.308 or .338?

[Tim K]

It does but, in order to make it fit the magazine, you need to load the rounds to a short OAL which will increase the cartridge pressure.

With 123g SMK's, you can easily load to 2.800" without pressure problems. A small compromise from the 142's, but not terrible.

[cysoto]

With 123g SMK's, you can easily load to 2.800" without pressure problems. A small compromise from the 142's, but not terrible.

I have only seen it tested with 142 grainers and it was piercing primers left and right.

[MarkCO]

I have only seen it tested with 142 grainers and it was piercing primers left and right.

Sure it was not the 6.5 Creedmore? Those are higher pressure and can have primer problems. That or a just loads that were too hot!

I ran hundreds of pretty stout 142s through my AR-10 .260 with no pressure signs at all. For accuracy reasons, I dropped back to the 123s in the gas gun.

[Hoser]

I have only seen it tested with 142 grainers and it was piercing primers left and right.

That shooter learned his lesson. He was trying to use the same powder charge from his bolt gun ammo to his semi ammo.

One caliber + two different guns = two different loads.

I have a semi (LaRue OBR) in 260. 123s on top of H4350 is perfect. I tried 139/ and you have to seat them so deep you end up eating up all your powder space.

[cysoto]

That shooter learned his lesson. He was trying to use the same powder charge from his bolt gun ammo to his semi ammo.

One caliber + two different guns = two different loads.

I have a semi (LaRue OBR) in 260. 123s on top of H4350 is perfect. I tried 139/ and you have to seat them so deep you end up eating up all your powder space.

Yeap, that's the same person I was talking about!