7.62x54R - Page 2

tobnpr · April 12, 2018, 05:22 PM

All M39's were spec's with .310 bores per the reference below (great site for all things MN).
I've never been concerned about .311 bullets (the 174 grain SMK), it's reasonable to expect a small amount of bore wear anyway- and .001 is not oversize enough to be a concern with overpressure on typical loadings. They'll swage down to seal tightly and work well in my experience.

Worse to have a .308 tumbling down there loosely with no effective gas seal.

http://7.62x54r.net/MosinID/MosinSpec.htm

April 12, 2018, 05:22 PM	#26
tobnpr Senior Member Join Date: August 1, 2010 Location: Tampa Bay Posts: 4,556	All M39's were spec's with .310 bores per the reference below (great site for all things MN). I've never been concerned about .311 bullets (the 174 grain SMK), it's reasonable to expect a small amount of bore wear anyway- and .001 is not oversize enough to be a concern with overpressure on typical loadings. They'll swage down to seal tightly and work well in my experience. Worse to have a .308 tumbling down there loosely with no effective gas seal. http://7.62x54r.net/MosinID/MosinSpec.htm __________________ Remington 700/Savage Rebarreling /Action Blueprinting 07 FFL /Mosin-Nagant Custom Shop/Bent Bolts Genuine Cerakote Applicator www.biggorillagunworks.com