Tuning Maverick Power Wheel Works In Reverse?

[Member 32425]

Just another fyi, but I would order that spacer from FX, if you order the spring from them. I don't think it is a "normal" sized spacer you could just grab at the hardware store. It probably wouldn't be a bad idea to have one on hand, just in case I am using the spacer on mine, and I was using it prior to putting the Huma spring in it too. Granted, I'm pushing my gun harder than many do, but I've always used that spacer on pretty much every tune. Good luck, I hope the new spring gets ya sorted out!

I just now looked at the schematic for the maverick and there is no spring spacer shown at all, so I don't know what part number to order.

I was thinking about one possible benefit that spring spacers might offer even if extra preload is not needed. When a coil spring is compressed or uncompressed it will "twist" a bit as it does so. Maybe a spacer or two will let the spring "twist" as it wants to (happier spring?). I don't know. Mechanics and physics is not my strong suite. I'm just thinking outloud and I'm wrong about stuff like that more often than I'm right.

 

[Member 32425]

A lot of misinformation has been put out about the Maverick, Starting with the poor owners manual. Then came the vague, incomplete and even wrong information on fx you tube. Not until Matt came out with HIS IN DEPTH regulator adjustment did I fully understand the adjustment procedure.

Now I've been enlightened by you wonderful guys about the hammer screw! I followed the ( apparently wrong) 6mm instructions. I've have similar problem where 6&7 settings give me no more or less fps. The conundrum is that I have a very good shooting gun on 1-5. 6/2.2. On 2 I get 4/1.8. However I can not achieve slug speeds. I did previously. Until I 6mm'd the hammer. I didn't catch on till these posts. When you have a spot on shooter ( 25g) it's hard to understand your set up wrong.

I have 25 compact, believe it or not, I 8" gong it @ 155 yds. But not enough fps for 34g or to tighten the spread. Like to put a longer barrel on but you can't get them.

Thanks every body. Now I have something to go on!

Keyman, welcome to the club where finding information that relates to exactly the issue(s) you need to address is always an adventure. When I start looking through posts here on AGN intending to find an exact answer to an exact problem I have, well... it's like when I go to the hardware store to just get one thing. Sometimes I end up coming home with nothing. Sometimes I come home with lots of stuff, but not the thing I went to the hardware store for. And sometimes I get exactly what I was looking for and consider myself lucky that day.

I took a quick look at places that might have the maverick .25 barrel kit -- places I thought you might not have looked and I found just pre-orders like you did. A longer barrel will definitly give your slugs the long runway they need to take off.

grungy

 

[Keyman62421]

Just got back from range. Turned hammer screw in 2 rounds. Got on chronograph. Had to up regs 10 bar each. Now at 110 hammer 4. 25g @920. 34g @850.

Hammer slap all but gone. Sighted in @ 25yds. 34g bull is 2 clicks up from 25g zero. Athlon gen2 mil. Both moa @ 100. Rocking an 8" , 1/2" thick "gong" @125.

Absolutely satisfied..all by reading this post. INVALUABLE! keep reading and learning.

 

[Rallyshark]

Just another fyi, but I would order that spacer from FX, if you order the spring from them. I don't think it is a "normal" sized spacer you could just grab at the hardware store. It probably wouldn't be a bad idea to have one on hand, just in case I am using the spacer on mine, and I was using it prior to putting the Huma spring in it too. Granted, I'm pushing my gun harder than many do, but I've always used that spacer on pretty much every tune. Good luck, I hope the new spring gets ya sorted out!

I just now looked at the schematic for the maverick and there is no spring spacer shown at all, so I don't know what part number to order.

I was thinking about one possible benefit that spring spacers might offer even if extra preload is not needed. When a coil spring is compressed or uncompressed it will "twist" a bit as it does so. Maybe a spacer or two will let the spring "twist" as it wants to (happier spring?). I don't know. Mechanics and physics is not my strong suite. I'm just thinking outloud and I'm wrong about stuff like that more often than I'm right.

