I am trying to seat Winchester primers in brass that takes large rifle primers. I have uniformed the primer pocket with the correct depth K&M primer pocket tool and in frustration also with a Wilson primer pocket reamer. The primers start to seat OK, but they are hard to seat the last half. You can't feel them bottom out, and it is hard to get them the last little bit to sit below the base of the case.

I even set the K&M uniformer to cut 50% deeper than normal, and the primers are hard still hard to seat. I guess
that I have a batch of primers that are too large in diameter.

The brass is 7.62x39 from PMC, Winchester, and Lapua.

I've loaded ammo for 45 years and never had this kind of problem. What am I doing wrong?

I think I found the problem. I measured the Winchester primers and they were .212 in diameter. I measure some
from a later batch and they were .210 inch, and seated normally. Has anybody else run into this???
Does anybody know the manufacturing tolerances for primer diameters?

Very interesting as Artie Johnson used to say! I have found some that seemed to be a bit taller, but never before wider. You should have known for sure that it was the primers when three types of brass gave notice. The cure is to find some former proof load brass with expanded primer pockets, or perhaps return to manufacturer for out of spec product. Interesting to see the caliber of choice for loading...

Care to expand on the loads? I am a big fan of loading for the .308 X 39 and use mostly AA1680 or VV 130, though I have just brought a pound of LiL gun for some 110 V-Max load attempts.

Cannon beach this Sunday... Yippee

I am just about to build a 308x39 to go along with my two mini-mausers in 7.62x39 and my Ruger 77 that came from
the factory as a 7.62x39. I set the barrel back on the Ruger due to excess headspace. My intent with the 308x39
is to try to compete with the 30Br crowd with a cheaper solution. Kind of reverse snobbery.

I am finding more satisfaction with the smaller cartriges lately. I have been from .22 Hornet to 416 Rigby and
now am playing with 6mmbr, 7mmbr, and 7.62x39. As for loads, it will be a month or so before I have some
results I want to share. I do have 32 pounds of H116 which is supposedly surplus W680. It is supposed to be
very close to A1680 in burn rate.

For a hoot I took the Ruger in 7.62x39 on a prairie dog shoot in Montana. It didn't blow up the dogs, but
none of them got away. For the .310 diameter bullets I am using 110 grain cast bullets from Oregon Trail
Bullets. If you ask nicely they will provide normal 308 bullets sized to .310.

Tomorrow I will be stalking rockchucks with a mini-mauser shooting the .310 123 grainers from Hornady. I wish
Speer made a TNC bullet in .310. Next week I will try shooting the .308 diameter TNC at rockchucks. I don't
think the bullet will have any problem upsetting two thousandths of an inch more to fill the .310 groove.

I built a rifle a few years ago using a reamer that in essense had a forcing cone to reduce the .310 bullets
to .308. I think it came from Clymer, but I am not sure. It worked well.

Let me know what rifle you are using, and what bullets work for you.

Two rifles actually, first a Sako vixen, opened the bolt face to PPC and Bill Wiseman & Co supplied the barrel and stock work. Length is 22" and I do believe 1 in 10 and .308 diameter. The second is a 16" upper on my Colt AR15 system, and this should be 1 in 12 twist. I "ASSUME" this to also be a .308 Diameter, but it might not be! and I shoot only .308 handloads with great accuracy in it. Mainly the Speer TNT 125's bulk packed. I like the nose configuration for feeding, though recently the Sierra 155 Palma bullet has had some fun play in the Colt. In the Sako I shoot Nosler BT's at 125, and 150. I have taken several deer and a mountain lion with this little rifle and have been quite satisfied with the terminal performance. The little cases are very favorable when the ranges aren't extended too far out. Or when bullet weight is kept down relative to bore size. I think of the .300 Win as being best with 200 gr, the '06 with 180's, the '08 with 165's and the .30/30 with the 150's. I think the 7.62 is the equal of the .30/30 for all practical purposes. In an accurate rifle, it will shoot very very well. Best 5 shot 200 yard group was .8" and that was during load developement! Have fun!