Sizing for .308 bore

[docone31]

Hey guys, I have been reading, and reading this forum. Basically, I have a gazillion .312 castings. I have a mess sized to .311.
Now, I plan on exclusively running paper patched castings through my .303 Enfield.
How does a boolit sized .311 with gas check work in a .308 bore? Has anyone done it?
I once got a box of Herters 150gn jacketed to .309. They shot great, but, I was nervous with each shot. I had read somewhere that .311 is a good fit. I have been sizing to .309. Ok so far, minimal leading, ok patterns, powder charge to minimum for 150gn. The castings are 155gn.
Unsized cases, the gas check almost fits into the neck of the cases, both .308, and 30-06.
Any input on this?

[garandsrus]

If the rifle will chamber the .311 and .312 slugs, you should be just fine...

You powder charge might be a little strong though if you are using the minimum loading for jacketed bullets. What cast boolit are you using? The Lyman manual has loads for several different boolits with various weights.

John

[docone31]

I have the Lee 155gn, and Lee 185gn. I use 4895.
They are good strong actions, Mauser, and 03-A3.
I am mostly wondering about the .311 sizing.
Always in the quest for the grail.
Of course, someone already invented the wheel.
I have this Yuppie friend, who built a Palma Rifle. He does not compete, just goes to the range and slowly fires off 50rds. I had to tell him about reciever sights and globe front sights.
I had to help him fix his bedding, install his recoil pad with him, and show him how to sand the stock to fit him.
He drives me nuts.
The .309 works ok. Easy to load, chamber, and clean up after. I sure could use some start up data for 4895 however, perhaps that is the key. Might tighten up the group a tad. Both rifles are heavy barrel cut rifling. I want to try paper patching the .30s also. I have this theory that the paper will polish the bore which I believe will improve jacketed groups some. I know when I worked in a bindery, the paper sure produced a smooth finish on the metal.

[Boomer Mikey]

It takes less than 1000 PSI to push your lead boolits through the bore... no big deal when "light" loads are typically 10,000 PSI or more.

Your 303 has a SAAMI pressure limit of 49,000 PSI.

Slug the bore and try to use boolits 0.001"- 0.002" larger than the groove diameter; witch, in the case of the 303 is more likely to be 0.313" - 0.314". Your 0.311" - 0.312" size boolits may be too small resulting in heavy leading of your 303 rifle's bore.

The Lyman Reloading Manual is a wise investment and the Lyman Cast Bullet Handbook is another. Anyone shooting cast bullets should have at least these two books.

Asking strangers for loading information is like asking strangers which stocks to buy... Verify information with an authoritative, reputable source.

Some additional data to apply to loading your 303 or any milsurp rifle:

http://www.surplusrifle.com/shooting/castbulletloaddata/index.asp

http://www.surplusrifle.com/shooting/castingcouch/index.asp

http://castboolits.gunloads.com/showthread.php?t=13425

Boomer :Fire:

[docone31]

Boomer, you have taken a lot of time and provided me with some good guidlines.
Thanks, I take it to heart.
My .303, I will paper jacket to .3135. This I am set up to do and have several boxes of them ready to fire up.
My .30 cals, there is the dilemma. Lead, or paper.
I do not rely on internet information and forge ahead blindly. I have gotten good responses though that I have found to be ok. They have really helped.
All my rifles shoot much better than I can. A lot of what I do is kinda like hanger flying. I do love the sport. The more I learn, the more I feel involved.
I do, however research all loads.
I am set up to size .309 with cast for .30 cal. I want to try paper sized to .311 for the .30. I had heard it works without incident.

[Ricochet]

The key is whether the loaded rounds chamber and extract easily.