Need help with a 6 Beggs projec,

[AndyTaber]

I've been helping a shooting buddy who wants to have a barrel chambered in the 6 Beggs. He wants to see what it will do wuthout all of the extra brass work involved with his PPC.

Here is the conundrum. After doing a lot of reading, the general consensus for a tight no turn neck is a .272 (minimum) chamber to a .274 (ideal per Gene). After necking up a couple rounds and seating a couple of different bullets, the loaded neck size is Mic'd at .274. Is there some variation in neck thickness on Lapua 220 Russian brass? He wants to keep the chamber neck diameter fairly tight, about two to two and a half thousands over the loaded round size. So why is our loaded neck size so large?

 

[Boyd Allen]

What does the bullet's pressure ring measure. What tool are you using to measure?

 

[AndyTaber]

We used a micrometer for the measurement. The whole neck, including pressure ring (loaded some barts 65 gr) , was the same.

 

[mturner]

Double Check

I would double check the micrometers on a standard, and make sure there are no burrs on the end of the neck that were raised from a chamfering tool, or from not being chamfered at all. If you are absolutely certain that the diameter is .274", then a decision will need to be made on how to proceed. If Gene Beggs says a .274" reamer neck is optimum, then I would go with that diameter, and believe that my lot of brass just happens to be thicker. I would also check with other no-turn shooters, just to make sure that the brass hasn't gotten any thicker lately. If you have to barely turn a few here and there, at least you wouldn't have to deal with too much clearance on a more normal lot of brass. If you choose to use a reamer with a .276" neck, you may wind up with .004" neck clearance later on with a lot of brass that is typical.

Michael

 

[AndyTaber]

He has another box of brass ordered. Should be here by friday. We'll see what that tells us.

 

[pablo]

Lapua 220 Russian Brass

I bought a box of Lapua 220 Russian from Brunos last week. The neck wall thickness on that brass is a tick over .015 which would give you the neck dimension you're getting. Looks like you'll have to neck turn that brass to get what you need.