards in the upper left of the image, just to the right and in front of the juniper tree (bush). 

Right about the time I got all set up, the wind came up. It wasn't crazy, but too much for 8.44 gr pellets at 104 yards. The nearest weather station recorded "calm" for the times that I was shooting, "calm" my butt. I was watching the lid on the box flapping in the breeze through the scope while questioning my sanity in even attempting such a feat. 

Needless to say, it didn't go well at 104 yards. I could barely keep them on the paper. 

104 yard results:

 

Can't win them all.

Bottle cap for perspective just cuz it was handy. I've shot enough at distance to know this, but how much a cross wind can lift or lower the poi never ceases to amaze me. Wind currents are always doing a lot more than just traveling horizontal to the ground like they feel like they're doing on our skin. 

At this point, I decided that something a little less lofty might be in order, so, rather than head home with my tail between my legs in sheer and utter defeat.......I moved the box in. 

This went much better and renewed some of the self-esteem that the 104 yard attempt had stripped away. 

78 yard results. 

I can count 18 shots on here. The five shots to the left is where I was holding for all 18 shots, but those five happened to go downrange when there wasn't any wind. The 13 shots in the 1.75 inch group mostly centered, are where the breeze was carrying most of the pellets. Vertical effects of the wind can be seen here too.

It won't be winning EBR, but to be able to at least put a group together, that far out, and with such a low power airgun, it helped to bring me up from where I was with the 104 yard attempt. 

Those 13 are all within the center mass of a starling. And all 18 are within the center mass of a pigeon or Euro dove. To be able to hit a pest bird at nearly 80 yards with a 16.5fpe airgun, fairly repeatably, well, I thought it was pretty cool. (Chairgun says 5.97fpe left at 80 yards, so, would easily kill those fictional pest birds I referenced). 

So, practical for something like EBR? NOPE. Practical for removing some pest birds that far out?.......could be done.....and they'd never have known what hit em cuz this is NOT a loud gun. Realistically, should probably try to scoot up a little closer to the pest birds though. Fun? Heck yeah. 

 

[Franklink]

In the past few days, with all the thoughts of the cold hammer forged BSA barrel, and the rifling marks imparted on each pellet from various barrels, and "taking less wind," I noted that I wanted to measure and compare the BC's from a couple of my own guns to the BSA. Today that happened.

FPS in table are ten shot averages. For the non-regged guns, the shots were taken with the pressure right in the middle of where I know the hi and low pressure need to be for consistent fps. This was to avoid scenarios like the far shot fps average from being taken from down the far side of the bell curve of the shot string ( which would equate to lower fps just by virtue of the tune and have nothing to do with fps lost due to distance traveled). 

So, there is a lot of data in that table. 

The outlier is the poly barrel, because it is the most disparate rifling profile from the other two, but also because it is shooting a little hotter. That poly barreled gun is my primary FT gun, and I'm not willing to go messing with the fps and losing all my scope data for the purpose of this experiment. 

All three barrels were first tested with the exact same JSB 10.34 pellets. 

• The calculated BCs were slightly different, from each of the two calculators that I used. 
• To get Strelok data to most closely match actual trajectory, I would have to say the BC's from the Chairgun BC calculator are more accurate than the calculator on AOA's website. 
• I expected the BC from the poly to be better, but also by a bigger margin than I measured today (based on real world experience with this barrel, slightly higher fps, and less pellet distortion with the poly). I'd love to see the programming behind these two calculators to compare the math formulas they're using.
• Hardair doesn't have a listed BC for the JSB 10.34, they list some JSB 10.3 "ultra heavy shock" or something like that, but not the "Diabolo Exact Heavy" (I said, "Huh, seriously?" to myself a couple times about how the such a "comprehensive" BC database could be missing this pellet. Anyway.) 

I then tested the two most similar barrels and power level guns, with JSB 8.44 pellets. 

• I laughed to myself when I saw how close in power these two guns are set up. That is completely by happenstance. 
• The BSA CHF barrel did indeed have a slightly better BC here. Because of this being a gun from the UK, it almost makes me wonder if the bore diameter, rifling profile, etc were optimized for this weight of pellet. An 8.44 is the more logical choice when shooting a 12fpe rifle like they mostly do in the UK. 

Overall, the measured BCs are better than the published values. This is common across all my guns and I attribute most of it to the thinner air at the 5600 feet where I live. I understand that BCs are not static and are not the end-all be-all, but I'm curious to know if the BC from the cold hammer forged barrel could be improved with some barrel polishing. Both of my personal barrels have been massaged to get to where they are, much JB bore paste, applied in a very specific manner. The out-of-the-box BSA cold hammer forged barrel has a better BC than my carefully polished barrel (with the 8.44gr pellet, which also happens to be the BSA's preferred pellet). It just makes me wonder if there are some gains to be had there with a little bore polishing. 

