remington 40x question

[beemanbeme]

A friend has a rifle that has a standard M700 (blued) action and a SS heavy barrel.  There are no markings on the barrel except next to the receiver the small - 1/8--3/16th letters "ref". He sez it is a 40X from the custom shop.  Without "Remington" on the barrel, I find that hard to believe. 
Help me out here. 
Thx in advance

[jvs]

Believe or not beemanbeme, Remington does indeed produce work in their Custom Shop without putting the Remington name on the piece.

I have a friend, who owns a few Remington 600's and 660's (40x Actions, btw).  One of them is a Remington 660 in 6.5 mag.  After almost 40 years of range shooting and hunting, the barrel starting 'cottonballing', and was throwing off accuracy.  He sent it back to Remington to see what could be done.  They ended up replacing the barrel.

When it came back, there was no Remington name on the barrel... Just 6.5 Magnum.

When my buddy saw this, he got on the phone right away and asked Remington why they didn't put a Remington Barrel on the rifle.  They told him the Barrel came from the Custon Shop and they don't have barrels there with the name on.  They told him if he ever ran into problems explaining to someone who wanted to buy the rifle, he should show them the letter he got from Remington, detailing the work that was done to the rifle.  He and I believe that barrels from the Custom Shop are NOT the same grade of barrel that Remington uses in production, but we have no proof of that.

I know it sounds odd that they would use barrels without the name on them, but they do.  So if your friend can get a hold of the letter that came with the rifle originally, it might be a big help in the future.

[beemanbeme]

Well, son of a gun.  Thanks for the info.  I knew that custom shop barrels didn't come from the common stock but I didn't know they weren't roll marked.
That brings us to the second question: What is cottonballing?

[jvs]

A 6.5 Mag carries alot of juice in the casing, as do some other calibers.  There is a torrent of fire and expanding gas in the first millisecond after the pin hits the primer and the bullet makes its way down the barrel.  So much so that the breech end of the barrel starts to erode, in the area where the bullet and casing seperate.  I have heard it called a 'cottonballing' effect because thats what it looks like when you look into the barrel.   It looks like a cottonball would fit in that space nicely.

Somewhere between 400 and 1,000 shots through a 6.5 mag and that barrel erosion becomes so great that gases are no longer mostly behind the bullet, but can escape around it, which will eventually throw off accuracy.  You can't get away from excessive barrel erosion in a 6.5 and alot of other calibers. Each and every shot brings you closer and closer to the day the barrel is done with.

I doubt 'cottonballing' is the correct term, but that is easy to understand.

For 40 years his 660 6.5 mag would clip holes at 100 yds at the range.  It opened up to a 2" group and he knew something was wrong.  After checking everything imaginable, he sent it to Remington.  The diagnosis was Erosion....but I have heard it called 'cottonballing'.   It makes your bore look like a big Q-Tip.

Ever since I heard Remington uses unmarked barrels,  I have it in my head when I go to a Gun Show, that if I see a Rifle that the seller might 'think' is a Remington, but isn't sure because the name isn't on it... I may just take a chance on it being a Custom Shop or a Remington replacement, and buy it.  Without a name and back-up proof, it could be a great deal.  Or......

[sniperVLS]

I believe the proper term is 'throat erosion', unless we are getting our lines crossed and I'm misinterpreting 

[jvs]

yeah... what sniperVLS said.

Throat Erosion is the proper term for the condition of gas escaping around the sides of the bullet due to erosion of the barrel steel due to extreme heat conditions where the bullet leaves the casing.  It grows a little deeper and longer with each shot even with the best of powders.  Chroming the bore may slow down the process but nothing will stop it.  Eventually, the barrel will need replacing, especially on the high powder volume magnum calibers.   

With a caliber like the 6.5 mag, if you actually get to 1,000 shots without replacing the barrel, you can consider yourself lucky.  My friend estimates that he has nearly 1,000 shots out of his in 40 or so yrs.

I have a Remington 673 in 6.5 mag and mine has not eroded one bit yet. 

( But I haven't shot it yet either.....but I will )

[beemanbeme]

Thank you.