Question about new barrel

[Wenatchee Kid]

I am fortunate that I just received my M-1 from the CMP that came with a new barrel. Is there anything I need to do to break-in the new barrel? I remember my gunsmith advised me to go through a process in breaking in a new AR barrel. Just wanted to see if the same is true with a new M1 barrel. Thanks!

[Orlando]

IMO no need, fire away

[Smokey]

The usual drill is to fire a few shots, then clean it. Repeat a few times before any significant shooting. I replaced a barrel on one rifle, then used it in a DCM match. That barrel now has a tendency to drift high and right when it heats up. I later found that that effect can happen with improper break-in of a barrel.

[David Milisock]

I am fortunate that I just received my M-1 from the CMP that came with a new barrel. Is there anything I need to do to break-in the new barrel? I remember my gunsmith advised me to go through a process in breaking in a new AR barrel. Just wanted to see if the same is true with a new M1 barrel. Thanks!

The discussion about barrel break in rages. I never subscribed to it, clean it before you shoot. You're shooting an auto loader, if you want the barrel to last keep your rate of fire down. Don't run 3 or 4 clips through like your life depended on it. Clean after firing, use a nonmetallic rod, a bore guide, no steel brushes. Don't scrub and scrub, use a dry patch or 2 when done, if storing the rifle a light oil patch.

On bench rest forums I've read a few times about bores being ruined by over scrubbing. I have a 1944 sporterized 98 Mauser with a broach cut bore, I used J&J polish on it for about 100 strokes because it was a bear to clean, it shoots real well and is easier to clean.

[lapriester]

I shoot and clean. The first few cleanings I use strong copper cleaner. I'm not sure what type of AR barrel break in was supposedly recommended but I've never made any effort to follow any special procedure at all with the 16 different AR uppers, in 12 calibers, I've built and shoot sub MOA groups with. The break in they get is sitting in front of the TV and cycling the action a couple hundred times to smooth out the bolt and barrel lugs before my first 200 round or so range day. I clean when I get home.

If we were talking a custom built long range competition $5,000+ bolt gun I could understand following a strict break in but any huge, even noticeable difference it would make in a gas gun or any milspec rifle is not worth wasting good ammo on. A Garand with a couple hundred rounds worth of careful break in is still not going to ever be better, on average, than a 2-3 MOA rifle that you just went out and shot the hell out of right out of the box.

But, I might do some honest break in on an AR meant for Service Rifle comp that had a premuim quality, high dollar barrel on it.

[David Milisock]

I shoot and clean. The first few cleanings I use strong copper cleaner. I'm not sure what type of AR barrel break in was supposedly recommended but I've never made any effort to follow any special procedure at all with the 16 different AR uppers, in 12 calibers, I've built and shoot sub MOA groups with. The break in they get is sitting in front of the TV and cycling the action a couple hundred times to smooth out the bolt and barrel lugs before my first 200 round or so range day. I clean when I get home.

If we were talking a custom built long range competition $5,000+ bolt gun I could understand following a strict break in but any huge, even noticeable difference it would make in a gas gun or any milspec rifle is not worth wasting good ammo on. A Garand with a couple hundred rounds worth of careful break in is still not going to ever be better, on average, than a 2-3 MOA rifle that you just went out and shot the hell out of right out of the box.

But, I might do some honest break in on an AR meant for Service Rifle comp that had a premuim quality, high dollar barrel on it.

I have a few custom rifles and they had better not need barrel break in. I paid a fortune to have hand lapped barrels. Shoot and clean, Shilen, McGowan, Remington and Howa barrels, 3 hammer forged and one button cut.

With that said today gun smith's are what they are.

[TJT]

More gun barrels are ruined by excessive/improper cleaning than by shooting. Remember too, if you do the math (i.e. bullet time in barrel), a barrel actually only has a life span of a few seconds.
Jon

[Wenatchee Kid]

Thanks for all your input. I really appreciate the expertise of fellow shooters. One more question: the barrel, as I mentioned, is a new one installed by CMP. The CMP website advises against using modern factory ammo in a Garand due to pressure issues. Does this hold true if the barrel is new?

[Mgv744]

Try PPU ball for Garands and S-B ball for Garands ,plus CMP Creedmore for Garands. Stay in the 150-168 grain range. Fire and clean between first 5 shots and then clean every 10 shots for first 20 rounds. Avoid rapid fire during this break in. your get to go. Use a pull through Otis cable type,not a metal rod!

[jak]

The CMP website advises against using modern factory ammo in a Garand due to pressure issues. Does this hold true if the barrel is new?

The pressure CMP is referring to is the for the gas system and not the barrel. That's why you should use garand specific modern ammo or military surplus ammo. The other choice is to use an adjustable gas plug.

[TJT]

. Use a pull through Otis cable type,not a metal rod!

Use a one-piece coated steel rod and muzzle protector unless you're going to thoroughly clean the pull-thru after each use.
Jon

[Mgv744]

Yes using the wrong bullet weight and powder burn right can bend your op-rod. Garand rated ammo is the right burn rate for the Garand gas system. If you reload Hornady as a Garand data page on there website.

[Mgv744]

Use a one-piece coated steel rod and muzzle protector unless you're going to thoroughly clean the pull-thru after each use.
Jon

The Otis uses cleaning patchs you can change after pulling it through.