M14 Re-Barrel - Parts Kit vs. Criterion

[fatcatbestcat]

Right. Now that I've messed around with this M305 for a couple months now, I'm considering the possibility of upgrading the barrel in the future (if I'm unitizing the gas system, might as well, right?).

I could wait for an IDF parts kit to go on sale (or get it now for like ~$1,000) or just buy a new Criterion barrel (22", GI contour, either anodized or S.S) for about $450 - $550

I've done a few re-barrels, but on bolt-action rifles, and I've never dealt with a semi-auto before.
Is there anything weird I'd have to do for headspacing or whatever?

 

[Claven2]

Weird?

Basically with a new barrel, you.need to install it and team the chamber to final dimension.

 

[1-trident-1]

as in life, it's all about timing, seconds count.

 

[fatcatbestcat]

I should probably elaborate on my question; Normally, in a bolt action (with a short-chambered barrel), you'd remove he bolt and put your reamer all the way through (the action is a straight tube).

The M14 receiver is boxed-in, so how do you fit the reamer in?

 

[tiriaq]

Use a pull reamer. The barrel is indexed, the stripped bolt installed. The reamer is inserted in the breech, and a rod from the muzzle is attached. The reamer is turned while gentle pressure is applied to the bolt. When the bolt drops to locked, the chamber is correct. Fast and effective.
The alternative is to remove the barrel, ream, reinstall, check, remove, ream, and repeat until headspace is correct. Or the chamber is cut too deep.

I wouldn't replace the original barrel unless there is a reason - excessive headspace, poor accuracy, etc. A factory barrel may shoot quite well.

 

[MiniMe]

I'd go criterion.
Got one and it shoots better than my m1a standard.

 

[Claven2]

You either use a pull through reamer, or you incrementally ream between trial fitting the barrel and bolt.

 

[45ACPKING]

barrel to be installed must fit hand tight at 15 to 20 degrees off TDC to be acceptable to use.....
if it tightens up before it hits 20 degrees off TDC , the torque shoulder will need to be relieved while maintaining a 1 degree undercut on the shoulder.
if it tightens up past 15 degrees , then the shoulder will need to be roll peened back to create more shoulder..... or use another barrel that hand tightens between 15 and 20 degrees.
Brownells sells the Clymer Match .308 pull thru reamer kit for the M1A/M14 chamber.
very easy but use lots of fluid..... I like Rapid Tap for this job.

**edit to add , torque requirement for correctly drawing the barrel to index is between 80 to 90 foot pounds. Time the barrel to the receiver off the GAS PORT , not the feed ramps.

 

[maxman1]

Or contact jonh172 and ask if he's still installing barrels.

 

[Jacobean]

Or send the rifle and parts kit/barrel to M14Medic. There's a reason he's a staple here.