Field Target is an arms race.

[thomasair]

This must be specific to WFTF?

For the American classes of field target (sub 20fpe). If you're 19ish fpe, calling it 50 or 55 won't make you miss. Ie trajectory isn't so loopy that it puts you out of the 1.5" kill zone. Wind reads are a different story.

Can check actual some time, but working from memory I think my 50 and 55 is a 0.2mil holdover difference on that last gun I used in a match. Not positive, but wanna say it was 0.8 mil for 55 and 0.6 mil for 50. At least at my home elevation, going down 5000 feet to that match required me to hold over more. But the difference between 50 and 55 was still only something like 0.2-0.3 mil.

Edit: yeah I checked my Strelok profile for this gun, which as previously mentioned is "close" but not perfect. 0.3 mil difference between 50 and 55 yards.

I imagine it's much more critical with a low BC 8gr and/or a pellet moving 100fps slower.

The 45-55y targets in wftf need exact numbers BECAUSE of the wind. You cannot afford to shrink the width of the kill zone because you are off a little in vertical. If there was no wind to worry about..... +/- 5y would probably be fine if you had a good hold.

Mike

 

[JW.]

If we have good velocity, BC, scope height, and distance measurements, we should not need to “fudge” anything.

Except, a bent up/down barrel will require you to fudge the scope height.

Scope height and target distance measurements should be taken from the scope’s erector tube gimbal. That is especially true for close targets. If you use anything else (muzzle, scope objective, etc) you will be off and that is why you would need to “fudge” at 10yds.

The scope does not “know” where the muzzle is. Sure, drop is calculated from the muzzle, but clicks and reticle holdovers are angles with the vertex being at the scope gimbal. That is the only point where you can expect consistency.

I don't think CG can adjust for canted rails/mounts, if it can i've never found where to do it.

 

[JW.]

At 20 ft-lbs, if your group size at 55 yards is larger than 3/4" your long distance clicks start to matter more in the wind.

Take a dime and put its center towards the top edge of a quarter (head wind), now substitute a penny then nickel (keeping the center in the same location) and you can see how larger groups sizes will create more misses at distance when you can't just aim/hit dead center.

Mike has a great wind charting article that I took a step further and created full charts of wind constants that work with mil/moa reticles and at any rifle power or scope mag level (shoot in a known wind and count the hold off then select the proper chart). I've been using this for a bunch of years now, but more to the point this was a tremendous help at the Worlds and allowed me to basically hit every pure cross wind shot without any real wind practice.

 

[Franklink]

At 20 ft-lbs, if your group size at 55 yards is larger than 3/4" your long distance clicks start to matter more in the wind.

55yd groups larger than 3/4"? Sounds like time to join the arms race and buy something better.

 

[Bramezy]

55yd groups later than 3/4"? Sounds like time to join the arms race and buy something better.

truth! I personally struggle with anything worse than MOA. I feel at MOA accuracy its one less variable I have to worry about.

 

[JW.]

Yep, at 1/2" you can be competitive without fighting the rifle. I was adding on to the need good numbers at distance for WFTF in wind comment. 20 ft-lbs is more forgiving at distance up to a point, which is where the expanded group size starts necessitating other things to be closer to perfect in order to make the hit.

At the Worlds I was a bit astonished to hear "Open shooters never have to hold outside the kill zone." That may be the case for the east coast (it sure was for the Baton Rouge Nats), out west and more so in Nevada holding outside the kz at distance is a common occurrence.

 

[karl_h]

My first job was $6.85, so nearly double what you're talking from the 80s, and Im still blown away by the price of everyday items right now.

I made 2.30 an hour at my first paycheck job, wasn't long before fed min wage went up to 2.65. Thing is before I had my drivers license at 16, a friend and I cleaned properties nearby we could ride our bikes to for a local law firm, about a 10+ mile radius from where we lived. We made killer money, my parents made me get a real job once I got my drivers license, dad said working for a pay check would do me good. I literally cursed him out, only time in my life. Went from making a minimum 750-1k a month averaged out good to bad months, to working 20'sh hours a week for min wage, how stupid is that. With my drivers license we could have taken on triple the work and pulled down at least 3k a month each on average, as much as dad made as an engineer for general electric's electric boat division with compartmentalized security clearances for his design work on nuclear sub controls. Maybe that's why he put his foot down, he would have withdrawn his signature and no drivers license to 18 if I didn't do it. Needed the parents signature on file at the dmv prior to 18 where we lived for a drivers license.