It seems you are correct. I'm not seeing that spacer shown in the diagram either. I'm sure an email or call to FX asking for a Maverick hammer weight spacer will get you one though. I can't comment on the spacer performing other functions though, since I haven't tested with and without... At least you've found part of the issue with the hammer spring though

Just got back from range. Turned hammer screw in 2 rounds. Got on chronograph. Had to up regs 10 bar each. Now at 110 hammer 4. 25g @920. 34g @850.

Hammer slap all but gone. Sighted in @ 25yds. 34g bull is 2 clicks up from 25g zero. Athlon gen2 mil. Both moa @ 100. Rocking an 8" , 1/2" thick "gong" @125.

Absolutely satisfied..all by reading this post. INVALUABLE! keep reading and learning.

It's always a good day when you get your gun doing what you want! Hopefully, the barrel kits will start appearing again.

 

[Rallyshark]

Hey Grungy, it looks like your shorter hammer spring may not have been a "mistake" on FX's part? I say that, because my second Maverick finally showed up this week, and it also has a 52mm hammer spring in it?! Either FX has made a parts change, or they are making multiple mistakes. My gun came as a Sniper .30, and I couldn't get it to make any more power past about 130-ish bar. At that point I was out of adjustment on the hammer spring screw. I figured "Oh, they just put the wrong hammer weight in there", so I pulled it and weighed it. It clocked in at 13.2 grams, then I remembered this thread and decided to measure the spring. Sure enough, it was 52mm. Also, this one didn't have a spacer in it either.

Fortunately, I still had the spring that came with my first Maverick that measured 56mm, since I had upgraded it to the Huma Impact spring. I went ahead and put one of my own hammer weights I had made during some of my tinkering. The new hammer weight that I installed was 15 grams, I figured the extra gram or two wouldn't hurt, since I don't have a spacer with this gun. Now the gun is doing just fine with a 150-ish bar second reg setting, and I still have 2 or 3 mm of adjustment left in my hammer spring It looks like you should be good to go when you get yourself a full length hammer spring and maybe a spacer(if needed). I just thought I'd update you guys, so you can just go ahead and measure that hammer spring if you can't seem to make the power you should from your new Maverick.

 

[Member 32425]

Hey Grungy, it looks like your shorter hammer spring may not have been a "mistake" on FX's part? I say that, because my second Maverick finally showed up this week, and it also has a 52mm hammer spring in it?! Either FX has made a parts change, or they are making multiple mistakes. My gun came as a Sniper .30, and I couldn't get it to make any more power past about 130-ish bar. At that point I was out of adjustment on the hammer spring screw. I figured "Oh, they just put the wrong hammer weight in there", so I pulled it and weighed it. It clocked in at 13.2 grams, then I remembered this thread and decided to measure the spring. Sure enough, it was 52mm. Also, this one didn't have a spacer in it either.

Fortunately, I still had the spring that came with my first Maverick that measured 56mm, since I had upgraded it to the Huma Impact spring. I went ahead and put one of my own hammer weights I had made during some of my tinkering. The new hammer weight that I installed was 15 grams, I figured the extra gram or two wouldn't hurt, since I don't have a spacer with this gun. Now the gun is doing just fine with a 150-ish bar second reg setting, and I still have 2 or 3 mm of adjustment left in my hammer spring It looks like you should be good to go when you get yourself a full length hammer spring and maybe a spacer(if needed). I just thought I'd update you guys, so you can just go ahead and measure that hammer spring if you can't seem to make the power you should from your new Maverick.

Rallyshark, I ordered the Huma Air FX Impact Tuning Hammer Spring from trenier outdoors. Jeff at trenier measured it for me. He said "The length is 2.262” and the wire diameter is .055” and 15 coils total". So the length of the huma spring is 57.4548mm vs the 52mm spring that came with my maverick sniper .30. And the wire diameter is exactly the same as the wire diameter of my "short" 52mm spring. My 52mm spring has about 18 coils vs 15 coils for the huma. The huma spring will arrive in a couple of days. When I got my maverick, one of the first things I did was take out the hammer weight and check the weight of it on my powder scale. My hammer weight is also 13.2 grams. Using nsa 49.5g slugs and going through air pressure settings from 120 bar to 155 bar (bumping up about 3 bar at a time) and varying the hammer preload screw for each air pressure from all the way in to out until it wouldn't cock (1/4 turn at a time and hammer wheel always on 7), the best velocity I got was 915fps which is about 92fpe and that was at 130 bar (130 bar sound familiar?). It was really consistent -- two full mags and max spread of only about 10fps. But at every air pressure the best velocity I got was always with the hammer spring preload totally maxed out. I should point out that I am using the Huma Air FX Airguns Wildcat MKIII / Maverick .30 Pin Probe from trenier outdoors.

