.311 bullets -

[pig ranch deadeye]

In hand-loading a thirty magnum round, using a slow powder, can a .311 diameter bullet be used instead of a .308 diameter? The difference of three thousandths is slight, perhaps it would not matter. I was looking at some 203 grain spitzers in .311 and was wondering how the would do in the .300 Win mag. Presumably this would increase pressure. And velocity too? I have hand-loaded unjacketed, lead .44 magnum bullets, diameter .429, in my .416 Remington and it worked fine.

 

[del2les]

It varies. Individual rifle bore sizes are not equal, and as you have already pointed out, it will increase pressure. I have loaded a lot of older .310-.311 bullets in old 30-06's with worn or longer throats, and they did work ok. Start your load charges below the minimum manual load and work up slowly.

Problem with this procedure can be jacket loosening its grip on the core due to the "drawing" of the jacket, and after exiting the bore, causing less accuracy. However, the amount will depend on several factors.

A few years ago, I bought a cheap and sizable amount of .310 AP bullets designed for the old 7.62x54R, and while I had designs on loading them in my 303 Brit, they did work in one of my '06's.

 

[pig ranch deadeye]

thanks for the info