'Navy experimental' 308 barrel?

[xsexcess 0]

http://www.gunrunnerauctions.com/listings/...emnum=838061541

The above is a link to a M1941 listing on Gunrunner. There are several interesting things about the listing. One, the bolt and barrel are numbered the same, and two, the extra 19" barrel chambered in 308, and three the USN 'experimental' comment.

Any volunteers to try and contact the owner / find out the origin of the stories?

Mike Cobb

[webmaster 0]

S/N 9009 was a standard NPC delivery transferred on 3/16/42.

The 'US Navy' barrel I'll leave to someone who wants to speculate on its history!

[JAG06 0]

In 1965-66, the Springfield Armory made M1 Garand barrels for the Navy which were chambered in 7.62 NATO, not the commercial .308 WIN. The Navy had contracted with AMF and H&R to convert M1s to 7.62 NATO because M-14 production could barely keep up with Army and USMC demand and the Navy wanted more rifles in the new standard caliber. The early conversions used a chamber insert in a .30-06 barrel, but those were deemed unsafe to fire as the inserts had a tendency to eject during firing. As far as I know, there were no M1941 Johnson barrels produced under this program and I can't think of a reason to make any, since the Navy did not have any M1941s in its inventory. If there had been any, they would have been marked "7.62 NATO" - not .308 WIN. This may be a .30-06 M1941 barrel with a surplus 7.62 NATO Garand chamber insert, then shortened and recrowned and marked .308 by the gunsmith.

[Matt K. 0]

Well. It does have an original barrel. Think of the .308 barrel as a bonus... if it is inspected and safe to shoot, it will be a relatively cheap shooter and the original barrel will be spared.

Upon second look, take a look at the wood, especially in the photo around the magazine... looks kind of oversized. I may be wrong, but does it look like replacement wood?

[Alasdair MacDonald 0]

Uh fellow Johnsonians, I have been around Johnsons a good many years and this "USN" experimental barrel sounds like bovine scat. Possibly a sale idea. Also by reducing the weight of the barrel by shortening, you are reducing the mass at rest which will cause the barrel to reciprocate with more cererity. This in turn will upset the tension in the springs and all those designed to check this rifle as it fires. It is a domino game, and when you change one you affect the entite system. I would love to see that barrel cycle in that rifle. Anyone want to bet it will work? I'll bet it won't. Excuse me, but I have seen recently adds and now listed here that there is a difference between a 5.56mm round vs a .223 round and a 7.62X51 vs a .308. What the hell is the difference" One is metric and the other inches. Ecucate me please. Cordially, Alasdair

[Bob Lamoreaux 0]

I don't remember all the particulars, but I believe the 7.62-mm NATO is somewhat different from the .308 Winchester. I DO know that the 7.62-mm was developed from the .300 Savage, NOT from the .30-06. Bob

[xsexcess 0]

Several interesting posts. I looked at the photos of this auction listing pretty closely. The stock contour looks a lot like that of my W crest rifle, and the grey parkerized finish looks the same too. The barrel on my W crest rifle is also 19 inches. Seems likely this rifle came from the Old Benecia Arsenal.

BTW, I hate to do it, but I've got a house investment that's eating my lunch, something's gotta go. I'll be listing the W crest rifle on AuctionArms in the near future. I'll try to be as factual about it's non-standardness as I can. So I ask for your factual support in my endeavor.

VR,

Mike Cobb

[xsexcess 0]

Oh, one more thing. A 19" barrel cycles just fine (Alastair was speculating). At least mine in 30.06 does.

Mike Cobb

[webmaster 0]

As an aside, the 7.62 NATO cartidge was developed as the T65 cartridge and MMJ had a major role in its development.

[Matt K. 0]

OK, I'm ignorant.... what is a W crest rifle?

[LoboMike 0]

FWIW I emailed the seller and asked if the .308 barrel had been fired, and the response was no and they couldn't test fire it for me. They expressed they would not guarrantee it cycled and/or functioned in the M1941.

I was thinking ammo cost savings.

HTH

[MAS 0]

but I believe the 7.62-mm NATO is somewhat different from the .308 Winchester.

The case is the same. The pressures they are loaded to may be different. The real diff. is in chamber size of the firearms, I believe mostly in the throat.

[JAG06 0]

Here's a good discussion of the difference between 7.62 NATO and .308 Win:

Fulton Armory

The bottom line is that you can always shoot surplus 7.62 NATO ammo in a rifle chambered for .308 Win, but not visa-versa because military 7.62 NATO chambering may exceed SAAMI headspace standards.

[Alasdair MacDonald 0]

Class is in session, professor MacYak instructing.

Here is the poop on .308 vs 7.62x51

1. The round was invented by the U.S. Army and is basically a 1/2 " shortened .30-06 round and desiginated the T-65 introduced in 1952.

2. It was adopted by U.S. military in 1954 even so they did not have any rifles chambered for it and did not until 1957.

3. It is only @ 100 fps slower at the muzzle than the .30-06.

4. Winchester requested permission to add their name on the round and make it commercially available in the .308 designation. Permission was given to them by the U.S. back in 1952.

5. The basic difference in the interior of the round is that the military case uses a thicker web at the bottom.

6. Commercial producers making head space guages make no difference in using this guage for either the .308 or the 7.62X51 as they both headspace on the shoulder with the same specifications.

7. The only difference is where you want to use a specific bullet and get a chamber reamer that accomodates this bullet. Target shooters have known for years that if the bullet just slightly touches the leade, (the begining of the ramped rifling) one gets the best accuracy as the bullet does not have to jump before contact with the rifling. The downside of this is that it also increases interior ballistic pressures so you should not be using max loads.

8. Headspace can start at a low measurement and increases with wear and pressure until the headspace reaches an unsafe measurement with a no-go guage. The basic measurement differences is found in the leade/freebore. That is why you can get a chamber reamer for a specific bullet depending upon your use. I have a Stoner SR-25 that says to only use 168 grain Spitzer boatail bullets as the leade is cut for this bullet for accuracy.

9. For all practical purposes, they are the same.

Cordially, Alasdair