I have done some testing of rimfire ammo sorted by weight and rim thickness. I sorted ammo to .1 grains by weight and .001 in rim thickness. I did this for 5000 rounds of Wolf Match target, and hundres of rounds of other ammo, some cheap bulk ammo and other inexpensive box ammo. I also sorted several hundered rounds of the other higher end ammo, like RWS 50 and 100, as well as SK's match ammo.
In summary, the cheap ammo, bulk, or boxed, can not be made to shoot better by sorting. It's just cheap ammo that will never shoot benchest accuracy. The Wolf Match Target did see significant improvement in accuracy by weight sorting, but sorting by rim thickness produced no improvement with this ammo. And, sorting by rim thickness showed no improvement in any other ammo either. The very expensive target ammo, like Lapua and Eley, does not need any sorting as it's dead on in both areas when it comes from the factory.
So, I've taken Wolf Match Target that costs $3 a box and made it shoot as well as ammo costing $12 per box. I did no comparing of the other ammo, like RWS 100, that I did sort and shoot, but only shot it sorted, and have no comparison to how it shot without sorting. By the way, that RWS 100 sorted shoots extremely well, just like Wolf Match Target sorted. It depends on what rifle shoots each ammo best.
I have about 20 high grade 22 Rifles, and most shoot the Wolf best of all ammo tested. I have much of the high end ammo that I test, along with Wolf, with each rifle to see what ammo it likes best, and Wolf does well in most.
When I sorted Wolf, and shot it in a Suhl 150 (very accurate rifle that shoots Wolf best), I found that a difference in ammo weight of 1.2 grains produced groups that were separated by 1/2" at 50 yards for 5 shot groups. No difference in poi could be determined by shooting ammo with the widest variance in rim thicknesses; it all shot in the same hole.
So, I've given up on sorting by rim thickness, and do sort only Wolf by weight. All of the testing was in support on my 22 Rimfire benchrest shooting. If a particular rifle I'm shoot likes the $12 a box lapua ammo best, I do no sorting of it before shooting a match.
Edited by Martyn4802 (04/04/07 06:52 AM)
Retired US Army
NRA Benefactor Member
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