7.62X54R - issues with .308 bullets

margiesex · June 5, 2009, 12:50 PM

Hey out there. Just rolled by this site today and thought I'd drop in. I just picked up RCBS dies (full size and neck size - plus seater) for my daughter's friend's Nygant (?) in 7.62x54R. The Sierra Manual I have lists all kinds of loads - all pushing a .308 bullet. Well, I full length resized, the bullets fall into the case! So, I neck resized and completely removed the decapper/expansion ball - aka went with the neck resize - and...yep, the .308's fall into the case - well, I can push them in with finger pressure. They sure would fall out with the recoil.

What am I missing?

My hunch is I have to move up to .310, .311, or .312 bullets, but which one, or all?

Oh, and cling to God and your guns - you can't go wrong!

Margiesex

azar92 · June 5, 2009, 01:53 PM

The Mosin-Nagants are one of those guns that has a varying bore diameter. Finnish Mosin-Nagants are typically .308 and are more prized for their accuracy than others (more expensive too). The more common, less expensive Russian Mosin-Nagants can be anywhere from .310 to .314. You really need to slug the bore first to know what size of bullets you need to use. Many sizer dies for 7.62x54R come with two expander rod assemblies, one in .308 one in .311. Some only come with one (though the other size is usually available at additional cost). It sounds as if your die is sizing to .311 which obviously is not giving you enough neck tension to hold the .308 bullet.

Slug the bore first. Here's some basic instructions for slugging a Mosin-Nagant.

If the bore diameter does measure out to .308 (less likely), order the additional expander rod assembly from RCBS and use the bullets you have. Heck, they have good enough customer service they might send it to you for free. If it comes out bigger than .308 find a more appropriate bullet.

June 5, 2009, 12:50 PM	#1
margiesex Senior Member Join Date: June 5, 2009 Location: Levittown, PA Posts: 210	7.62X54R - issues with .308 bullets Hey out there. Just rolled by this site today and thought I'd drop in. I just picked up RCBS dies (full size and neck size - plus seater) for my daughter's friend's Nygant (?) in 7.62x54R. The Sierra Manual I have lists all kinds of loads - all pushing a .308 bullet. Well, I full length resized, the bullets fall into the case! So, I neck resized and completely removed the decapper/expansion ball - aka went with the neck resize - and...yep, the .308's fall into the case - well, I can push them in with finger pressure. They sure would fall out with the recoil. What am I missing? My hunch is I have to move up to .310, .311, or .312 bullets, but which one, or all? Oh, and cling to God and your guns - you can't go wrong! Margiesex

June 5, 2009, 01:53 PM	#2
azar92 Senior Member Join Date: April 16, 2009 Location: Utah Posts: 209	The Mosin-Nagants are one of those guns that has a varying bore diameter. Finnish Mosin-Nagants are typically .308 and are more prized for their accuracy than others (more expensive too). The more common, less expensive Russian Mosin-Nagants can be anywhere from .310 to .314. You really need to slug the bore first to know what size of bullets you need to use. Many sizer dies for 7.62x54R come with two expander rod assemblies, one in .308 one in .311. Some only come with one (though the other size is usually available at additional cost). It sounds as if your die is sizing to .311 which obviously is not giving you enough neck tension to hold the .308 bullet. Slug the bore first. Here's some basic instructions for slugging a Mosin-Nagant. If the bore diameter does measure out to .308 (less likely), order the additional expander rod assembly from RCBS and use the bullets you have. Heck, they have good enough customer service they might send it to you for free. If it comes out bigger than .308 find a more appropriate bullet.