Replacing a CETME barrel

[timmyt]

I picked up a rifle that had the welded flash hider. The idiot I got it from tried to file the flash hider off...thankfully not much. It just looks dumb. I picked up a new threaded barrel and would like to replace the existing barrel/flash hider.

How hard is this to do? Remember I am a rookie to the CETME. I picked up the Armorers manual but it seems vague regarding this.

[jfowl31]

IMO, the cetme HK style rifles are the hardest rifles to do a barrel replace on....

you need to locate the barrel pin, drill access hole in receiver, drive pin out, press barrel out, remove triple frame...

then press in barrel to the magic spot, this magic spot has about 3-4 thousandths of play at MOST, reinstall triple frame making sure its dead level, so it shoots straight, end mill, drill, ream hole in barrel, install pin, weld/fill hole in receiver, refinish entire rifle.

its WAAAY more complicated than that, but that gets you an idea. If you are confident in pressing, and doing precision work and stuff, you've come to the right place to have folks walk you through this stuff. If that sounds a bit overwhelming, perhaps the better option would be to cut, recrown and rethread the existing barrel for a new FH.

Good luck with it!

[Otis61]

He's right. It's hard. And you will run in to some tough spots. But it's doable. If you have a problem post it. There is a huge amount of knowledge among the people on this forum. And they like to help.

[mprtech]

Are you in WI by chance?

[remauto1100]

I feel your pain! I have a new cetme barrel that I am installing into cetme trunion. I am up in arms as to what to do for "proper" barrel depth into trunion. I started barrel (with a press) down into the inside face of the trunion (bolt end) and it went in nice and smooth. But I am not sure how much of the barrel (chamber face) should protrude from the inner trunion face so as not to give a false bolt gap reading. Should the bolt face just touch the barrel when the bolt is locked up with proper bolt/carrier gap or ????
I am not sure which to pay attention to first. The bolt/carrier gap or measure that after the barrel is pressed into the trunion and then measure and adjust via the rollers/oversized rollers if needed.

Mike

[rustypirate]

Press the barrel from the rear of the trunion (bolt side) to the front and stop when there is roughly 1/16" of protrusion into the trunion left. then insert the bolt carrier assembly and start checking the bolt gap. It should be WAY too large at this stage, but you can work it down to where it needs to be in itty bitty steps. You want to start with the smallest rollers and most worn out parts in your rifle for this, and you want to stop pressing when the bolt gap is just at or slightly under .020". The bolt parts rollers, locking piece, bolt head will wear in slightly until the parts all mate up fully, and this will cause a loss of bolt gap by a few thousandths, so expect it. This arrangement will allow you to press the barrel to give you full wear time on the pre-worn parts, then still allow you to replace them with new parts much later to extend the time between needing to repress again. If you only achieve correct bolt gap with new + size rollers to begin with, then as the rifle wears in the parts, you will not be able to compensate with the larger size rollers as they have already been used.

[M1 Tanker]

There is a sticky at the top of the Forum called CETME FAQ :) here is what you need to know.

http://www.militaryfirearm.com/Forum/showthread.php?t=848

[hulygan]

why replace the whole barrel. Is the flash hider welded, or soldered? If welded can't you just cut off the hider and rethread? If soldered JUst heat with a torch and remove with pliers. if you decide to really repress the barrel and replace it i can post some pics and measurements on a DIY barrel press. and if you don't want the barrel i can buy it off you.

[woofert]

timmyt,

in addition to the link Tanker posted, heres one with some details on how I did mine.

TAKE NOTE!!!!!

I'm a "shade tree" gunsmith, what I did worked for me ONCE!!

I've not done it to any other rifle but mine.

please read all the info/posts you can on the suject as there are folks on this web site with much more expericance in this matter than me, I'm no expert

Woofert


http://www.militaryfirearm.com/Forum/showthread.php?t=506

[Anthropy]

Don't cut the barrel yet. The break should be pretty easy to remove. See the FAQ, there is a pin at the 6pm location of the break. Don't give up yet, give it a try first.

[drine]

In all honesty the barrel change wasn't that bad for me. I did some things I shouldn't have and gauled the first barrel but the second barrel went smooth. The refinish work is the b-yatch. That wouldn't be so bad except for my lack of tools.
If your present barrel is accurate at all, don't mess with it, swap the flashider. drine

[Seattlefungus]

I concer with those that say use the rebarrel only as a last resort. I'd check your gap 1st. If that's good I'd really think twice before junking the barrel. If the rifle is a Century Build. They pin the barrels in to the trunion before welding them into the receiver. (at least the receivers don't come with barrel pin holes on them them) and I've never seen Pin holes on any new Century receiver . As they do nothing to there rifles that would come under the heading of "Extra" work, I find it difficult to beleive the'd take the time to cover the hole and grind the receiver smooth to make a nice finish... If they used the ATF approved silver solder, a MAPP gas rig from Home Depot will melt the solder. If welded, (Probable as Century is cheap), follow the instructions in the thread mentioned by Tanker...

[jfowl31]

Seattle... I don't know for sure if this has ever been totally confirmed, but the general concensus is that Century never demilled the barrels from the trunnions when they got the kits from spain. So all the CIA cetmes are just as worn out as they were when they left the battlefields... some of them were out of spec.... thus the bolt grinding. If they had taken the time to repress the barrels, I doubt the CIA Cetme would have a bad name today! Any other issue they have is quite small compared to a repress.

It reminds me of a used car salesman just passing off junk cars without fixing them.

[Seattlefungus]

Yeah Jord, I know what you mean. I took a chance last year and bought two used CETME barrels from Centerfire. The damn things looked like they came from unissued CETMES. Parkerizing was good, barrel great. Then I bought some barrels from Century. They looked like they'd been run over by a tank. They still had the triple frame on them and they were crushed, no Parkerizing left, barrels pitted, only thing I ever sent back, they still made be pay freight both ways...

[remauto1100]

In my case I received my cetme kit from centerfiresystems with no barrel stub in the trunion. They must have press them out before shipping them out the door. The new barrel is in the white and was in the brown paper you typically find GI stuff in here in the U.S. military. Barrel was of course already threaded for the Flash hider.
My barrel went into the trunion very smoothly with a 12ton press. Now all i gotta do is start taking measurements to get a good .019-.020 bolt gap and that will be that.
I figure I will shoot a bore laser down it to get the sights lined up for windage. I'll mess with elevation when the thing is ready to fire.

[jfowl31]

the new kits come with new barrels... the old ones didnt.