So, what real-world effect does all the BC testing have? Honestly, not much. All guns shoot how they shoot. KNOWING BCs and sciency stuff does not change the accuracy that the gun is capable of. Interesting? Yes. But what means more to me is when I put all the paraphernalia away, put the two personal guns where theyre kept, moved the chronograph back to it's storage place, and plop down on a bum bag, with just the gun and some pellets, and put pellets in the previous pellet's hole at 30 yards, and nearly do the same at 55 yards. That is the part of air-gunning that can make a grown-a$$ man giggle with excitement. 

Now, for something on a lighter note......How did I manage to avoid shooting my chronograph at 53 yards, shooting pellets that the gun's don't like? Well, like this:

 

That C-shaped steel piece is from a non-airgun-related project. It's probably 7/8inch steel. Weighs a ton. Ain't no pellet getting through that. All the extra pellet hits on the white painted steel C are from a different shooting session. The little rock sitting on the lip is so that I can line up my shot with the chrono eyes. The traditional LW barrel HATES the 8.44 gr pellets-sprays them everywhere. I actually accidentally shot my little alignment rock off with those non-preferred pellets. 

 

[steve123]

It'd be neat if you could use a timer and fire two guns at the exact same moment, need two shooters of course - (is your wife a good shot??) and see how those two guns 'take wind' as a comparison.

Man you are putting a lot of work into this....

 

[Franklink]

It'd be neat if you could use a timer and fire two guns at the exact same moment, need two shooters of course - (is your wife a good shot??) and see how those two guns 'take wind' as a comparison.

Man you are putting a lot of work into this....

That WOULD be a very clean comparison, with each pellet going through the exact same wind currents. Sadly my wife won't humor me. 

I'm still planning the design out in my head, but so far thinking of doing multiple ten shot groups, each gun gets it's own corresponding aim point, let the wind do what it wants to the pellet (no hold off). Do that a series of times, lay the pages on top of each other to find an average point of impact vs point if aim to arrive at a sort of cumulative wind deflection for each gun. 

It's not work if I'm having fun! (Shooting it right now actually. No data collection or comparisons, just enjoying the gun. And it is a very enjoyable gun to shoot!) 

 

[Arzrover]

When LD and I tested barrels at his place, we measured the max deflection and also the range of deflection. The wind changes almost constantly at his place so a 10 shot group would be "x" inches wide with a min and max from aim point. Interesting results. We had previously had a debate about wind sensitivity as my factory barrel on my USFT was quite bad. I took 4 barrels fit to my USFT plus my best wind rifle(sub 20 ft lb) which happened to be an RN10 doing 13 ft lb w JSB 8.4s . He broke out a couple of his favorite match rifles. When all was done, the RN10 and the poly I have on my USFT proved to be the best..... least max deflection and smallest range....... also smallest vertical. He had a couple that were right there but the one issued w my USFT was about 3 times as bad in the wind. Keep in mind, he has a 51 yd tunnel to set zero. The barrel on the RN10 has a 12 groove w very fine rifling. Must be PERFECTLY symmetrical. The differences in accuracy between them all weren't huge in the tunnel.

Testing the BC ..... SHOULD yield similar results. I need to make a note to do that.

Fun stuff

Bob

 

[Franklink]

Thanks ArzRover. That certainly got the wheels turning in my head, as I was mostly thinking of horizontal dispersion. Yes, vertical dispersion is just as important and it should be interesting to see. 

With my idea of laying the pages on top of each other, I was thinking of backlighting them, similar to viewing an x-ray. My thought being that a greater number of shots, taken over a larger time frame during a windy day should give a more accurate representation of the barrels wind-bucking abilities, AND also remove the chance of shots taken during a favorable few minutes of lessened winds, indicating a false-positive for a certain barrel. Basically, spreading the groups collected over a greater amount of time.

It all sounds complicated but the question I'm looking to answer is simply: does the BSA CHF barrel in this Gold Star offer a wind advantage like the particular barrel Mr Lait has in his Gold Star.

 

[Franklink]

Wind deflection testing.......

Didn't happen in these two days off from work. The wind at my house usually comes in from a southeasterly direction. My range shoots into the northeast corner of my property. There is a six foot fence all the way around the back yard. With the normal wind direction, it has a chance to go over the fence and get back down to ground level before it hits my shooting area. So, I end up with crosswinds at ground level. But, not the wind yesterday and today. Yesterday it was from the east and today it was from the north. So, the fence actually protected my shooting area quite a bit in the last two days. I watched my little make-shift wind flags like a hawk, actually hoping for unfavorable air currents on my shooting range, and they never materialized. So, the testing of the BSA barrel in the wind WILL happen, just hasn't happened yet. 