So the bottom line, it appears, is that neither one of us can get more power from our newer maverick sniper .30 at air pressures above 130 bar with the short 52mm spring fx put in them. This is good info for me and probably will be for others as well. When I get the new spring and have new chrony data with the same nsa 49.5 slugs I will post them here. Thanks Rallyshark.

 

[Rallyshark]

You'll be on a different level with that Huma spring in there! That's what I have in my other Maverick(along with other stuff), and it is a beast! I was using the NSA 43.8 slugs in my new Maverick(because I don't shoot them much). I managed to get them up to 1000 fps(97fpe) with the factory parts in the new one, but that was the limit. As a contrast, my "old" Maverick can do well over 130 fpe. The new Maverick will be relegated to the .177 and .22 calibers, and I'll let the old Maverick handle the heavy hitting duties.

Currently, the new Maverick is tuned to shoot the NSA 31.2 grain slugs around 960-970 fps with the reg around 150 bar. It should be money with that tune and the Superior Heavy liner. That's what I usually tuned my other one to with the same barrel setup. I look forward to hearing the difference in your gun after you get that new spring!

 

[Larry1956]

I have a 30 Maverick shooting 44.8grn JSBs at 881fps and 77fpe with 1st reg 175 and 2nd reg at 155 on Power Wheel 6 with 500mm barrel. I bought the gun in this configuration. Hammer spring is 56mm long and HSA is at 3.56mm. At this setting I have extreme spread of 9 and std dev of 3 with 5 shots. Since this rifle is very accurate and consistent groupings at longer distances, I zeroed it at 60 yards. Question is can I do better on my tune. The reason I ask is when I step up to Power Wheel 7 I go down in power to 75fpe at 871fps but my extreme spread and std dev goto 2 and 1 out of 5 shots. Keeping the HSA the same, Is this the most efficient tune?

 

[Rallyshark]

I have a 30 Maverick shooting 44.8grn JSBs at 881fps and 77fpe with 1st reg 175 and 2nd reg at 155 on Power Wheel 6 with 500mm barrel. I bought the gun in this configuration. Hammer spring is 56mm long and HSA is at 3.56mm. At this setting I have extreme spread of 9 and std dev of 3 with 5 shots. Since this rifle is very accurate and consistent groupings at longer distances, I zeroed it at 60 yards. Question is can I do better on my tune. The reason I ask is when I step up to Power Wheel 7 I go down in power to 75fpe at 871fps but my extreme spread and std dev goto 2 and 1 out of 5 shots. Keeping the HSA the same, Is this the most efficient tune?

I would just shoot it on power level 6. You're wasting air on PW7, and that will be a less efficient tune for sure. If you wanted to set it perfectly, so PW7 is where it does it's max speed, you'll probably need to turn the HSA in about 1/2 turn. Currently, you're just over driving the valve on the highest setting. Don't get lost trying to make your ES slightly less, because you'll never see the difference on target and you'll use more air is many cases. You don't want a "chrony queen", you want a gun that shoots well and does it efficiently

 

[Member 32425]

Rallyshark (and all), I got the huma fx impact tuning hammer spring. The length, etc., is as Jeff from Trenier Outdoors measured. I only shot 11 rounds of nsa 61.5 slugs to get a feel for tuning my maverick sniper .30 for highest power (I really want a frick'n beast like your first maverick). With the whimpy 52mm spring that came with my gun I could only get 92fpe regardless of slug weight, air pressure, and hammer preload. With the huma spring, the best power I got from a quicky run of 11 rounds of nsa 61.5 with air pressures from 138 to 150 bar and varying hammer preload (large jumps with both air pressure and hammer preload of course) was 107 fpe. Better by far, but not super great. But it was very enlightening because now I see why anyone could think that the power wheel works in reverse. My best fpe (107fpe) was at 145 bar with the power wheel set at 6 and hammer screw turned all the way IN. I was no where near maxing out my hammer spring preload. Higher preload just lost fpe and higher air pressure required more preload but still failed to get to 107fpe.

