rim thickness

jmcp

I have an anschutz 1417zg and use it mostly for hunting,but i like to put up a target and do a bit of grouping. lately i have been using match ammo etc to get better groups, and I can see how all this works,except rim thickness. how does rim thickness make a difference and how much variation in rim thickness is needed to make that difference.

Cass

jmcp wrote: »

how does rim thickness make a difference and how much variation in rim thickness is needed to make that difference.

Rim thickness on a rimfire cartridge can effect headspacing, and differences in headspace causes inconsistancies in accuracy/groups. So if you want to be utterly anal about it you can;

• Sort ammo by brand
• Further sort by batch
• Further sort by weight
• Further sort by OAL
• Further sort by rim thickness
• Further sort by concentricity

Do all that then the only reason for not gettig a perfect score is you.:D

Sparks

To be honest, with the best will in the world, there aren't more than a dozen or two smallbore shooters in Ireland for whom that kind of thing is worth worrying about. Yeah, you might gain a point or two or even three from doing it, in a 600-point match... but you'll get far more gain for putting the same amount of effort into just plain practicing. And if you're using a 14xx series anschutz, odds are you wouldn't even gain the point or two anyway.

Just buy a box of all the kinds of match-grade ammo you can find locally, shoot 10-shot groups with all of them on a calm day off a rest, and choose the kind that gives you the smallest and roundest groups and buy a brick of that, and then completely forget about the ammunition and just practice.

Cass

In my benchrest days i used to read all kinds of stuff. From rim thickness to concentricity to batching, etc. Some was easy to do and made perfect sense. Others were hard to do, and some down right impossible.

The issue of rim thickness, as said above, is for the "ultra" shooter, and the gain is not reflective in the effort. I found myself checking every round, every batch until i found a problem sometimes where there may not have been one.

I eventually scrapped everything, and went back to basics. Finding a round, and sticking with it. Doing my own "batch testing" then buying in bulk. It is very easy to get lost in the hows, what ifs, and maybes, etc. If down the road you feel you would like to try then i would suggest buying a scale, and try batching, within your batch of ammo. Weighing each round, and boxing them according to the weights. Be warned i tried this, and it got very boring, very fast.