Handling

I did spend a large amount of time shooting the gun in these last two days, and want to share how I feel about it's handling characteristics. I finished a complete tin, as well as the initial 80% full tin that I started with. Including the pellet testing, I'd guess that I've got about 1250 pellets through the gun now. So, here are my thoughts, at this point in my experience with the gun:

• The bolt started out tight (bordering on stiff) and is now smoother to operate, but it is still evident that there wasn't very large tolerances designed into the gun (no slop in the bolt mechanism ). I'm not talking about the force to cock the gun, but rather the hole in the breech in which the bolt rides is only minimally larger than the bolt itself (ie, opening and closing the bolt doesn't feel like putting the oil dipstick back where it goes in an engine, bouncing from side to side and scraping here and there).
• The safety does not auto-reset, and that's a good thing. (I hate auto-resetting safeties). It's nice to just cock, load a pellet, and shoot. 
• This might be the first gun (airgun or otherwise) that I've shot that cannot be loaded from the right side. 
  • I mentally went through the gun cabinet and NEARLY everything either loads or ejects from the right side. The outliers are a single shot, break action center-fire rifle, an airgun that allows loading directly into the rear of the barrel, and an airgun that can be loaded from top, right, or left (Taipan Veteran). Nothing loads from ONLY the left side like the BSA.
  • I initially was thinking this was a negative but I've kinda come around to the idea. It actually makes better sense than I'd have ever realized if I hadn't spent some time shooting it. Whether from a bench or a bum bag, the right hand/trigger hand, can stay on the grip, while the left hand does the loading. It equates to less switching of hand positions and I think I like it now. So, other than muscle memory fighting a guy, the left side might actually make more sense than the right side. 
• The stock has a flat to allow an upright thumb position. With various guns, I've found that I have better trigger control when I leave my thumb upright, versus wrapped around the grip, so this is a feature that I very much like. 
  
  
• Another aspect of the gun that has grown on me is the curve in the bottom of the hamster/knee riser. My personal FT gun has a flat knee riser and I like it. When I first saw this one I thought to myself, "that curve could be interesting to work around." Come to find out, when the stock is adjusted just right (lop, etc), that curve fits the curve of my knee and allows the gun to be sorta locked into position with a little forward pressure.

• The stock feature that I cannot get used to or grow to like is the forend. It has an aggressive taper from just in front of the knee-riser to where the forend stops. I like the visual lines that this gives the stock, as it's rather aesthetically pleasing, but it's less than convenient for handling. The instances where this is a problem are when the gun is being carrying vertically (through doorways) or when it is being placed into my gun cabinet. Again, this might be a muscle memory thing, but I've found that I tend to hold onto a gun with my left hand on the forearm when it needs to be carried vertically. That angle leads to a quickly vanishing stock. That and gravity combine to make it feel like it's going to slip out of my grip. (possibly just paranoia that I'm going to drop a borrowed gun here, but every time I have to hold it by the forend in a vertical position, I slightly panic that it's going to get dropped). 

• I'll eventually get around to reporting on how it handles from offhand and kneeling positions, as well as any further thoughts I have on shooting it from a bench or bumbag (field target) position. 

 

[Franklink]

Trigger

In my initial post I noted that the trigger has a lot of first stage and then breaks fairly easily, going to build on that now that I've had some more time with it. 

I shot about 1250 pellets before I decided that I would like it to break a little lighter. So, a little internet searching and revisit of the manual. Here is the guidance provided by the manual:

When first inspecting the gun, it would seem that the trigger adjustment screws could be accessed through the trigger guard, as there is a nice open slot. 

 

but that isn't the case. Even with the big open slot in the trigger guard, only the finger pad rotation screw (screw #5) can be accessed without removing the stock. Screw #2 is visible, but it has a lock nut that makes adjustment through the trigger guard nearly impossible. Additionally, screw #4 cannot be accessed without removing the action from the gun, despite the manual saying the opposite. Screw #4 can be seen here, the Philips head that is recessed into the stocks trigger slot. Trying to get to that screw without taking the action out would surely booger up the beautiful stock. 

Since I wanted the break to be just a hair lighter, and it seemed that would be screw #1 (which is not even visible through the trigger guard), I surmised that the action would need removed from the stock. 

The hamster/knee riser has to come off first. The top hole here allows the knee riser to be adjusted for height, via supplied Allen key, and also backed out enough for the knee riser to be completely removed. 

This plate is what's under the knee riser. Plate is removed via those two screws. They are machine screws, threaded into the next metal piece. 

The metal piece where the knee riser posts are fixed has to be removed with the two longer wood screws. Once all that is removed, the large, blued lug bolt (that holds stock to action) can be removed. The lug bolt is also an Allen head. 

This is what you're left with.

I was surprised to see E clips and the thick steel plating on both sides of the trigger group. Fewer overall parts, but the forward/aft and rotation adjustments for the blade, as well as the steel plates, and E clips, are all quite reminiscent of a FWB 300s trigger group. 

