Small-base dies

[fstdraw]

Recently I sized a bunch of 7.62x39 brass that wouldn't fit into the case gauge. I purchased a SB die from RCBS and it seems to make no difference in getting these cases to fit into the case gauge. What's the deal?

Thanks

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[Certaindeaf]

Recently I sized a bunch of 7.62x39 brass that wouldn't fit into the case gauge. I purchased a SB die from RCBS and it seems to make no difference in getting these cases to fit into the case gauge. What's the deal?

Thanks

What press are you using?
Do you know about "cam over"?

 

[P7M13]

1) Where's it get stuck? Please picture a case in the gauge that didn't fit.
2) Measure a few of the cases that don't fit to see what are the root cause(s).
Here's a cartridge dimension drawing from Wikipedia. The lines won't show up if you're viewing in dark mode.

 

[fstdraw]

Yes, cam over on these. It's just the last 1/16" that has to be forced to go into the case gauge. RCBS single stage.

 

[Mikej]

Maybe this is stoopid?....Do they fit in the gun?

 

[po18guy]

Why do you need a case gauge? Most 7.62 X 39 rifles have pretty tolerant chambers. As long as the case is sized and not over max length, all should be OK. And, there are several types of gauges. Which do you have?

EDIT: The reason for small base dies is if an auto-loading rifle has chambering or extraction problems. AKs and SKS rifles will feed and extract almost anything. A bolt gun with a tight chamber might need small base dies, but that would be a rare exception.

 

[fstdraw]

Thanks

 

[po18guy]

Honest questions from seasoned geezers.

 

[fstdraw]

Yes, I agree, geezers.

I think its foolish to go through all the hassle of reloading and NOT take measurements every so often to ensure exact tolerance and shoot-ability in ALL firearms designed for that particular cartridge. That's why I ask questions (even from reloaders not as experienced as I) to get faster, more exacting, safer or just better ways of doing things. Really, if you don't have a case gauge for your most frequntly loaded calibers, get one. Just the same as you should have Lee FCD for your crimping needs. I load for 5 different 7.62x39 guns. You're correct that AK's and SKS's will shoot ANYTHING with "7.62x39" on the casehead, including reloads. However, the AR platform with this cartridge is a bit fussier. So I'm careful and check most reloads of this caliber. I load brass and steel cases, so sizing can be an issue. I want these rounds to be accurate, safe, reliable in all guns.

I thought SB dies would get me better sizing for the crap brass that's floating around out there, it does not. Half the reloaders on here have suggested SB dies in the past, my experience now is, don't bother. Throw away the stubborn cases, no matter how pretty, and move on.

Thanks for the geezerly advice. It's always welcome.

 

[SHPD_Retired]

I have actually had a bad case gauge. Just an idea

 

[Koda]

I think its foolish to go through all the hassle of reloading and NOT take measurements every so often to ensure exact tolerance and shoot-ability in ALL firearms designed for that particular cartridge.

I would think its virtually impossible to take measurements that would fit -all- chambers out there for any given caliber.
If your goal is to reload to [safely] fire in -all- rifles then all you need to do is "cam over" any full length sizing die. Im my limited experience, FL sizing dies form well below sammi specs specifically to fit all -sammi- chambers.

 

[arrowshooter]

Don't know if you have looked this up, but:

 

[arrowshooter]

Does a new round fit in the gauge?

 

[fstdraw]

Yes on cam over.
Gauge is fine.
I just got some bum bubbleguming brass that I tossed out today.

THE END!