300 Norma Match Reamer Spec

[300SALRH]

Cleaned neck of my Norma brass measures just over 15 thou. Both Nosler CC 155gr and Barnes TSX 150gr measured have a .304 diameter. Assuming this measurement will be applicable to other .308 bullets brings a loaded neck to .335. The base of the Norma brass measures .5775 and diameter just under the shoulder .556.

What neck diameter would you guys recommend? .338 to tight and would a .340 be saver option given that the rifle will sometimes be used in environment where dirt can not always be kept out.

Would a tight spec around the base help with the management of primer pocket expansion and how tight would you recommend?

Perhaps a reamer print out there that someone can share that already incorporates all these requirement?

Going to spec a 0 freebore and use a throat reamer.

 

[dkhunt14]

If you go tight at back end and don't have special dies, you will get bolt click. Yes it might help with pockets but you need to be able to size the back of case.

Personally I like tight necks where I turn to match gun. I believe they give better concentricity and bullet tension because the brass is now even all the way around.

Nothing is wrong with zero freebore and throating it to what you want. Matt

 

[300SALRH]

Thanks Matt. Planning on sending the reamer print to Widden for a custom FL Bushing die.

 

[tuttlefarm]

You might want to get a different micrometer, I have never seen a .308 bullet measure only .304..........
John

 

[300SALRH]

John, THANKS for pointing that out!!!! Double checked with two micrometers and my vernier is about 1.5 % out. always were under the illusion that bullet are a little smaller in diameter but never verified how much.

Should check the calibration more often on the electronic vernier. Almost cost my reamer. Thanks agian.