Its unlike you to make such an ambiguous comment, thats why I’ve asked for clarification.
Sort Ammo by Rim Thickness, Reduce Flyers
- Thread starter Zee705
- Start date
Its unlike you to make such an ambiguous comment, thats why I’ve asked for clarification.
Obviously you want as low as possible which is why you lot test.
My current batch of Eley match that I compete with I get an ES of 26 and an SD of 6.5.
With those numbers I’ve been able to shoot 5 - 5 shot groups in the mid .1’s.
The ES and SD of CCI SV and SK S+ that the op found is the same as I have seen in my CCISV and SK S+. Not very good. Out of my T1X, 10 rnd groups average just under 2” at 89M. CCISV is slightly better than the S+. I don’t sort by any criteria.
Those are some small groups!
I know the idea is to have the lowest ES and SD, I was just clarifying his comment. Sounded like he was saying the numbers were high for those brands.
So far it would seem that the sorted rounds show a lower ES and SD. It took me about 40mins to sort the 2 bricks of ammo, so for now the juice seems worth the squeeze with these brands. For my purposes I'd like to reduce the ES as much as possible to reduce the vertical spread on targets. If my research is correct a 10fps difference between shots @ 200yards could mean an inch of vertical spread, at 300 that spread would be even more significant. I'll complete the same test with match ammo at a later date, since supply is tight I'm not very interested in burning a couple hundred rounds over the chrono. At minimum this looks like a method of improving the ammunition I use for practice.
Has anyone else tested this out?
With Eley match ammo, separating 0.037+ and 0.037- makes sense when you realize there is no >0.036 nor <0.038".
Following up on some of the other measurements from others where the range is 0.0410 - 0.0445, then it makes sense.
However, the dilemma occurs when a rifle likes 0.0410 to 0.0415 and there are only 2 - 5% in the whole box.
Now the search goes towards a brand of ammo where the rim thickness is within the preference for your rifle.
A rifle was chambered with a Eley Match Chamber and specified 0.0415 head space. It would not chamber CenterX.
The man building this rifle was a follower of Calfee (spellcheck not working).
My Remington was also chambered by DRS but I did not specify headspace and I have not even tried CenterX.
I’m glad you brought this up, this might be a more easily tested concept.
Sorry to be a dummy, but does any of the conversation in this thread (which is extremely enlightening for me) also carry over to center fire casings? I understand the idea of consistency in the round sizing vs. best matching to headspace, and total round weight, but are there other measurements one could take?
It has been noticed elsewhere that if there's a premium product rated eg +/- 1% of spec and a bulk product rated +/- 5% then if you go through and test a pile of the bulk ones there's an interesting gap in the middle because the vendor already did that to select the premium ones!
In that case it might make sense to separate the overspec from underspec because there are two distinct bands there, but if you need quality then just buy quality in the first place.
In that case it might make sense to separate the overspec from underspec because there are two distinct bands there, but if you need quality then just buy quality in the first place.
Your figure is correct. A 10fps difference between rounds means about .25" at 100 yards, 1" at 200 and about 2.3" at 300. (See the chart below.)
The greatest difficulty is finding a certain lot that will give a low ES in your particular rifle (it can vary from one rifle to the next). There's no guarantee that the name or the price on the box translates to good numbers.
All .22LR ammo will have ES figures that will vary by lot, including CCI SV and SK Standard Plus. Some will be better than others. A good lot of SK + for example can have an ES under 40 fps but a higher number should be expected. CCI SV numbers usually aren't as good as those of SK +.
Much more to measure with Centerfire, and with handloading, you can actually do something about it! Neck thickness (turn your necks for consistent diameter), case run-out, primer seating depth, case weight, case volume, flash-hole uniformity, neck-size when reloading vs full length resizing so that the case is custom fit to your chamber, bullet jump to rifling, ideal powder charge, ideal powder burn rate. Might be a few others but those are the main ones off the top of my head.
Tonight the shooting was with three brands that had been shot last week.
Remington Target, CCI SV and CCI Green Tag. None are what I would consider Match grade out of the box.
While the samples were divided in to three groups best described as low (thin), medium and high thick).
Each brand showed a preference to one of the groups.
Use a larger sample that will have at least 50 rounds in one of the groups.
Measure the median group to within1/1000 high and low: ie. 0.040 to 0.042 or 0.040 to 0.041. Your choice as you will want a statistical amount outside of the captured group open both sides (higher and lower).
You don't need to order the Bald Eagle from the USA. I have been able to accomplish almost as accurate results with a 243 Win Case that was trimmed flat and the inside of the neck chamfered lightly. A little slower but good enough for the girls I shoot with!
Every rifle is different and his procedure will probably not produce match ammo. As with a tuner which is designed to make match ammo better. There are no guarantees.
When I was finished tonight I fired five rounds of Eley Match and five of Lapua Biathlon and concluded I should stick with match grade ammo.
Remington Target, CCI SV and CCI Green Tag. None are what I would consider Match grade out of the box.
While the samples were divided in to three groups best described as low (thin), medium and high thick).
Each brand showed a preference to one of the groups.
Use a larger sample that will have at least 50 rounds in one of the groups.
Measure the median group to within1/1000 high and low: ie. 0.040 to 0.042 or 0.040 to 0.041. Your choice as you will want a statistical amount outside of the captured group open both sides (higher and lower).
You don't need to order the Bald Eagle from the USA. I have been able to accomplish almost as accurate results with a 243 Win Case that was trimmed flat and the inside of the neck chamfered lightly. A little slower but good enough for the girls I shoot with!
Every rifle is different and his procedure will probably not produce match ammo. As with a tuner which is designed to make match ammo better. There are no guarantees.
When I was finished tonight I fired five rounds of Eley Match and five of Lapua Biathlon and concluded I should stick with match grade ammo.
I finally got around to putting the results together so here they are in all their anecdotal non-scientific glory.
I think the better test would to record velocity like others have done. Your mileage will absolutely vary when it comes to groups.
Things I will do to pickup a few extra points at an ORPS match.
1. Practice
2. Pray
3. Bribe the spotter
4. Sort for rim size
Maybe I'll try sorting by rim size and weight as my next adventure in quasi-science.
I think the better test would to record velocity like others have done. Your mileage will absolutely vary when it comes to groups.
Things I will do to pickup a few extra points at an ORPS match.
1. Practice
2. Pray
3. Bribe the spotter
4. Sort for rim size
Maybe I'll try sorting by rim size and weight as my next adventure in quasi-science.
Thought I would revive this discussion, seems we’re not the only ones on this topic:
I would think 5 groups is not enough to prove or disprove the concept, and it would have been valuable to see sorted shot, then weight sorted shot then the weight/rim sorted shot.
So far I’ve noticed that my CZ457 MTR shows lower ES and SD with rounds with .042” rimthickness vs other rim thickness and unsorted ammunition all from the same lot. I have not applied the testing to groups…yet.
I would think 5 groups is not enough to prove or disprove the concept, and it would have been valuable to see sorted shot, then weight sorted shot then the weight/rim sorted shot.
So far I’ve noticed that my CZ457 MTR shows lower ES and SD with rounds with .042” rimthickness vs other rim thickness and unsorted ammunition all from the same lot. I have not applied the testing to groups…yet.
