Seems like I have seen posts here from someone with a lathe who does rim work. I have 40 or 50 .44-77 cases made from .348 that need to be thinned to .065 for the C. Sharps style chamber. Thanks if you can help!

Bill,
PM sent.

I usually thin from the rear and deepen the primer pocket if necessary.  It adds an extra step, but is much easier to cut the rim.  Most of the time when only taking a few thousandths off, and the primer pocket is still fine.

If you don't have access to a lathe is there another way of thinning rims? I have to thin the rims on a batch of .35 WCF cases that will not chamber in my Win '95.
Spud

You can always stage the rims down. I once had a hammer swage made for 32-20 to .310 cadet. But a reloading press die would work equally well.

That will work fine. If you can lower and lock your press spindle, you can get it close to the height of a triangular file sitting flat on a steel block. Work slow and it will do a respectable job. The block will give the file much more control.

SBoomer wrote on Jun 10^th, 2024 at 7:23am:

Just to add to this....

Set it up with the case head flat on the block. Then shim the block up the amount you need to remove. Generally 2-3 sheets of paper under will work.

If you use a V block, set it up to support the rim against the pressure of the file. This can produce very good results.

Something else to consider would be if you might use large pistol primers, then take it off the face of the case head to compensate for the difference in cup height.

To further probe the issue of rim thinning, here's another question. Suppose one is working with "modern" .45-70 brass, ie: Starline, W-W, etc., and for one reason or another one had to reduce rim thickness by .015". Would facing off the rear by that amount (essentially removing the headstamp) and then re-cutting the primer pocket to standard depth result in the internal web thickness being reduced unsafely?

Reason I ask is I did that very trick when cobbling together .40-65 cases. I made around 20 of them but stopped before using them when I chose a different solution. (Long story, but that's it in a nutshell.) Have pondered if reducing said web thickness by .015" was risky business or not.