I know a lot of you already do this, but if you don't, sorting your rimfire ammo as to rim thickness can improve your groups.

I like the Hornady guage the best because it comes with a base that goes on the other side of the caliper. The Sinclair doesn't have that.

By sorting as to rim thicknes, your groups will be more consistant. Also, different rifles will have a particular rim thickness that they shoot the best with. You can save that rim thickness for when you want the best groups and leave the others for practice.

The rims that are either way bigger or smaller I put into a baggie to season a freshly cleaned barrel with.

It doesn't take a lot of time to sort the ammo as to the different thicknesses and will improve your groups. Give it a try.

The Wolf and Federal Auto Match vary from 39.5 to 41.5.

John K