I remembered that you initially made a 15 gram hammer weight (2 grams heavier than the fx heavy 13 gram hammer weight) and that you also use hammer spring spacers (effectively adding to the mass of the hammer weight). In my opinion, more hammer weight mass is exactly what my maverick wants now to become the beast that I want it to be. So the huma spring is throwing the hammer weight (and hammer) faster, but without more hammer weight mass (momentum), the hammer is just bouncing off of the valve when I increase the air pressure above 145 bar. I am trying to find some hammer spring spacers to effectively increase the hammer weight mass.

I hope this is in some way helpful to others.

grungy 

 

[Rallyshark]

If you want more power, go ahead and put that reg up to 155-160 bar. That 13g hammer weight should have no problem cracking that valve. The adjustments with the screw can make a big difference, so I think you probably just went from not enough to too much during your quick testing. Sure a heavier hammer weight would make it easier, but I don't think you really need it just yet. I don't think you'll need it, until you change out the FX regs for the extra high pressure Huma regs. I've noticed the gun is much easier to tune with the Huma regs too, because they refill much faster. The FX regs will make you scratch your head, because they'll fill to about 90% quick but the last bit takes a long time and will throw you off with the tuning. At least, that what they did with me. The first thing I did with Maverick number 2 after it's first range day, was put the Huma regs in it as well. Now, I don't have to worry about riding the edge of where I want the reg and what is too high for the FX regs, and they(Huma) refill much faster.

I'll warn you about tuning for high power, especially in .30. That is when the little block on the cocking rod likes to move, since that larger probe size allows the air pressure to push pretty hard against the probe. That will make the linkage move a little, if those two grub screws aren't locked down well. Either way, that 13g hammer weight should be good up to about 170 bar(at least). You should have what you need to get to around 120 fpe now. That is, assuming you have the pin probe and it's adjusted to seat as deep as possible while still allowing the magazine to clear. The Huma pin probe works very well too, but you may have to shorten the tip just a little to clear the magazine. I can't remember, but it you still have the factory probe, that will probably hold you to around 115 fpe give or take. You can also go after the factory probe with a dremel to make it flow better. I hope that helps  

 

[Member 32425]

If you want more power, go ahead and put that reg up to 155-160 bar. That 13g hammer weight should have no problem cracking that valve. The adjustments with the screw can make a big difference, so I think you probably just went from not enough to too much during your quick testing. Sure a heavier hammer weight would make it easier, but I don't think you really need it just yet. I don't think you'll need it, until you change out the FX regs for the extra high pressure Huma regs. I've noticed the gun is much easier to tune with the Huma regs too, because they refill much faster. The FX regs will make you scratch your head, because they'll fill to about 90% quick but the last bit takes a long time and will throw you off with the tuning. At least, that what they did with me. The first thing I did with Maverick number 2 after it's first range day, was put the Huma regs in it as well. Now, I don't have to worry about riding the edge of where I want the reg and what is too high for the FX regs, and they(Huma) refill much faster.

I'll warn you about tuning for high power, especially in .30. That is when the little block on the cocking rod likes to move, since that larger probe size allows the air pressure to push pretty hard against the probe. That will make the linkage move a little, if those two grub screws aren't locked down well. Either way, that 13g hammer weight should be good up to about 170 bar(at least). You should have what you need to get to around 120 fpe now. That is, assuming you have the pin probe and it's adjusted to seat as deep as possible while still allowing the magazine to clear. The Huma pin probe works very well too, but you may have to shorten the tip just a little to clear the magazine. I can't remember, but it you still have the factory probe, that will probably hold you to around 115 fpe give or take. You can also go after the factory probe with a dremel to make it flow better. I hope that helps

Rallyshark, once again you have provided super-valuable information that I could not have gotten on my own. So here are a couple of things in no particular order as to where I'm at.

