22 LR Long Range Dispersion, What is the Culprit

[Hi-NV Shooter]

Correct, general question. 300 yd group, I have no idea since I haven't shot 22 LR that far. I was able to shoot out 200 yds just recently and groups averaged 1" with mild conditions. Hopefully when I am able to try 300 yds a good group would be somewhere around 4-5", maybe 6-8", conditions permitting.

Asking too much?

Wow that is fantastic shooting if your average groups were 1" at 200yds.! what were you shooting?
these are my best 5 shot groups at 100yds. and one 10 shots at 100yds. all shot with a re-barreled Anschutz 1411

Lee

 

[vaguru]

Shooting a B 14R steel in a ORYX chassis, Athlon Midas TAC 5-25X56 at 25X. Very good lot of SK LRM that groups consistent .250" or less at 50 yds, SD 5.69. Only 5 shot groups though, no 10 shot groups either distance. I did use rudimentary flags part way out.

Shot off a bench with Rock BR and rear bag, 6 oz TT Diamond, weighs 17 lbs, is my NRL rifle. Trying to test to verify will be good enough for longer range MARS/PRS22.

So now to beg a 300-400 yd range. I'm told past 200 will tell if your setup is good enough for these longer ranges. Unfortunately, longer ranges here are few and far between, and as a guest I won't be able to choose a day for good conditions.

 

[Hi-NV Shooter]

Shooting a B 14R steel in a ORYX chassis, Athlon Midas TAC 5-25X56 at 25X. Very good lot of SK LRM that groups consistent .250" or less at 50 yds, SD 5.69. Only 5 shot groups though, no 10 shot groups either distance. I did use rudimentary flags part way out.

Shot off a bench with Rock BR and rear bag, 6 oz TT Diamond, weighs 17 lbs, is my NRL rifle. Trying to test to verify will be good enough for longer range MARS/PRS22.

So now to beg a 300-400 yd range. I'm told past 200 will tell if your setup is good enough for these longer ranges. Unfortunately, longer ranges here are few and far between, and as a guest I won't be able to choose a day for good conditions.

I hear you, not every range goes past 200yds. I am lucky the same range I shoot ARA goes to 600yds. I only shot 300 yds. a couple of times and I was just fooling around. I have no idea what the groups were as it was steel, and I didn't have a spotting scope.

Lee

 

[Dgd6mm]

Wouldn't that be .5moa at 200 yards? = 1" roughly.

 

[xswanted]

Wouldn't that be .5moa at 200 yards? = 1" roughly.

Yep, roughly 1/2 MOA

Pretty incredible average for sure.

 

[209jones]

Litz had been doing some experimenting with .22lr last year, and blaming the bullets for the most part, supposed to be info on his tests on his paysite.

 

[pmpski_1]

That’s good shooting. A 6” group at 400 yards, consistently performed, is tough.

That was my first thought too.

 

[4xforfun]

There is a non-linear increase in dispersion as distance increases, and this is very obvious in .22LR performance. In other words, rather than a linear increase in group size where group size doubles with distance, especially with .22 rimfire group sizes grow more and more as distance increases.

There are several causes. One is obvious and that is that as .22LR bullets slow down with distance, vertical dispersion increases more and more. To put it another way, it takes the .22LR bullet more than twice as long to get from 100 to 200 than it takes to go from 0 to 100. There's simply more time for bullets to be affected by the inexorable forces of gravity. MV variation serves to make group sizes worse than if rounds had very similar MVs.

The other primary cause is less obvious but no less important. Soft lead projectiles such as .22LR bullets (and airgun pellets) are very difficult to produce with a near perfect center of gravity. Cg imperfection contributes to group dispersion. Some lots -- indeed some rounds within lots -- have more or less perfect centers of gravity than others. The result is that some lots will have greater rates of dispersion due to Cg imperfection than others.

(Individual bores/chambers contribute to the Cg of the bullets that become obturated as they pass through them. This is one reason why some rifles/barrels shoot better at longer distance than others.)