Short little video of the trigger in action, if you're into that. 







https://youtu.be/cX6nvN9DPPs







So, ultimately, I backed out screw #1 about 1 full turn. I also slid the trigger blade back, as I felt I was reaching a little for it. I also rotated the trigger blade slightly. Those adjustments to the blade can be seen in the first two picks of this post. I would assume the break could be further lightened by adjusting the manual-forbidden screw #2. I'm also guessing that some of the long first stage could be remedied with adjustments to also-forbidden screw #3. Some judicious polishing would also likely further improve the overall feel of the trigger.

The trigger guard is metal, but not magnetic, probably aluminum. 

The trigger blade is plastic. I forgot to note what the rail that the trigger rides on is made of, and I'm not willing to go back in to figure it out. That rail is plastic on the FWB 300s guns. 

So, my opinion on the trigger. 

• The big slot in the trigger guard seems ill-conceived. I don't see the point, since only one screw is accessible.
• Props to BSA for the metal trigger guard, but the plastic trigger blade is a bummer. 
• Access to the trigger adjustment screws is pitiful, and getting the stock off requires going through all the knee riser hardware. That's a lot of effort to simply adjust the trigger screws. 
• The "feel" of the trigger ranks up there pretty high, with guns that I own or have had the pleasure to shoot. Better than a Marauder trigger, even a well-adjusted one. Not as good as a USFT trigger, but not many are. Much better than a gen 1 Raptor trigger. Pretty comparable to a gen 2 Raptor trigger, as well as a Taipan Veteran. It has a little bit of that clicking-a-mouse sensation of an electronic trigger, like the Red Wolf. It is not as good as a Daystate electronic trigger, but I compare it to that because I can't feel any of the linkages or leverage points that make up the trigger like I can with other mechanical triggers, even good ones like the Vet and the Raptor still allow me to feel those components.
• More on the "feel." It is extremely predictable, in that there is no guessing when it is going to break. The break point is also very crisp, no mush and no through travel. 
• I'd guess that it's more than 1/2# but less than 1#. It likely started around 1#, before I adjusted screw #1.
• A very good trigger, capable of extruding the accuracy that the barrel is capable of. 
• In summary, I like the trigger enough as-is that, even if I owned the gun, it would be left right where it is, as far as adjustments and further tinkering (polishing). 

 

[fderry]

Franklink

Thank you for this review! I really enjoy your detail and pictures. I noticed your initial picture showed the rifle with the stock air stripper and you said you might test with it attached if noise wasn't a factor, but subsequent photos show the rifle with a moderator attached. How loud is the rifle with the air stripper and will you be testing the rifle with the air stripper attached in the future? The reason I ask is I'm curious if a tuned air stripper really aids accuracy on this rifle. 

 

[Franklink]

Franklink

Thank you for this review! I really enjoy your detail and pictures. I noticed your initial picture showed the rifle with the stock air stripper and you said you might test with it attached if noise wasn't a factor, but subsequent photos show the rifle with a moderator attached. How loud is the rifle with the air stripper and will you be testing the rifle with the air stripper attached in the future? The reason I ask is I'm curious if a tuned air stripper really aids accuracy on this rifle.

I'm glad that you're enjoying it. I am sure having fun spending time with the gun. 

Short answer: yes, I am still planning on comparing accuracy with the stock air stripper, both against the moderator, and with various stripper cone lengths. Roger Lait from the UK told me that he tested with various stripper cone settings and never saw any change in accuracy, but I'm planning on playing with it anyway. 

Long answer: I still have a handful of tests and comparisons and results with this gun that I am planning on reporting. I initially told AOA that I'd like to spend a lot more time with it than a normal reviewer, going deeper into the gun and it's performance than we usually see (eventually even competing with it). So, for now, planned reports on the gun include the following:

• the aforementioned stripper vs mod tests (To answer your question-I'm not sure how loud it is with the stripper, as I went straight to the moderator. This test might include some decibel readings.)
• accuracy from the magazine vs single fed pellets
• chronograph results (I've commented that I wanted to compare chrono results of a "broken in" reg versus how it behaved when new, so this report will likely be towards the end of my time with the gun. Mapping out the point of impact over 10-55 yards still shows the gun doing a pretty consistent 930fps like it was when I first received it).
• barrel cleaning/lubed pellets
• fill port/gauges (this will likely be a short one, but there are a couple things I want to share about it)
• wind deflection testing against a couple other small caliber 16-19.5fpe guns
• I want to share some more groups from the gun, as I don't feel like I have done much of that
• Field Target (this will be one of the longer reports still left to do)
  • I've mapped out the initial point of impacts from 10-55 yards and verified them a couple times. That process (and it's results) will be shared.
  • I will compete with it in at least one of our monthly Field Target competitions. Any comps in which I use the BSA will also get a report, with pics and results. 
  • Most of my shooting with the BSA has been from a bum bag, which equates to pretty good practice for taking a gun to a match. Initial thoughts in that regard are that it is a very pleasant shooting experience, from a bum bag in a FT scenario. Stable. And accurate. Hole in hole out to 20 yards if I range right, 3/8-1/2inch groups at 30, and I can keep em under an inch at 55 (when the wind cooperates or I read it right). 