I never mentioned this before and maybe it's not relavent to this post, but here it is. The brass breech section of my barrel has the stock transfer port, so it's just a big round hole. I de-burred the edges of it to keep slugs from jamming, but I did not enlarge the hole at all because I didn't want slugs to try to fall into the hole. That totally solved the jamming problems I was having. I did that by using bamboo shishcabob (spelling?) skewers. I put them into a variable speed hand drill (not high-speed dremel) and just worked the edges of the hole with the bamboo through the transfer port -- not through the hole that the slugs enter the breech from (I think it's important to know that). The bamboo is so soft that it was a no-risk operation and worked great.

I have the Huma .30 pin probe. I still need to check to see if the fat part of the probe is partially blocking the transfer port -- I think it probably is. So I will check that and move it back as needed for best air flow. I know what you mean about the cocking rod block with the two set screws. I have mine firmly tightened and I use locktite blue (removable). My pin probe is protruding enough when cocked to keep the magazine from being inserted/removed. But I don't mind that since I can simply pull the cocking lever back with my pinky while inserting the mag with my thumb or removing the mag with my thumb and index finger. It's not a big deal for me because I'm never in a situation where I need to quickly swap mags.

I have two hammer spring spacers on the way from fxusa. I will put one spacer on. Later, if I think an additional 2nd spacer would be of any benefit, then I'll try that.

I know what you mean about the FX regulators taking so long to fill. When I'm writing down my chrony numbers, I always write down the exact pressure to within about 0.5 bar before taking the shot because it could vary depending on how long it's been since the last shot. Thank you for letting me know that the huma regs do not suffer so much from that issue and that they can handle higher pressure. I would not have known that without your feedback.

I'll be happy to get the 116fpe that fx advertises and more power is a bonus. I guess I over-stated a bit when I said I wanted my maverick to be the beast that your first one is. I still haven't had this gun completely disassembled -- scary.

So now I feel quite confident that I can get to that 116+fpe without any major modifications. It just comes down to running a lot of slugs through the gun making small changes, keeping a log of all my chrony numbers and settings at the time the shots were taken, etc., oh -- and think!

Thanks Rallyshark.

grungy

 

[18.13]

My .30 Maverick 600mm came with the 11g weight with a washer for 11.5g. I haven't cranked it up to see what it will do but it shoots the 50gr JSBs at 880 with the preload barely turned up, just idling reg pressure is 114 with the Wika gauge 

 

[Rallyshark]

Grungy, I'm happy to help when I can! That factory barrel port will make plenty of power, and there's no real need to upgrade it to the huma. You can slightly chamfer the outside edges of the hole with a dremel or file to help with air flow from the transfer if ya want, but not totally necessary for the power you're looking for. As long as your probe removal screw is in the center of the access hole(under the cheek rest), there's no need to adjust the position of the probe with the set screws on the cocking rod/side lever block. I doubt your probe is blocking the port at all. A common problem with the .30 Mavericks was actually that the probe wasn't seating far enough, so you should be just fine there. However, you can take a bit off the tip of the Huma probe to make loading the magazine a little easier. I actually took a bit off the tip of the one I have, with no ill affects. I just used the grinder while rotating the probe in my fingers. It doesn't take much. You can always take a little off, but you can put it back, so a little at a time is the way to go if you do shorten the pin. Again, not really necessary in your case I don't think.

The Huma Extra High Pressure regs are great, because they are good from 135 bar to 210 bar, which means they'll be right in their sweet spot for a high power tune. I will warn you, they won't degas like the FX regs, so you'll have to shoot them down as opposed to taking a shot and them degassing themselves like the FX regs. That's not an issue for me, since I rarely need to lower them. Once I get my tune, I don't really mess with the regs much at all. In your case, I'd put reg one at 170-180 bar and reg 2 at 160. The rest will be in the hammer adjustments. You have everything in place to make the power you want for sure. The other thing I'll say is make sure you dump those FX gauges, if you don't have the WIKA, Huma, Sekhmet, etc. on there. Those factory little gauges were way off on my first gun. The newer Maverick had the WIKA gauges, and they were pretty spot on, although I did replace my rear gauge with a larger Huma gauge that was easier to read smaller adjustments. I put the Sekhmet on the rear gauge location on Maverick number 1, which is the one I have tuned for full beast mode.