Landy (HuskerP7M8) did a comparison of Lapua testing facility ten shot group results at both 50 and 100 meters and found that on average the dispersion rate between 50 and 100 meters was a factor of about 2.8 times. Some lots are better or worse than others. Same for some rifles/barrels

To put it another way, it takes the .22LR bullet more than twice as long to get from 100 to 200 than it takes to go from 0 to 100. There's simply more time for bullets to be affected by the inexorable forces of gravity.

Gravity would affect ALL of the bullets equally....

 

[4xforfun]

As the distance increases the dispersion deviates from a cone and becomes a vortex as the velocity falls off rapidly, it's no longer linear.

View attachment 1574840

This is true, as long as the forces that are moving the bullet remain, and remain constant.

 

[padom]

Ive done some extensive 22lr testing across 39+ and counting barrels and 26,000rd of match 22lr Ammo on a RimX the past few years.

50yd with lot tested ammo my good barrels hold 10x5 50rd AGG in the high 0.1's and 100yd 30rd 6x5 AGG in the low 0.5's

200yd 0.5moa is very very tough and mostly comes down to wind and lot tested ammo. In all my testing, ammo that shoots lights out at 50yd is NOT the ammo that shoots lights out at distance. Sometimes it does really good at 50yd and 100yd. But MOST of the ammo that shoots really good at 50yd is the same ammo that shoots tight @ 100, 200 and 300...


My best, most consistent ammo shooting 200-500yd 22lr was FGMM Ultramatch and RWS R50.


This is some 200yd group shooting I did with a little wind condition out of a new Green Mountain 4140 with non-lot tested RWS Special Match..

And this 416SS Green Mountain RimX barrel has shot the smallest single 50yd and 100yd 5 shot groups Ive ever shot out of a repeater to date with a bipod and rear bag...

50yd 5 shots CenterX - 0.01"

100yd 5 shots - Federal Gold Medal UltraMatch - 0.187"

 

[dgeesaman]

Ive done some extensive 22lr testing across 39+ and counting barrels and 26,000rd of match 22lr Ammo on a RimX the past few years.

39 barrels and 26,000 rounds means you haven't shot a broken-in barrel yet. Are those numbers accurate?

 

[padom]

39 barrels and 26,000 rounds means you haven't shot a broken-in barrel yet. Are those numbers accurate?

LMAO. We let the targets decide if a barrel is broken in yet. Cut rifled Kriegers and Bartleins have shot lights out 0.1 AGG's @ 50 from the start while button barrels have taken 500-1000rd to tighten up and break in.

We have some barrels with 5000rd+ on them and we have some barrels only tested for 500-1000rd.

Your post is laughable at best.

 

[dgeesaman]

LMAO. We let the targets decide if a barrel is broken in yet. Cut rifled Kriegers and Bartleins have shot lights out 0.1 AGG's @ 50 from the start while button barrels have taken 500-1000rd to tighten up and break in.

We have some barrels with 5000rd+ on them and we have some barrels only tested for 500-1000rd.

Your post is laughable at best.

26000/39 = 667 round per barrel. That question asked itself. It's a number that only makes sense to me in short range benchrest.

Why so many barrels? Are you scrapping most of them?

 

[scclimber]

Regardless of the ‘broken In’ part, it is a fair question. Are there just that many barrels that don’t meet expectations and get pull off relatively quickly ?

 

[padom]

Because we were sent one of the first 5 RimX's from Zermatt before its public release along with 2 barrels each from Lilja, Shilen, Green Mountain, Benchmark, Krieger, and Bartlein to chamber with our custom reamer for testing and review.

We have since continued testing of additional barrels from these manufacturers as well as additional barrel makers like Lothar Walther, ACE and Mullerworks.

We have also tested LOTS of different lots of CenterX, Midas+, Ultramatch, R50, RWS Special Match, SK+, SK RM, SK PM and SK PMS

Most barrels were sent on down the line to shooters after testing and data recorded but I still have a good pile of them on the shelf.

 

[padom]

Regardless of the ‘broken In’ part, it is a fair question. Are there just that many barrels that don’t meet expectations and get pull off relatively quickly ?

No. We have been testing for concistent accuracy @ 50 and 100yd from each of these barrels.