Lots more fun to be had, and I'm planning to continue sharing it. 

 

[Franklink]

Air stripper vs moderator

I planned to test accuracy with each today but the stripper is just too loud for my home range, for various reasons. I shoot from inside the garage and it was loud enough to hurt my ears, but also loud enough that I was concerned with annoying the neighbors. 

So, I have another place that should be more appropriate, I'll try to get over there and do some accuracy comparisons, but I did take a few decibel readings today that I'd like to share.

Situation: decibel meter app on my phone with phone placed 2ft in front, 6 inches below, and 1.5 feet to the side of the muzzle. I shot a couple shots with moderator and with air stripper. 

Moderator: 73 decibels (Hogan Decimeater-1.125in diameter and 7.125in long)

Stripper: 76 decibels

I was aware that the decibel system scale is wonky but learned a little more about it this evening. CliffsNotes version: the organ system that comprises our ability to hear and process that sound(auricle/pinna, ear canal, tympanic membrane, ossicles, cochlear nerve, auditory cortex, etc) cannot recognize linear changes in amplitude. It can recognize SIGNIFICANT multiplying of the loudness of a sound. That's the background for why the decibel system is a logarithmic scale. Lots more to learn about with a simple Google search, if interested. 

The relevant part I want to point out, is that 73 vs 76 decibels makes us think, "ah that's not much difference." BUT, a 3 decibel increase means the sound is TWICE as loud, again, due to the logarithmic scale that is the decibel system.

The stripper is LOUD. 

 

[Franklink]

Single feed vs magazine: 

4, ten shot groups with single shot tray, and 4, ten shot groups with the magazine. Taken at 52 yards. Alternating (ten shot group with single shot tray, then ten shot group with mag). 17-21mph right to left winds.

Trying to account for the wind here (timing shots between gusts, holding off, praying hard, etc).

Biggest circles are 1 and 5/8 inches.

Hold-offs were between 0.5-1 mil. Interesting to note the horizontal stringing from the wind. 

The average group size is bigger with the magazine, but this really needs to be retested when the wind isn't screaming like it was today. 

 

[Franklink]

Wind deflection:

For those that have not been following or perhaps got lost in the excessive details, a few weeks ago I pushed some pellets through various barrels to compare imparted rifling to the BSA cold hammer forged barrel. In that discussion I decided to eventually do some wind deflection tests. That happened today.

The general idea was 10 shot groups at 52 yards, holding dead on the aimpoint. I did not try to time shots with lulls in the gusty winds, nor did I hold off to account for the wind. The winds were 18-21 mph today, per the National Weather Services station about 20 miles away. Winds hit my target area from the right to the left. First 10 yards of pellet travel is from inside the garage, another 5 yards of house protects the flying pellet. Then they are open to wind effects from 15 yards out to 52. There is a stack of firewood for the last 10 yards that the wind goes over and then sometimes has the effect of pushing pellets down, in addition to the right to left. I have seen discussion that suggests the wind nearest the muzzle has the most effect on pellets. That may be true, but I've found that any wind, anywhere along the pellets flight path WILL affect it.

This is the target used for the experiment. LW traditional rifling was always on top, LW polygonal in the middle, and the BSA cold hammer forged at the bottom. The gun with the traditional LW spits the JSB 10.34 out at an average of 880 fps (about 17.5fpe). The LW poly is doing an average of 926.6fps (about 19.7fpe). The BSA also average 880fps. Blue dots were the aim points. Largest circles measure 1 and 5/8 inches. Groups were measured center to center, and horizontal deflection measured from the aim point to the center of the hole.

On the first target I used the pellets that the guns prefer. So that meant JSB 10.34 for the LW barrels, and JSB 8.44 for the BSA. I then realized it wasn't quite an apples to apples comparison with the BSA using lighter pellets. The 10.34 were the second-best pellet in the BSA, and it shot them pretty good during pellet testing, so I decided to complete the experiment with 10.34 for all three barrels. Interesting to note that the largest BSA group came from the 8.44 on this target (1.662 inches). Maybe I need to rethink which pellet the gun prefers, at least in the wind. Really cool to see how the 8.44gr pellet group with the BSA was so stretched from the wind, very little vertical dispersion but it really grabbed some of those shots and yanked them to the left. That would be the ballistic coefficient version of a picture is worth a thousand words. This target didn't go into the calculations for the average group size or average horizontal dispersion, but I'm including an image for the value of that visual representation of what the wind does to a pellet with a lower BC. 

So the above described scenario was repeated 6 times, so, 6, ten shot groups from each gun. All the rest of the groups were shot with JSB 10.34, from all three guns/barrels.

