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<MADDOG>
09-18-2020, 14:46
Sorry if this was addressed, I seen nothing in the search.

All right gentlemen, I have challenge which you may know how to fix, and I have not run into it before with any other brass. I have some current reloads with 7.62 x 51 LC, with some I started to process, and have run into an issue.

I used small base dies (both RCBS and Lee), but approximately 8% of the resized brass does not fit the Lyman case gauge (including after trimming to length). About the same % of previously loaded rounds were also confirmed to close hard/if it all on a bolt gun after failing the gauge.

I have read elsewhere that it is best to first run the brass through a .30-06 die, then back through the .308. Is this true? Or should I accept that M240's eat brass and just gauge each one prior to priming?

Madusa
09-18-2020, 19:47
In my experience case gauges only are good for length, gerth is another issue.my reamers are sloppy in a case gauge.

beast556
09-18-2020, 22:21
I had the same issue with 7.62 brass. I switched to winchester brass and haven't had any issues. I only load match 308 so I figured it wasn't worth my time to mess with the 7.62 brass.

Hoser
09-19-2020, 08:03
I added more lube and it actually improved things. Seemed to resize easier and move the brass more efficiently.

Then I started roll sizing all my 223 & 308 brass before I process it. Problem solved.

<MADDOG>
09-20-2020, 06:11
I had the same issue with 7.62 brass. I switched to winchester brass and haven't had any issues. I only load match 308 so I figured it wasn't worth my time to mess with the 7.62 brass.

Agree, I have not had this problem on any other commercial brass at all. This is specific to LC 7.62.

Hoser, that looks like a nice gadget, and if I still needed the volume that I did when I was in CO, I may have bit!

Oscar77
09-21-2020, 12:19
OP:
My suggestions are:
-lube those cases very generously.
-I'd think that if the SB dies (unless somehow not set up properly) would resize more than the "30-06" approach, so cull them and move on.
(I suppose if you have the 30-06 die, it cant hurt..... but I wouldn't go out a buy the thing. Your SB dies should've done it).

<MADDOG>
09-22-2020, 16:14
OP:
My suggestions are:
-lube those cases very generously.
-I'd think that if the SB dies (unless somehow not set up properly) would resize more than the "30-06" approach, so cull them and move on.
(I suppose if you have the 30-06 die, it cant hurt..... but I wouldn't go out a buy the thing. Your SB dies should've done it).

Yea, that is where I am at now...

I played with all three of my dies the other night, & adjusted up/down all to check my sanity. There was absolutely no difference made.

I "smoked" a couple of cases as well. It appears from the markings left by the gauge, there is a "bump" at the shoulder, the head/body is too far expanded, or in a couple of circumstances, both.

Educated guess: my particular lot of .mil brass has M240 or worse mixed in, and the LC thickness/composition is just to thick to overcome the fire forming that occurred in whatever chamber it was fired in.

Overall - I will chalk it up to learning lesson, and if I buy another bulk order, I'll expect 20% cull rate on the brass as worse case.

C Ward
09-22-2020, 19:42
Unless your brass has the LR headstamp for M118LR all modern 7.62 will be exclusively fired from MGs .