 

[Franklink]

Yep, at 1/2" you can be competitive without fighting the rifle. I was adding on to the need good numbers at distance for WFTF in wind comment. 20 ft-lbs is more forgiving at distance up to a point, which is where the expanded group size starts necessitating other things to be closer to perfect in order to make the hit.

At the Worlds I was a bit astonished to hear "Open shooters never have to hold outside the kill zone." That may be the case for the east coast (it sure was for the Baton Rouge Nats), out west and more so in Nevada holding outside the kz at distance is a common occurrence.

Lol, that's just WFTF shooters trying to belittle 19fpe.

At the matches where I shoot here in Arizona, holding outside the kill zone isn't uncommon. Sometimes off the faceplate even, on the worst of windy days.

 

[thomasair]

Probably every 12 fpe wftf shooter in the USA has shot at 20fpe a lot before going to 12fpe.... while most 20fpe shooters have never tried 12.

There are lots of places in the USA where the Right Edge, Left Edge (RELE) wind hold strategy will get you very far at 20fpe.

Mike

 

[Franklink]

Probably every 12 fpe wftf shooter in the USA has shot at 20fpe a lot before going to 12fpe.... while most 20fpe shooters have never tried 12.

There are lots of places in the USA where the Right Edge, Left Edge (RELE) wind hold strategy will get you very far at 20fpe.

Mike

I shot one of Garrett's monthly matches at Rio Salado with a 6fpe 10meter FWB300s one time. That was a hoot! Really cool to hold off a solid 12 inches on the far targets and watch the pellet hit the paddle and have it not go down. To his targets credit, everything under about 35 yards would go down with a paddle hit, past that, not so much. Of course pellet probably had less than 2-3fpe left by that distance.

I wasn't the low score at that match either. Lol.

Edit: I found it, scored an official 22 (woulda been more like a 32ish had the gun had enough poop to knock over the targets on the paddle hits on the 40+ yard targets). Feb of 2020. High score was a 43 so I'm guessing it was a 48 shot match. Had a couple people scoring less than my 6fpe springer. That was a fun match though, prearranged it with another springer shooter and we both attended with that purpose in mind.

 

[cavedweller]

At 20 ft-lbs, if your group size at 55 yards is larger than 3/4" your long distance clicks start to matter more in the wind.

Take a dime and put its center towards the top edge of a quarter (head wind), now substitute a penny then nickel (keeping the center in the same location) and you can see how larger groups sizes will create more misses at distance when you can't just aim/hit dead center.

Mike has a great wind charting article that I took a step further and created full charts of wind constants that work with mil/moa reticles and at any rifle power or scope mag level (shoot in a known wind and count the hold off then select the proper chart). I've been using this for a bunch of years now, but more to the point this was a tremendous help at the Worlds and allowed me to basically hit every pure cross wind shot without any real wind practice.

Any chance you can link Mike’s article mentioned above?

 

[JW.]

There are lots of places in the USA where the Right Edge, Left Edge (RELE) wind hold strategy will get you very far at 20fpe.

I've been to them back east going to the Nationals!! Except for the second day in Virginia/North Carolina, it was gusting over 30mph easy, you could see leaves blowing horizontally in the scope!

We get a little respite from the winds in Oregon if all goes well, other than that I shoot in more windy places than less windy places.

 

[JW.]

I shot one of Garrett's monthly matches at Rio Salado with a 6fpe 10meter FWB300s one time. That was a hoot! Really cool to hold off a solid 12 inches on the far targets and watch the pellet hit the paddle and have it not go down. To his targets credit, everything under about 35 yards would go down with a paddle hit, past that, not so much. Of course pellet probably had less than 2-3fpe left by that distance.

I wasn't the low score at that match either. Lol.

Edit: I found it, scored an official 22 (woulda been more like a 32ish had the gun had enough poop to knock over the targets on the paddle hits on the 40+ yard targets). Feb of 2020. High score was a 43 so I'm guessing it was a 48 shot match. Had a couple people scoring less than my 6fpe springer. That was a fun match though, prearranged it with another springer shooter and we both attended with that purpose in mind.

