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Old January 2, 2013, 06:54 PM   #1
ffs1942
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Buying CMP M1. 30-06 vs 7.62?

I'm considering buying a CMP M1. I note there are a limited number converted to 7.62, I believe formerly USN issue.

I would prefer 30-06, as this is historically the rifle my father used and that won WW2 and Korea, but the 7.62 offers logistical advantages in a national calamity.

As a retired National Guardsman and member of the Retired Reserve it would be my moral duty to immediately report to our nearby state HQ in event of a great catastrophe, like a nuclear attack, etc. Presumably I would be issued new uniforms, TA50 and a M4 or M16, but if supplies were short, it would seem wise to report with what uniforms and gear I had left and with a compatible weapon. 7.62 would be the obvious choice. Likewise, if the government became tyranical, 7.62 could be more easliy obtained than an obsolete caliber.

Then again, how does the 30-06 compare to the 7.62 in competion? Also, don't these 7.62 conversions have reliability issues? If it had been that easy to turn M1's into 7.62's, as Beretta did, the M14 would never have existed.
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Old January 2, 2013, 08:24 PM   #2
FALPhil
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The only 308 Win rifles that I am aware the CMP sells are not Navy rifles, but rifles that the CMP puts together with military parts and new Criterion barrels. They call them "Special Grade". They run about $1000. They do sell some Navy barreled actions, but they are just barreled actions and run $350.

The 308 rifles are just as reliable as the 3006 rifles. All other things equal, there is no advantage in mechanical accuracy between the 3006 and the 308. However, in practical terms, the 308 causes less fatigue, and over a course of fire, the typical shooter will perform better with the 308 due to less fatigue.

As to ammo availability, I think it is probably a wash. However, the full length Garand is pressure sensitive, and you can bend the op rod with the wrong ammo, unless you use a gas regulation device like the Schuster Plug. An alternative is to send your Garand to Shuff's for a Mini G conversion. The conversion shortens the op rod and reduces the opportunity for damage do to improper pressure curve.
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Old January 4, 2013, 07:55 PM   #3
mxsailor803
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FALphil- any idea if the special grade .308 will handle full power loads or should it be reduced pressure loads like the 30-06?
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Old January 4, 2013, 08:24 PM   #4
FALPhil
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I don't know. The 308 doesn't have the gas volume that the '06 does, so the pressure curve is different. If no one else chimes in, this may be a question for the ODCMP forum or jouster.com.
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Old January 4, 2013, 08:26 PM   #5
mxsailor803
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That's kinda what I was thinking with the pressure diffences. A little bit of a Resident Evil fan? lol
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Old January 4, 2013, 09:22 PM   #6
tahunua001
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FAL phil, CMP is listing surplus barreled Navy actions and sell just about any part you would need to get them up and running. the special grades are indeed criterion barrels with mostly new parts. if the rifles indeed function properly I would say that they would be a great bargain over an M1a or norinko M14 knockoff.

however I would say that retired members, no matter whether they have been recalled or volunteered, would be placed in support roles, not combat roles. you would be the ones manning the mess halls, sitting behind desks and and supply tasks that could be handled by LLD personell. also in the event that there was crippling shortages of weapons to issue, a 308 would probably be pretty hard to feed for most bases, I know on my carrier we had M14s for drilling, shark watches, and anything that 5.56 couldn't handle but 50 cal was overkill for but we had very limited supplies of ammo for them. an AR15 or other evil black rifle would be much more practical to supplement existing stores as you would use the same ammo as everyone else and if your rifle broke USGI parts are interchangeable, if the trigger group broke then you will have hit the jackpot(three round burst, here we come )

EDIT: thank you for your service!
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Old January 5, 2013, 08:09 AM   #7
Bart B.
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mxsailor803, I've no idea where you got the idea that 30 caliber Garands use reduced loads compared to commercial loads with SAAMI specs for peak pressure and/or velocity. Same for the 7.62 NATO Garands used by the USAF and USN for service or competition. Both rounds have had the same MIL-SPEC pressure limits at 50,000 cup since their inception. And both versions have had thousands of commercial ammo, either .30-06 or .308 Win. fired in the respective ones without issue. SAAMI specs for .30-06 are the same as MIL-SPECs as far as pressure's concerned. And for the 7.62 and .308 rounds, the specs are close enough, SAAMI's 52,000 cup, and there's no danger using either in a 7.62 Garand.

There were no reliability issues in the USN and USAF converted 30 caliber Garands to 7.62 NATO by just replacing the barrel. In the initial stages, it was noted that the port pressure of the NATO round was lower than the 30 caliber one, so the barrel's gas port had to be drilled out a bit on the barrels made at Springfield Armory in MA. In service use, there were no problems.

For 30 caliber Garands that had the chamber insert installed, there were issues. Sometimes those inserts came out with the ejected case. This idea was quickly scrapped. The USN Small Arms Match Conditioning Unit (SAMCU) sold all their chamber inserts to some commercial outfit for retail. So only those CMP 7.62 NATO Garands with the original Springfield Armory 7.62 NATO barrel should be considered safe to fire. Check out this page for details:

http://www.thecmp.org/Sales/762Garand.pdf

Here's the straight scoop on CMP's sales of 7.62 versions:

http://www.odcmp.com/Sales/m1garand.htm

Scroll down to the section titled: "Navy M1 Garand Barreled Receivers"

Accuracy wise, the 7.62 Garands were hands down more accurate than the 30 caliber ones. Their 1:12 twist barrels were better suited for 150-gr. ball and 172-gr. match ammo's bullets. The 30 caliber ones 1:10 twist was way too fast for best accuracy. This is one reason why the targets used in competition and training had their scoring rings reduced 3 years after the NATO round was first used in matches in 1963. Commercial match ammo was tyically more accurate than military match stuff. The USN SAMCU air gauged all the 7.62 barrels they got from Springfield Armory and those with groove diameters uniform and at .3076" to .3079" were set aside for match versions for the USN Rifle Team. They easily shot commercial match ammo into 4 inches at 600 yards; no 30 caliber match grade Garand ever came close to that.
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Last edited by Bart B.; January 5, 2013 at 08:42 AM.
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