Here are those six targets (best attempt at similar cropping was made to keep the scale similar, because of the scale, the groups SEEM to be larger than they actually are):

This one has the best poly and the best hammer forged group sizes (0.619 and 0.875 inches, respectively). Interesting to note that the wind must have been better right here, since two of the guns shot their best groups on the same paper. Although the traditional LW shot it's worst group here, at 1.986inches, mostly due to the wind really throwing one of them to the left. That pellet is the maximum horizontally deflected pellet of the entire testing, at 2.077 inches to the left of the aim point. 

This next one has the best LW traditional group, at 0.962 inches. It also has the worst poly group, at 1.62 inches.

Another very good BSA group on this next one, at 0.952 (very good for the conditions).

Pretty good group from the poly barrel here (0.96 inches):

None of the best or the worst on these last two.

On this one I got lost on the reticle for one shot with the traditional LW (shot went high).

Through all of them, there are a couple human errors where I pulled right. Overall though, I was pretty on my game today, and most shots broke with the crosshairs or correct holdover on the aim point.

After all that, I sat down with some calipers, for a very long time. I measured all the group sizes, as well as the horizontal deflection. EVERY. SINGLE. SHOT. It took forever. I had plans to do the vertical too, but lost some motivation with as long as the horizontals took. The plan was to be able to pinpoint the single x/y average location of all the shots taken. I settled for just figuring out the average horizontal (distance to the left of the aimpoint). The average horizontal deflection was simply taken by adding the distance for every single pellet hole, and dividing by the number of shots.

The average horizontal deflection (measured by distance between center of pellet hole to the line bisecting the aim point) was:

0.963 inches for the LW traditional

0.627 inches for the LW polygonal

0.924 inches for the BSA cold hammer forged.

The blue lines here represent those three average distances (horizontal deflection) from the line bisecting the aim point:

The average group sizes (again, ctc) were:

1.56 (1.5647) inches for the LW traditional

1.16 (1.1598) inches for the LW polygonal

1.17 (1.1683) inches for the BSA cold hammer forged

Discussion:

Pellets were pushed by the wind less with the poly. This gun has always been impressive in the wind. It is quite possible that the difference in deflection is simply because this gun is putting out about 2 more fpe than the other two. The important thing to note is that this barrel, even with the extra 2fpe, did not have a significantly better ballistic coefficient when that was tested a few weeks ago. The only way to PROVE that the poly profile does better in the wind would be to reduce the power output to be more similar to the other two guns. I'm not willing to dig that deep. For this experiment, I'm satisfied to know that the poly simply did better, with the guns in their current configuration. I personally suspect it is because the pellets are so minimally deformed by the poly rifling. There just isn't much there for the wind to catch and grab.

The BSA barrel did better than the LW traditional rifling, both in average wind deflection and in average group size in the wind. The BSA average wind deflection is very minimally better but the average group size is 0.4 inches better with the BSA than the traditional LW rifling. 

Perhaps the biggest pro-BSA finding is that the average group size (in windy conditions) is only 0.01 inch (depending on how I round) worse than the average group size from the poly. The biggest poly group measured 1.62inches and the smallest was 0.619. The biggest BSA group was 1.462 inches (with 10.34gr pellets), and the smallest was 0.875. The poly barrel is on a Field Target gun with a track record for having the potential to win matches. It has shot a perfect FT score, as well as commonly only had 1 or 2 missed shots in various field target matches. The poly barrel is a very good one. The BSA is right there with it, in average group size in windy conditions.

Taking all of that together, the BSA cold hammer forged barrel averages a little greater wind deflection than the poly with a proven track record. BUT, the BSA cold hammer forged barrel shoots nearly equal average group sizes as the poly, even with the BSA doing 2fpe less than the poly. So, the poly groups them closer to the aim point, but the BSA and poly barrels will both print nearly equally sized groups, in nasty wind conditions. 

And remember, these JSB 10.34s were the second most accurate pellet in the BSA. In windy conditions, the 10.34 would be the choice for the gun for sure, but it actually shoots more accurately with the 8.44gr pellets (in reasonable winds). 

For it to stand toe to to with the poly, I'm more impressed with the cold hammer forged barrels performance in the wind than I expected to be.

 

[Franklink]

Field Target (but first a leak)

All of the getting to know the rifle has been/was with the intention of competing with it in a field target match. The Airgunners of Arizona are having a match tomorrow morning. I actually should be in bed but I'm staying up for a little while to make sure that my reseal of the gun is going to hold air. Yes, there's a back story there.

I was getting things all gathered up so it'd be an easier early morning departure. Upon removing the gun from the gun cabinet, I had that PCP shooters moment of dread when we realize there is a lot less air showing on the gauge than there was when the gun was put away. Quickly thought to myself that maybe I was remembering wrong, so I hooked up the tank to top it off. I could HEAR the leak. Oh no! I could tell that it was coming from the fill/gauge area. I remembered reading that someone commented online somewhere that his gauge just needed snugged up. No dice, still leaking after the snug up. Hmmmmmm. Maybe it's just the orings on the fill probes-I've found those little guys are easy to cut when inserting the probe. Replaced those. No dice, still leaking. So, further disassembly required. First off, I never intended to need to go this deep, but with a match tomorrow morning, dangit I want to shoot the gun at the competition.