When I was messing with detuning from 20 to 12fpe for pistol I over-adjusted the reg and was shooting 10.34's at around 5-6fpe. I could not believe how well it shot out to 35/40 yards at that energy level.

 

[JW.]

Any chance you can link Mike’s article mentioned above?

I found it in a search but its a pdf download so I can't link it, only download it...?

Try this link:
https://www.airgunnation.com › attachments › wind-drift-paper-pdf.314406

 

[Scotchmo]

I don't think CG can adjust for canted rails/mounts, if it can i've never found where to do it.

???

You said “canted rails/mounts”. If you really meant compensation mounts, then you don’t need to adjust for that. Just use the correct scope height at the gimbal.

Cant is dealt with via correct scope installation and a scope mounted bubble level.

 

[JW.]

???

You said “canted rails/mounts”. If you really meant compensation mounts, then you don’t need to adjust for that. Just use the correct scope height at the gimbal.

Cant is dealt with via correct scope installation and a scope mounted bubble level.

20moa rails are often called 'canted' scope rails.

The rail cant/compensation changes the poi similar to raising/lowering the scope height. If BC is known and you put in the turret height and did not compensate in the solver for the angled mount you won't get the proper clicks.

Or if you leave everything the same and swap out a canted/compensation mount with a flat mount your poi will change drastically even though the turret height did not change appreciably. I just had to do this for my 12 ft-lb rig when I went with a 20moa mount over a flat mount to avoid going a whole rotation up at 55 yards, my long distance clicks were completely different.

CG has no solution for this other than to start changing variables until things match the physically collected poi's.

 

[Scotchmo]

…

The rail cant/compensation changes the poi similar to raising/lowering the scope height. If BC is known and you put in the turret height and did not compensate in the solver for the angled mount you won't get the proper clicks.

Or if you leave everything the same and swap out a canted/compensation mount with a flat mount your poi will change drastically even though the turret height did not change appreciably. I just had to do this for my 12 ft-lb rig when I went with a 20moa mount over a flat mount to avoid going a whole rotation up at 55 yards, my long distance clicks were completely different.

CG has no solution for this other than to start changing variables until things match the physically collected poi's.

Say that you replace a 20moa mount with a flat mount, and then add back exactly 20moa via the turret. If all else is the same as before, including the scope height, all of your poi numbers will be the same.

The axis of the erector tube is your line of sight. It does not matter if you add inclination via the turret or a compensating mount. The end result is that the erector tube points the same. The erector tube gimbals at the rear. As long as the scope height at the gimbal is the same as before, it does not matter whether the angle is from the compensating mount, or from the turret clicks. Once it’s zeroed, all of your poi points are the same as before. It’s the exact same triangle.

That said, if your turret adjustments are wonky, it’s possible that the click spacing is not consistent throughout their range of motion. In which case your poi points will not be what the math would predict.

The only way this is related to the original topic, is that better equipment is less likely to have (though not immune from) those kinds of problems.

 

[JW.]

This is getting lost in translation... The point i'm trying to make is if the only thing that changes is the angle of the rail, CG can't account for that drop unless you start messing with BC or something else to counter compensate.

 

[Franklink]

This is getting lost in translation... The point i'm trying to make is if the only thing that changes is the angle of the rail, CG can't account for that drop unless you start messing with BC or something else to counter compensate.

That's simply the ballistic app method.....fiddle with parameters til it's as close as it's gonna get.

 

[Scotchmo]

This is getting lost in translation... The point i'm trying to make is if the only thing that changes is the angle of the rail, CG can't account for that drop unless you start messing with BC or something else to counter compensate.

Everything else being the same, when I add more MOA compensation to the mount, I reduce the clicks by an equal MOA amount, in order to keep the poi the same. It really is as simple as that. Nothing would change in whatever ballistic app I’m using.

However, adding compensation to a scope mount usually results in at least a slightly different scope height. You must remeasure and enter the new correct scope height value in your ballistics app. Measure it near the scope gimbal. If you take the scope height measurement at any other location, you are on your own, because the math will not work in that case.