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Discussion Starter · #1 ·
Hello all,
I have a few cases of Civilian Marksmanship Program 30-60 mil-surp ammuition (both Lake city and Greek Pyrkal ball) and wanted to use it for inexpensive practice/plinking ammunition for my as-yet-unfired Winchester (pre-FN model) Model 70 Classic Stainless 30-06. The problem is that the CMP ball ammo will not chamber correctly.

I tried Lake City and the bolt would barely close. With Pyrkal, the bolt still closed tightly but not as much as before. Upon extraction with the Pyrkal, the bullet stuck in the barrel and the extractor yanked out the bulletless case (gotta love that full-sized Mauser extractor). Both GI bullets showed scoring from being shoved into the rifling. On both occasions, it was extremely difficult to re-open the bolt.

When I tried two brands of commerical ammunition, the bolt closed with moderate (less than previous) resistance. There was no extraction issue whatsoever and the bullets showed no signs of touching the rifling.

I know that the bullet is being smashed into the rifling and this can cause very dangerous pressure issues. I am not going to try to fire anything out of this gun until I have the chamber checked by a competent gunsmith. My question is this... is it common for military-surplus 30-06 ammunition to have this problem in a commercial 30-06 chamber?

I am guessing that I'll have to have the chamber throat slightly lengthened to match the mil-surp ammunition. I'm ok with that because this rifle will see almost entirely USGI or handloaded ammunition and I can load to whatever length is required for the GI ball ammo. I'm just a little disappointed that my stash of GI ammo won't work. So, is this common?

Also, I am new to bolt guns for the most part. How much bolt-throw resistance should a new gun have versus a "broken-in" gun, assuming no gunsmithing has been done? Watching TV I notice that some of the "tested" bolt guns on the shooting shows seem to be operated with one or two fingers.

Thanks, I appreciate the help.
 

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That does not sound right

Have you measured the CMP ammo to verify the overall length of the cartridges? There is certainly something amiss with either the ammo or the rifle. You are correct that a trip to a competent gunsmith is in order. Let us know what turns up. All the best...
Gil
 

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I'm guessing you have a very short throat on the barrel, perhaps none at all, based on what you've described. You're definitely going to want that opened up so you don't have to seat bullets extremely deep into your case to avoid pressure problems. If it were me, I wouldn't fire a single round out of that gun until you have it checked out and most likely, the throat cut/lengthened.
 

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Discussion Starter · #4 ·
I'm definitely NOT going to touch off any ammunition until I check the chamber. Something is definitely out of spec.

I measured the two different lots of ammunition and the OAL's, case lengths, shoulder dimensions, and case neck diameters were all well within spec according to my Hornady Handbook. They also were nearly identical to a box of Eu Claire M2 ball I had laying around.
 

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Unlike 308 or 223, there is no difference between mil-spec 30-06 and civilian/commercial 30-06. If that ammo's not chambering properly in your rifle, then I think the rifle's the problem. I have a couple cans of the Pyrkal stuff, and I find it to be good quality. It also chambers, fires, and extracts properly in my Browning 30-06. I could see a bad lot or something, but if the Lake City Arsenal stuff is doing basically the same thing, I just don't think it's the ammo.
 

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Discussion Starter · #6 ·
I had read that the pressures of M2 were a little lower than typical modern commercial 30-06 loads due to Garand operating rods bending. Even if that is the case, I thought the case dimensions were identical. My Hornady reloading manual confirmed this.

I am a little surprised that the military loaded a small 150gr bullet so long. The M2 load is about the same length that Hornady gives for the 190gr spitzer.
 

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Strange, I have the same ammo, it chambers fine in my M1 Garands and Rem 700 ADL.

Yes it is lower pressure, because of the Garands long operating rod. Nominal velocities are 2800 FPS for the 150 grain load.
 
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