So, that lead us to this point:

Nice to see a little sintered filter in there to keep crud out of the gun. The little pin holds the check valve spring under tension. Gauge and end cap are out of place in this pic-they go on the left side of the brass piece. (Also realized the air volume is even smaller than I initially thought, that little air tube is very SHORT, the reg on the other end taking up room). 

Couldn't find any debris or any poor looking orings. Put it back together.....still leaking. 

At this point I'm still thinking the gauge might be the culprit, but then I realize the air is coming from the area of the red arrow, vs the area of the green arrow.

That little blued portion has flats for a wrench, underneath I found a mangled oring. The oring the red arrow is pointing to is not an air sealing oring, but rather the oring that the fill port hole cover rides on for an interference fit. But, there is an oring not visible in this picture, that DOES seal air, right under the red arrow.

I dug through my oring stash and luckily had something pretty close.

The 016 was the one that hopefully is going to allow me to compete tomorrow morning. The 018 was used to replace the oring that the fill probe hole cover rides on (the one that IS visible in the pic). 

Back to Field Target

For a guy to do well at a FT match, they really need to know a gun. That means spending lots of time shooting it. In the past few weeks I've reported all kinds of tests and comparisons on the gun, but I've been pretty quite about the FT work-up that's been going on behind the scenes the whole time. 

I'm sure everyone has their own process, but once I've figured out what pellet a gun likes, got it adjusted to my preferences, done the chrono work, zeroed the scope, got to know how the trigger feels/behaves, etc, I like to actually shoot the gun at targets at all the distances that I might see a field target set at in a competition. That means 10-55 yards. Some guys just like to go off ballistics programs info, but I like to shoot at real-world targets at all the distances. This is a tedious process, but it builds confidence in the dope data, as well as constitutes practice, in and of itself. The added benefit is that getting up and down to move pellet traps back and forth, approximates the action of getting up and down from one lane to the next, with the accompanying increase in heart rate. 

While I don't like to rely on ballistics programs, I still like to compare to them.

My initial trajectory mapping gave me these numbers. Strelok predictions provided as well. I honestly care more that my numbers for the scope clicks will hit my aimpoint at the corresponding distance that I have a marked for "clear" through the scope much more than if my scope marks are right. With the way I do it, I could put A, B, C, D, E, etc as focus points on my sidewheel and still be okay, because my click values correspond with that value on my scope wheel. 

Once I have those initial numbers, I like to verify them at various temperatures and conditions and times of day (lighting effects on scope ranging). Once I have them verified and finalized, I'll print them and shrink them down and tape it inside the scope cap. 

Here is one of the trajectory verification sessions a few days ago. Yep, slushy rain that was really wanting to be snow. Buckets a yard or two from each other. Again, shooting from inside the garage so nice and dry for me and the gun.

As far as the gun has done......absolutely perfect. Misses are me, not the gun. When mapping out the trajectory I like to make dots with a sharpie marker. The dots are roughly the size of a .177 hole. This allows me to see if I'm not centering the hole and need a click or two more or less. 

Here is one of those practice papers from the soggy day. The gun will perfectly center the sharpie dot when I don't pull the shot or range wrong.

Furthermore, the gun has held it's zero from the first shooting session. The scope I use has resettable turrets. They have not needed changed since day 1-still perfectly zeroed. The gun has been cleaned, taken out of the gun case numerous times, moved to and from my shooting area, taken a truck ride or two, etc, and nothing has messed with the zero.. That is a very desirable trait for a FT gun, where we rely on KNOWING the trajectory. Constantly chasing a wandering point of impact would be an entirely frustrating experience. It will be interesting to see if that all holds true with the reseal. I'm hoping I didn't torque the scope at all in the removal of the air tube. 

I also use a paper target called an International Field Position (IFP) target for FT practice. 25 shots at 30 yards from any field target position. (I shoot "Open" from a bumbag with a shooting harness) 50 points possible, 2 points for clean inner circle, 1 point for clean outer circle, 0 points for outside of the outer circle. I recently realized that the master I've been using is actually shrunk down to be even harder than the IFP rules specify-gotta be under 0.337 for a 2 and under 0.737 for a 1. 

This is the first four IFP targets shot. 

High 30s are very respectable for an IFP, especially one where the circles are smaller than the initial rules specified, and the 42/50 was where I was stuck with my personal FT gun for a long time (I've since gotten a 43 out of that gun). I was able to get a 42/50 with the BSA on the fourth try. I've since shot others, but usually the high 30's are where I'm at with the BSA.