If you plan on shooting heavier slugs(which you'll need to get in the 115+ fpe range), go ahead and get you some of the NSA 54.5, 61.5, or 65.5. They do great in the superior heavy liner! You'll have that gun humming in no time I think.

 

[Member 32425]

Rallyshark, here's an update on my maverick .30 sniper and a couple of questions for you. I have the stock .30 transfer port (just a round hole) and I have not beveled the outside of it. I do have good wika 28mm 0-250 bar gauges on front and rear (I wouldn't want anything else -- love 'em -- easy to read to within 1 bar for a nearsighted guy like me). I have the huma .30 pin probe and I checked to make sure that the fat part of the probe was not blocking the transfer port -- it's not blocking and the pin has the slugs seated well in front of the transfer port also. The pin is sticking out enough when cocked to block the magazine from being inserted/removed without holding the cocking lever back while doing so, but I don't mind that. If I shorten the pin I won't be seating the slugs as far into the barrel. I have the 1st reg set to 180 bar and the 2nd reg at 160 bar now. I have the huma power tune hammer spring. I also put one fx impact spacer between the hammer weight head and the hammer spring. The spacer is about 1.42mm (maybe 1.46 -- don't remember exactly) thick, so just having that on there is adding almost 3 power wheel clicks of compression to the spring. 1 power wheel click is exactly 0.5mm of compression and thankfully it so happens that exactly 1 full turn of the hammer preload adjustment screw results in exactly 0.5mm change in preload also. That's nice because it makes it easy to put the spring compression to a known setting by putting the power wheel where I want and turning the screw in all the way and then backing it out less than 1 full turn. This gives me an easy way to make note of preload settings. Like 3.25 is power wheel on 3 and 1/4 turn out on the screw. 5.75 would be power wheel on 5 and screw turned out 3/4. 8.5 would be power wheel on 7 and screw out 1.5 turns. Part of the reason I mention this is because I want to be able to shoot different weights of slugs by only changing the hammer preload setting and leaving the air pressure alone on a high pressure setting. Maybe it's not possible to get the best tune for all but one weight of slug without changing air pressure.

I chronographed nsa 49.5 and 54.5 slugs with 2nd reg at 160 bar and walked up the hammer preload 1/4 turn at a time to give the following results. My chrony measures in meters per second.

NSA 49.5

3.0=269mps

3.25=276mps

3.5=277mps

3.75=284mps

4.0=283mps

4.25=287mps

4.5=287mps

4.75=293mps

5.0=293mps

5.25=295mps

5.5=297mps

5.75=298mps

6.0=298mps

6.25=298mps

6.5=299mps=981fps=105fpe

6.75=299mps

7.0=297mps

7.25=290mps

7.5=287mps

7.75=287mps

NSA 54.5

3.0=260mps

3.25=264mps

3.5=267mps

3.75=271mps

4.0=275mps

4.25=275mps

4.5=279mps

4.75=279mps

5.0=281mps

5.25=284mps

5.5=287mps

5.75=287mps

6.0=289mps=948fps=108fpe

6.25=289mps

6.5=289mps

6.75=284mps

7.0=283mps

7.25=282mps

7.5=281mps

7.75=278mps

Sorry for all the blank lines -- don't know how to prevent it. I didn't have time to chrony the 61.5 grain slugs. My buddy was coming over to pick up the maverick to take to his cabin for the week and it was dark and about to rain. I actually set the hammer preload to a bit less than max power before giving him the gun to hopefully be more efficient with air and give up a bit of power for better accuracy (slug maybe won't get kicked in the ass so hard on it's way out of the muzzle and be more stable). I don't know if my max power is on par with what I should expect from these weights of slugs at 160 bar. Let me know if anything seems off to you.

