What does it take? (group size)

J

John Whidden

Guest
What is the accuracy standard for the BR game these days? I'm just getting my feet wet with 50M prone shooting and need to know where my gear stands.

For a 50 yard group, what can you shoot for group size? Let's say a 5 or 10 shot group. What does it take to win?
 
You're gonna want a gun that in a decent condition will shoot 5 shot .25" groups. Many will better that by 1/3-1/2.
 
So a gun that would agg .250 for 5 5 shot groups is fully capable of winning many benchrest matches, correct? Or do you mean that to win many benchrest matches you have to have that gun that will shoot .125-.170?
 
JOHN, ARA is worst edge scoring,I don`t think a rifle that only shot .250 would win unless you were the only shooter there.your .125 to .190 would get you there in ARA and PSL targets. Get you a rifle and join us at the Rocky River Barn the first Weekend in Dec. 100 plus shooters for the ARA Indoor Nationals
 
That is correct. Here's a tidbit for you. Now there's not too much real group shooting that takes place but in All ARG matches last year, you know how many aggregates there were registered under .25"? Four, all year. So if you take any of these targets, score them, and then figure an approximate group size, those numbers I gave you will hold up pretty good.
 
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10-4, that meshes pretty well with other info I've gotten.

Some accomplished prone shooters have suggested that excellent accuracy would be about 11mm outside to outside at 50M, so about .216 for 10 shots at 54 yards.

Though some of this shooting is in machine rests, most is outside off of bags. Given that our equipment is not optimized at all for bench shooting I'd think we have a reasonable comparison still.

Obviously a lot of things have to be right to obtain accuracy at the top levels (.125-.170 as you guys say), but on the subject of ammo how many different lots might be tested to obtain this level of accuracy? If a shooter buys 5 different lots of Xact or Tenex is that likely enough? Would you expect to test 10, 20, or more lots?
 
Whoa

John Whidden said:
For a 50 yard group, what can you shoot for group size? Let's say a 5 or 10 shot group.
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Follow up… Some accomplished prone shooters have suggested that excellent accuracy would be about 11mm outside to outside at 50M, so about .216 for 10 shots at 54 yards.
Click to expand...

I'm thinking outside to outside would be on the order of 20.25mm (0.797")

Prone%20-%20Edge%20to%20Edge.png


Open to correction(s)… of course.

dwd

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dwd- Yes, your illustration would show two shots that would each be scored a 10 and I agree with your math.

Don't forget that for a shooter to shoot a perfect score with the level of accuracy you illustrate, every shot would have to be fired perfectly and he couldn't ever miss the wind. This is a hard trick given that we're holding the rifles and aiming with iron sights rather than scopes.

Better accuracy just gives us more room for error, and we have plenty of sources of error! If my stuff shoots tighter than the next guy, I can break a shot that's not quite as good or miss a wind change and my shot *might* still be a 10.

There is no difference between better accuracy and shooting at a bigger target!
 
To shoot a 2500 in ARA, you must have a 25 shot group that is smaller than .276" CTC, and the group must be centered on the target. I have been using a new computer program that will scan a 25 shot target and then tell you what the 25 shot group size is as well as what the 5 shot group size is of each row. So, after shooting 1 target you have one 25 shot group size and five 5-Shot group sizes. It is extremely accurate. I have been using it for a few months now, and I have probably tested 30+ rifles with it. A very good rifle will shoot under .300 for 25 shots. The best rifle I have tested so far shot a .283" 25 shot group, I have only had 4 rifles shoot under .300". The best rifle did have a couple of 5 shot groups that were very small, but it is extremely difficult to do that 5 times in a row. I have the data in front of me from 1 rifle that shot a 25 shot group of .288".
1st Row was a 5-shot group of .288"
2nd was .160"
3rd was .129"
4th was .244"
5th was .160"
You have to remember that it only takes 1 bad shot to ruin a group. On this rifle, luckily the 2nd-5th groups were inside the first group. I have seen 2 different 5 shot groups be very small but when you overlap them, the cumulative 10 shot group is horrible. If 1 group has a point of impact to the left of the dot and the 2nd group has a point of impact to the right of the dot, you end up with a large 10-shot group.
 
