During covid I ordered 1,000 primed cases of what turned out to be Lake city 7.62 x 51 primed cases.  I bought them from Midway, it took about a year to get them.  They looked ok, but they were definitely bullet pulls and still had little pieces of powder stuck inside of them.  I resized them, and loaded 500.  I was loading 175 sierra MK with 44.1 of accurate 2520.  I have now had 3 cases get stuck in chambers, 1 in a LMT ar10, 1 in a Wilson combat ar10, and 1 in my Barrett Mrad.  The rim rips off of the case, and when you try to cycle the gun again it can't grab the case because the rim is ripped off.  Once the case is punched out and hand cleaned it will fit in 2 case checkers I have.  I don't see any physical issues examining and measuring the cases.   The cases are stamped LC  II   then the Nato stamp.  Has anyone had any issue with LC brass?  I've gone through tons of it in 556 and 7.62 and until this batch I've never seen an issue.   Thanks

That powder charge would be OK for a 150-grain.

44.1 grains AA-2520 is seriously over-pressure for a 175 in a 7.62 NATO case.
You're at 103% loading density with a BALL POWDER, and running over 68,000 PSI in a 7.62 NATO case.

SAAMI max for 7.62 NATO is 60,191 PSI.
SAAMI max for .308 Winchester is 62,000 PSI.

Quickload reports the CASE VOLUME for the two is significantly different.
Quickload estimates case-capacity of 7.62 NATO at 52.0 grains water
Quickload estimates case-capacity of .308 Winchester at 56.0 grains.  
I haven't specifically weighed-and-compared because I suck at measuring water in rifle cases. But, internet lore supports Quickload's case-volume numbers in general as it pertains to 308 versus 7.62.

Here's a screenshot of your load in Quickload.
Apologies for the blurry PSI number in the screenshot of the Quickload calculation.
The blur is a flaw in how the screenshots render on my PC.
The blurry number is 68,409 PSI.

It is interesting to note that your same bullet and powder-charge, when run through Quickload using a .308 Winchester model (more case volume) , suggests a safe load.
But clearly your load is showing over-pressure signs with those 7.62 cases.
So there's the lesson.

I have a couple thousand of the same pulldown Lake City cases as you have.
I run TAC in my loads.
TAC and 2520 are so similar as to be functionally identical.
With those pulldown cases, and a 150, I run 44.0 grains TAC.
With those pulldown cases, and a 168, I run 41.1 grains TAC.
My loads are nowhere near SAAMI max pressure. But they are accurate and reliable.
I have a can of safe, but "hot," loads if I need to shoot something that has to be hit harder. Which is pretty much never.

If you want to run those 175's in the pulldown Lake City cases, you can run 41.5 grains 2520 (or TAC).
You'll be around 56,000 PSI, and you'll make about 2390 fps muzzle velocity out of a 16" barrel. You'll pick up about 150 fps if you shoot it in a long(ish) barrel.



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Load data for Lake City 7.62x51mm brass conducted at a government facility Chief Ballistician - Wm. C. Davis Jr.

Can we see the primers?

Way over book max on the Hodgdon website and a few manuals I consulted.