8x50R Aus Forming Issues

[junkbug]

Does unfiered 7.62x54r cartridges fit in the chamber ok?

[Moleman-]

I was hoping the annealing would do the trick for you. You don't suppose they sent a 8x56R or a 8x50 Lebel die mismarked as a 8x50R do you? Your chamber cast looks like a 8x50R which has more of a shoulder than the 8x56R. I'd be tempted to do a casting of the die to see what the ID of it measures.

[TheAbe]

I haven’t had the ability to test any, but FL-sized 7.62x54R does not fit...hits the shoulder.

[TheAbe]

I was hoping the annealing would do the trick for you. You don't suppose they sent a 8x56R or a 8x50 Lebel die mismarked as a 8x50R do you? Your chamber cast looks like a 8x50R which has more of a shoulder than the 8x56R. I'd be tempted to do a casting of the die to see what the ID of it measures.

I don’t believe the manufacturer makes 8x50R-Lebel dies, nor 8x56R dies. My chamber cast does look like an 8x50R vs an 8x56R (and 8x56R won’t chamber anyway...got some “free” with my en-bloc clips).
One other possibility is that at one point, this rifle may have had its barrel removed and re-attached...what would be the result if it were tightened one revolution too much? Would that effectively shorten the chamber 1 thread width? Is that even a possibility? I’ve never removed or attached a barrel before and am uncertain what all goes into the process of head spacing for a rimmed-cartridge rifle barrel... any input from those whom have?

[36g]

A rimmed cartridge should headspace on the rim, not the shoulder. The chamber can actually be somewhat sloppy from that standpoint as the shoulder just needs to allow the cartridge to chamber. Critical headspace dimension is the rim thickness in relation to the bolt face.

[TheAbe]

On suggestion of a member I tried taking a formed case, removing the decapping pin, and pressing it back on the die on top of the shell holder. This helped, but a dummy round still won’t quite fully chamber. The case revealed scratches mid-shoulder now. I’m going to try new PPU brass, since that’s what everyone else seems to be having success with, and if that doesn’t work the die is going to be trimmed.

Has anyone else had issues with a new 8x50R die they purchased in the pst few weeks?

[TheAbe]

Does unfiered 7.62x54r cartridges fit in the chamber ok?

Took the dies, casting, and formed cases to my lgs for advice. After a bit of discussion and measuring he gave me a few loose unfired 7.62x54R Winchester brass he had laying around to experiment with. I’m hopeful as the shoulders of these unfired cases seems set back about as much as they need to be. Will Test as soon as I’m able.

[TheAbe]

Ok, new angle: this is a photo of the chamber as best I could do with my phone. Is that a bit of broken extractor wedged in there? The shiny bit sticking around the rim and back into the cutout for the extractor (upper right in photo depending on orientation.). It doesn’t interfere with the extractor when nothing is in the chamber but if that’s piece isn’t supposed to stick there, I’m thinking that might be smashing against the rim of the cartridges when chambering.
I suspect this because my latest experiments had me pushing back the shoulder of my cases using an 8x50R Lebel sizing die, which has the shoulder back a few mm even from the 8x50R Austrian.

Any suggestions for removing this if it isn’t part of how the chamber is supposed to be shaped?