Curiosity and the cat (not Shrödinger's)

dankillough said:
To shoot a 2500 in ARA, you must have a 25 shot group that is smaller than .276" CTC, and the group must be centered on the target.

I have been using a new computer program that will scan a 25 shot target and then tell you what the 25 shot group size is as well as what the 5 shot group size is of each row.
Click to expand...

Off topic, It'd be interesting to know if that target software is available for a NON-microshaft O/S. And how big does the scanner need to be ?

Also, likely off topic, but I don't see how the accuracy demand for the ARA target relates to that of the OPs ISSF 50M / 50Y prone accuracy question ? Just seems the requirement of one venue doesn't apply to the other, the ARA one is much more demanding (of equipment) than that of the ISSF 50M/Y target.

ARA%20vs.%2050M%3AY.png


Not forgetting, one is "handheld" the other a COMPLETELY unrestricted benchrest event, albeit outdoors, one assumes since the wind can "blow down a target" along w/ worst edge protocol for scoring.

dwd
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dankillough said:
To shoot a 2500 in ARA, you must have a 25 shot group that is smaller than .276" CTC, and the group must be centered on the target. I have been using a new computer program that will scan a 25 shot target and then tell you what the 25 shot group size is as well as what the 5 shot group size is of each row. So, after shooting 1 target you have one 25 shot group size and five 5-Shot group sizes. It is extremely accurate. I have been using it for a few months now, and I have probably tested 30+ rifles with it. A very good rifle will shoot under .300 for 25 shots. The best rifle I have tested so far shot a .283" 25 shot group, I have only had 4 rifles shoot under .300". The best rifle did have a couple of 5 shot groups that were very small, but it is extremely difficult to do that 5 times in a row. I have the data in front of me from 1 rifle that shot a 25 shot group of .288".
1st Row was a 5-shot group of .288"
2nd was .160"
3rd was .129"
4th was .244"
5th was .160"
You have to remember that it only takes 1 bad shot to ruin a group. On this rifle, luckily the 2nd-5th groups were inside the first group. I have seen 2 different 5 shot groups be very small but when you overlap them, the cumulative 10 shot group is horrible. If 1 group has a point of impact to the left of the dot and the 2nd group has a point of impact to the right of the dot, you end up with a large 10-shot group.
Click to expand...

Dan,

My best 25-shot group thus far is a 0.243” with the 5-shot subsets averaging 0.167”, but the next 25 shots ballooned to .311” and 0.226” respectively.

Here’s a few numbers to think about pertaining to the data you posted on that specific rifle and the groups it shot.

Those 5 groups have a calculated Standard Deviation of 0.067” and that means if you were to continue shooting 5-shot groups with that rifle....2 out of every 3 groups you fire will range in size from 0.129” to 0.263” and the remaining group or 1 out of every 3 will range from 0.063” to as large as 0.330”.

The average size of those 5 groups equals 0.196” and it takes a rifle capable of 5-shot groups averaging 0.185” to shoot 25-shot groups of 0.276” (2500 ARA).

For a rifle to shoot two consecutive 2500’s or a 50-shot group of 0.276”, it would have to average 0.167” for 5-shot groups and 0.249” for 25-shot groups.

Here’s the kicker though.....5x5-shot groups are only the barest indicator of a rifle’s accuracy and a poor one to boot, as is a single 25-shot group, and as is the calculations made above based on only 5 groups. Shooters trying to tune or lot test ammo simply must employ more sophisticated measures to get reliable results, but in many cases it becomes a matter of practicality or most often the unwillingness to spend the effort.

Landy

PS deadwooddick, do you honestly believe that prone shooters don’t strive for the ultimate in accuracy just as BR shooters do? This isn’t off topic! This is exactly what the OP wants to know. I think?
 