So I have a couple of questions. Do you think my pin probe is pushing the slugs TOO far into the barrel? Would that make any difference with power? With accuracy?

What is the max air pressure the standard fx regulators on this gun can handle without risk of damage? FX doesn't tell us guys much of anything.

When you mention the heavy liner, are you talking about the 1 to 18 twist rate barrel liner? My maverick came with a 1 to 22 twist rate.

If I bevel (chamfer) the outside of the transfer port, I was thinking I'd use a stone grinding bit on a hand held power drill. I'm thinking maybe I use a 45 degree angle a small ways in and then a 60 degree angle a little further in and smooth with ultra fine sand paper. The idea would be to give it more of a trumpet bell shape -- like the carb intake of a fully blown funny car. Sounds like a pain in the butt to even find grinding bits shaped to specific angles now that I think of it.

Thanks guys for putting up with my rambling. It's football day and I'm out of beer. Happy shooting.

grungy

 

[Rallyshark]

That's a lot to take in there! I can tell you that you need to turn the hammer adjustment screw in a bit to get it where it is making the max power with the power wheel on 7 as opposed to 5.5-6. I would take bit off that pin probe, just to make inserting the magazine easier. I don't think it will affect your speed at all, nor your accuracy. As long as the slug is making it just past the barrel port, then you're good to go. The max FX says the regs are good for is 170 bar. I know of many people that have run that first reg higher with no issues. I just got the Huma extra high pressure regs, because I don't want to be worrying about regs failing or creeping.

Right now, the thing that is getting me is that the power hasn't really increased much from when you had the second reg at 145-150 bar. You should have enough hammer spring/weight to make more power than you are. The fact that the speed is decreasing at a certain point on your hammer spring adjustments tells me you have enough hammer to over drive the valve, so I don't think you need more hammer. All of that in mind, I think air flow is limiting you. It could be an o-ring leaking on the barrel during the shot cycle. I would go ahead and chamfer the outside edge of that barrel port. You don't have to make it like a work of art, so do get to crazy with the ultra fine sandpaper or anything like that. A small file will do just fine. The stone on a drill may not work that well, because the brass will clog of up that stone. What works best is a dremel(or other rotary tool) with a small carbide cutter. It makes it real easy to take a little off at a time with very little pressure. There are many ways to do that really, just do it the way that works best for you.

Another note about the slugs. Don't worry about pushing them too fast, because they like speed! Given you are using the standard superior(22" twist) and not the superior heavy(18" twist), I don't know that it's going to like the heavier slugs. It will probably do much better with the 54.5 and under(especially the under). Let me know if you need more clarification  

 

[Member 32425]

Thanks Rallyshark. When my buddy gets back from the cabin I'll check for leaks around the breech area. Hopefully I've just got a bad o-ring. That does remind me of something really stupid I did the first week I had the gun (this is embarrassing). The first time I had to bleed the air from the gun I dry-fired it one time AFTER the gun was completely out of air. I had the whimpy 52mm spring in it and the power wheel was only on 3 or 4, but I knew that was one of the dumbest things I could have done. I kind of dismissed it as not a problem when my buddy and I were happily taking out ground squirrels at 100 yards with lighter weight slugs at lower air pressures. But now I'm wondering what that dry-fire without air could have done. I'm new to pcp rifles so I don't know exactly how the hammer and valve assembly works.

I'll go ahead and order the 1:18 twist rate superior stx barrel liner, because I'll mostly be shooting slugs from 49.5 and up. Will slugs lighter than 49.5 do OK with the 1:18 twist rate?

On a side note, I've seen videos where guys unscrew the barrel shroud and the 10mm lock nut that holds the liner in the barrel housing without putting the barrel in a vise -- they just left the barrel on the gun while doing that. I don't have a vise so it's tempting to swap liners with the barrel still in the gun. What do you think? Bad idea?

grungy

 

[Rallyshark]

I doubt the dry fire hurt anything, as long as you didn't do it a bunch of times with it out of air. I don't know if you have a slight o-ring leak or not, that was just a guess. Your power isn't super low, just a little bit lower than I think it should be able to do. Working on that barrel port could solve that as well. The superior heavy liner does not like the really light stuff at all in my testing. The lightest I could get mine to do well with was the 49.5, but that was very fussy about speed. The 54.5 shoot wonderful out of the heavy liner though! They are lasers in the 940-960 fps range with that liner, as are the 61.5 and 65.5. I think tuning for the 54.5 would be the perfect tune to shoot for. If you want to shoot lower power, switch over to pellets. I believe I remember people saying the pellets still do great in the heavy liner. I never tested that theory myself though.