I've also practiced a little for the offhand and kneeling shots. This is 25 shots at 30 yards from about 50:50 offhand:kneeling. About ten of them dinged the cube target (KZ hits) and 15 of them hit the faceplate. Kill zone is 1/2 inch on this I believe. That's about normal for me and my lack of offhand shooting abilities. The gun shoots nicely offhand and kneeling, those forced position shots are just my weakness. 

I found out tonight that gun needs a large case, when the knee riser and cheek piece are extended.

Well, it's been two hours since the reseal, gun is still holding air so I'm gonna hit the sack.

I'm intending to get some pics of the match tomorrow and report how the gun performs 

 

[Franklink]

Field Target Match

Well, after 4hrs of sleep, the Gold Star was still holding air, so I headed to the match and had a great time.

Before I get into how the gun performed, I'd like to give a little intro to FT, for those that have not had the pleasure of shooting in a match. Since I will be using many of the pictures that I screen-grabbed from past match reports, I need to give credit to our club secretary, Mark. He goes by Mark.in.AZ here on the forum. He is our jack of all trades, an accomplished photographer, designated match report writer, and match director for many of our monthly matches. He puts in lots of time and effort and he is greatly appreciated. Thank you Mark. The majority of the pictures I am using here were taken by him.

FT is a game of not only precision, but the ability to repeatedly replicate that precision. Steel targets are placed from 10-55 yards, consisting of a (usually) animal shaped face plate and with a round kill zone (hole) in the faceplate. Distances are unknown and most shooters use their previously marked sidewheels to "range-by-focus." Meaning the scopes ability to be focused at a certain distance is how the shooter guestimates how far out the target is set. Hitting the animal, or missing the target entirely, awards the shooter zero points, and the animal stays standing. BUT, placing a pellet inside the kill zone trips a paddle that causes the target to fall backwards, or sometimes to the side, signaling a point-winning hit. The kill zone sizes are various sizes, usually 3/8" at the smallest, and 1 and 7/8" at the largest. Kill zone size determines how far a target can be placed from the shooter and still be considered a "legally" placed target. Smaller kzs up close, and larger ones further back.

A man named Brad Troyer devised a numerical system by which each target can be assigned a value (dubbed a Troyer) to signify difficulty level. All of the Troyer levels for each target can be added and averaged to figure out how hard or easy a specific course is. The courses set by our match directors for our club's typical monthly match has a Troyer of around 30. Some examples of a 30 Troyer target are: a 1/2 inch kz at 15 yards, a 1inch kz at 30 yards, a 1.5inch kz at 45 yards. Those sound pretty easy, until you factor in wind, ability to figure out the distance, angle, and the fact that these shots are not taken from a bench. In addition, for an AVERAGE 30 Troyer course, there will be likely be targets that score a 45 Troyer (for example), which would be a 3/8" kz at 18 yards, or a 1 and 1/8" kz at 48 yards. There are also sometimes offhand, kneeling, and/or targets placed in thick brush, or shadows, all of which increases the difficultly level. 

Match directors typically utilize the local flora and topography to create a challenging and interesting match. Here are some of our past target placement situations:

You'll see that some are set high off the ground, on platforms that swing in the breeze, or buried in thick brush. All of that is part of the fun. 

In the past, our matches at the Ben Avery shooting facility took place along a usually dry wash. That area was full of different cactus varieties (mostly Cholla), and desert shrubs. The shooting facility management moved us last winter and we have been shooting on some of the pistol courses. These are barren landscapes that take a lot of the fun away from the interesting target placement. But, the old saying of a bad day fishing beats a day at work.......applies here in that getting to shoot at a less than optimal course beats not getting to shoot at all. 

So, here are some pics of our match today.

This one was taken from the southwest corner, and shows our sight in area. 

This one was taken from the southeast corner, and shows some of the targets.

The pistol course we were on today has berms on three sides and faces north. The wind started out coming from the northeast, but had switched around to mostly being at our backs during the match. The wind was switching directions and hold offs to the right and the left were required, sometimes from one shot to the next. There were only two targets placed at less than 25 yards. Those two both being 1/2 inch kzs at 11 and 13 yards. All the rest were placed further than 25 yards. A windy day, with an average distance quite a ways out, really ups the difficulty level. Mark calculated an average Troyer of 32.65, but that was increased to a 40.5 due to the wind (increased by 1.25 for windy conditions, per Brad's system). In short, a DIFFICULT course. 

It's late and I can hardly keep my eyes open. In a day or two I'll come back and report on how the BSA did. 

To be continued......

 

[fderry]

Thank you for answering my question on the sound level comparison with the air stripper. I was associated with an EPA sound/noise study about 45 years ago, so I have a basic understanding of sound/noise. A lot of folks don't understand the complexity of sound/noise levels and you did a good basic explanation. My accuracy question may not be testable because there probably isn't a significant difference with outside variables (primarily wind) taken into consideration. I hope your readers appreciate how much time your testing, analysis and documentation is costing you. I certainly do!