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John:

To be truley competitive in .22 rf BR, you will need a rifle that will shoot .200 of an inch groups at 50 yards.. Three, five, ten or twenty groups doesn't matter, but it will have to group .200 or better at 50 yards. And then, sometimes, that is not good enough..

JHMO

DAve
 
Yes, this kind of analysis is exactly what I'm interested in. I can score my own target and know what kind of group I can shoot. I need to know the standard that my equipment should live up to without my introducing shooter error into it.

The 50M matches we shoot are 60 shots at a time. I guess really I'm interested to know what kind of 60 shot group I'm looking for. Thanks for the statistics to do the math- looks like I'll sit down with Excel tonight for a few minutes.

For a rifle to shoot these top notch groups, how many different lots of ammo would you expect to shoot to find find the right stuff? 5, 20, 50?
 
Deadwooddick,

I am not sure if the software would be available for anything other than Microsoft. The software will print its on targets on 8.5x11 paper, so you can use an average size scanner. I only put the ARA reference in the post to give readers a reference point. Most shooters do not shoot 25 shot groups and therefore do not know what is a good group size.
 
John,

Good points made, and agree with Dave. When I sent a record target to Bill Myers who built the rifle, he measured that 25 shot group and believe it was a .178. I also have 2 more record targets one with 33 shots the other 35 shots, Thats counting the 8 sighters that were shot on a ARA target. Those targets were measured, the 33 shots measured .158 the other .166, those three record targets were shot in a dead calm condition. That rifle is a freak of nature and it's a pleasure knowing that a rifle is capable of shooting like that.

I believe the more you know your rifle and what experience's one has with ammo, the quicker it is to select what will work best in ones rifle. Test lots are harder to come by these days, the ammo is gone very quickly by the time you do any testing with different test lots. I have to refer back to what machine and speed per say my rifle likes the best but again it's not a guarantee but limits the amount i would have to test otherwise.
 
Jeezum, crow…

HuskerP7M8 said:
PS deadwooddick, do you honestly believe that prone shooters don’t strive for the ultimate in accuracy just as BR shooters do?
Click to expand...

I didn't say that, but YES both "should" want to achieve the most accuracy from their equipment. Just intrigued as to how ARA "needs" can be applied to those of ISSF/NRA Prone competition.

Richard
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Gonna worry DWD to death...

From shooting long range prone, I'd estimate that my LR guns probably shoot groups about 10% bigger than a really good bench gun at 1000 yards. Personally I speculate that the 10% difference goes to that last bit of loading room time and probably more to the fact that prone guns are hard to shoot off a bench!

I'm thinking if my rimfire can be about 10% behind you guys on group size, then I should get off the internet and go practice prone with it! Thanks DWD and all who have contributed to this thread to help me understand what it takes and where the standard is.

John Whidden
 
I got a stupid question. I always measure my groups sentre to centre. Are the group sizes quoted here CTC?

I have also heard people quoting minute groups (on other fora) of around .1" with sporting rifles. For the life of me, I cannot get anything like that with my target rifle.

Am I hopeless or are others blowing smoke?
 
I got a stupid question. I always measure my groups sentre to centre. Are the group sizes quoted here CTC?

Yes

I have also heard people quoting minute groups (on other fora) of around .1" with sporting rifles. For the life of me, I cannot get anything like that with my target rifle.

If you mean 0.1” groups at 50 yds or meters with a rimfire....anyone can do it. It’s just a matter of how many hundreds or thousands of groups you fire until this highly improbable event occurs. I’ve done it more times than I can count but I’ve never come close to that figure for a series of groups or an average and if anyone says they have....I’m gunna require proof of it. Everybody loves to shoot these very rare itty-bitty groups and brag about them, but they have absolutely nothing to do with the true accuracy of a firearm and I would hope that most realize that.

Am I hopeless or are others blowing smoke?

If you’re asking a question and desiring an answer....you’re never hopeless. LOL
Blowing smoke? There’s so much of that occurring on internet forums that the Fire Department quit dispatching trucks to put the fires out a long time ago. LOL

Landy
 
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