You can change the liner with the barrel assembly still in the gun. Just do you you mentioned, and you'll be fine. The only time you may need to pull the whole thing is if the wrong end starts to unscrew, because it is tighter than the barrel nut you're trying to unscrew.

 

[Member 32425]

Thanks Rallyshark. Great info! The dry-fire without air was a one-time goof -- won't happen again. When I got the new hammer spring and spacer I replaced the breech o-ring, but I did not use grease on it -- I just put it in dry. I'll grease it. It's also possible that I didn't clean out the breech o-ring groove as completely as I thought after de-burring the inside edge of my transfer port (might still have some bamboo dust in there). So I'll bevel the outside of the transfer port and make sure all is cleaned well and put new o-ring in with grease this time (just enough to make it shiny and slippery -- no globs of course). I have a good feeling about putting a bevel on the outside of the transfer port.

The 1:18 barrel and shooting 54.5 and heavier nsa slugs sounds right on. I've got plenty of hammer now with the huma power tune spring and a spacer. The spring preload will never be maxed out to get best velocity at even really high air pressures. Where did you get your Huma Extra High Pressure regs? I didn't see anything specific to the maverick and there are 1st, 2nd, and maybe 3rd generation regs -- kind of confusing. I just want to make sure I get the correct ones for the maverick .30 when I can afford them.

Thanks for the info about removing the shroud and lock nut. That helps more than you know. I was really nervous about it until now.

grungy

 

[Member 32425]

Hi Rallyshark (and all again). It's been a while since I followed up with this. Thank you Rallyshark. Everything you have told me regarding my FX Maverick 30 cal Sniper is right on! With the 2nd reg at 160 bar (it actually settled down to between 155-160) and the 1st reg at 180 bar (it probably has settled down to high 170's) and with the huma pin probe, huma power tune spring, and one hammer spacer, I am now getting at least the max power that FX advertised. I have lots of hammer preload left that could be used at higher reg pressures, but I won't push the FX regs any harder than I already am and I don't need to. The muzzle velocities and power I am getting depends on which chrony I believe in most. I have a cheap Chinese chrony that I really love that only measures in meters per second and never misses a shot -- I trust this thing to get relative muzzle velocities. I also have an FX Radar chrony that I don't trust any farther than I can pee with my enlarged prostate (I nicknamed it the Voodoo chrony -- now printed on the side of it in big easy-to-read letters). The FX chrony is better than it was before I modified the battery source to 4 NIMH cells instead of only 3 (FX does not know a volt from an amp -- they should stay out of the electronics business). So the FX chrony says I'm getting an average of 992 FPS with NSA 49.5 gr slugs. The cheap Chinese chrony says I'm getting a bit over 980 FPS. One very interesting observation is that the power of my FX Maverick Sniper 30 cal has increased just by putting a lot of slugs through it without changing reg or spring preload or slugs used (been sticking with NSA 49.5 gr) and without cleaning the barrel (it always looks OK when shining a flashlight through it, so no need to clean). My mountain man buddy who actually shoots this gun (I'm more of the designated mechanic) has reported to me that it's shooting high -- flatter trajectory than what I told him it would have when I handed it to him to take to his cabin. We talked about this "increased power" mystery at length (over a lot of beers). He figured maybe the very pure lead slugs are kind of sealing the barrel to the exact shape that the slugs need. I said, "I guess so, don't clean the barrel".

grungy

EDIT: The muzzle velocities I reported above for NSA 49.5 gr slugs are not the max I can get (I can get more). The velocities I reported are with the hammer preload backed off from the top of the power curve to make sure that I am not over-driving the valve or wasting air.