We have also been logging ammo pickiness (does one or two types or lots shoot stellar, or does lots of different types and lots shoot stellar), and how many rounds does it take for each barrel to shoot tight. From the start, after a few hundred rounds, 500rd, 1000rd.

 

[dgeesaman]

That makes more sense.

The other possibility i had wondered is if this was misunderstood to be about 22BR or something. I don’t know anyone who could actually consume so many rimfire barrels in so few rounds.

 

[grauhanen]

Gravity would affect ALL of the bullets equally....

It should go without saying that gravity affects all the bullets equally. It can't be otherwise.

But perhaps you missed the relevant point, which is as distance increases the bullets take longer to get to targets farther away. During this longer time, vertical dispersion due to gravity increases. This is one reason why group dispersion increases with distance.

 

[vaguru]

Ok folks here goes. I was able to beg some time at a range yesterday that goes to 400 yds. Weather was 90* F and wind was supposed to be no more than 5 mph, but they lied, was variable to about 10 mph. Radar map showed no rain for the day, more about that later.

Set up targets at 100, 200, 300 and 400 yds, with large white paper backer at 300 and 400 yds. 10 shots 100 yds to warm up barrel and check for conditions, then out to 200 yds. Groups at 200 not as good as last weeks, but still managed 2 5 shot groups that averaged 1 3/4", horizontal, wind and mirage going right left, but held elevation of 1/2".

So out to 300 yds I went. Wind now changing from right left to head wind to tail wind, 5-10 mph. I didn't expect much but waited for a similar condition and let it fly. As I was trying to determine 300 yd zero as my primary objective, I was more concerned with not shooting in head or tail winds. I was holding off 1 mil consistently for conditions, and determined my turret setting. Tried no groups due to the wind, but each string held elevation to 3-3 1/2" and windage would vary from 5-7". The conditions were worse than 200 yds, so now moving out to 400 had me wonder if it was worth trying.

At 400 yds, mirage was left right to start and then changed to right left consistently, running flat like a river. The wind settled down some and gained some cloud cover, so no bright sunlight. Again trying to determine sight settings, so not overly concerned with groups. Tried my first setting and was low about 12", so marked and tried again adding .4 mils. I was holding 1.8 mils windage, and first group that was not enough. Vertical was decent at 7 1/2" but horizontal went 10 1/2". Second try was to high by about 6 " and again held elevation of 7 1/2" and the horizontal was about 11". I marked them and went for 3rd try, down .2 mils.

It was very overcast now, and the wind had let up to about 3 mph, so I only held off .6 mils. I fired three shots, verified impact through spotting scope before all the heavens opened up. It poured for over half hour so hard you could not see the 100 yd target! I still had 7 rounds left for that test and unloaded and waited. I watched my target and backer at 400 get soaked and hoped it would stay put. When the rain let up it was near dead calm, nothing moving and could see the target was still there. I let the last 7 shots go quick as I could operate the bolt, and held dead center.

Those 7 shots were a group, 7 1/2" to be exact, 7 1/2" elevation and 5" horizontal, just 2" right of POA. Turret setting still needed up .1 mil for POI, but I was pleased with result. I pulled target and backer to let dry out in bed of my truck, and it started to rain again. No more shooting as it poured again for another 1/2 hour, and so hard couldn't load up the truck. And after a 10 minute break, that let me load the truck, poured again for the ride half way home.

So now I have determined that my rifle, ammo combo will do better than hoped, still looking for that unicorn lot however.

I don't think that 1.79 MOA at 400 yds is terrible. It appears that this combo will produce half minute +/- inside 200 yds, and 1 3/4 to 2 MOA out to 400 yds. I hope to get to try again under more consistent (near ideal) conditions if I'm able to be invited to that range again, but for now I'm satisfied.

 

[CharlieNC]

200yd 0.5moa is very very tough and mostly comes down to wind and lot tested ammo. In all my testing, ammo that shoots lights out at 50yd is NOT the ammo that shoots lights out at distance. Sometimes it does really good at 50yd and 100yd. But MOST of the ammo that shoots really good at 50yd is the same ammo that shoots tight @ 100, 200 and 300...

What do you attribute this to? It is generally discussed as a difference in velocity and/or tuner setting affecting a positive compensation change as a function of distance.