Am I completely screwed?

[pjm204]

Everything was going well until I got to the barrel pressing stage. I pressed my barrel in and pinned it where the cut was(Big mistake!), I then pinned it but the pin would only go in half way, no matter how hard I tried, I then cut it off, and pushed another pin in halfway from the other side, I knew this was terrible so I did a small weld on the front of the trunnion to the barrel. I seated my trunnion in my receiver and welded it up, then welded over the pin holes. Now I realize that the pin location is off. I'm not 100% sure how to approach this. I figure I am going to have a very tough time drilling through the pin/s but I can't see any other option. I also figure it is going to be tough for me to even find exactly where to drill. Any help here would be great, I don't want to have to scrap this build, and I'd also prefer not to have to get a new barrel/trunnion.

HELP

[rustypirate]

I hate to say it, and I hope I am wrong, but it looks like you hosed yourself on this one.

you could try to grind out the welds where the pin holes are and drill out or press out the barrel pin, but you may have issues there too.

drilling may be your only option, just drill undersize and see if it loosens up.

[cimmaronkid]

Did you used to work for Century when they built the Cetmes? (:roflmao: )

Have you checked your bolt gap? If it is good to go range (above .005"to max .020") then I would continue on with the build. + size rollers will make up for wear and it is doubtful that you would ever shoot out the barrel, especially using NATO pressure rounds.

If it ISN'T within spec, bet out the Dremel and cut the weld at the front of the trunion on the barrel (don't do that again, please) and drill out the welds on the receiver and remove the bareled trunion. Get a tungsten carbide drill just slightly larger than the barrel pin you welded over and drill them out. use a slow speed with cutting oil and keep the drill cool. Then fabricate a new pin the size of the drill, rotate the barrel 180 degrees, and drill a new spot on the barrel for the barrel pin after you have welded the trunion in the receiver, pushed in the barrel and got the bolt gap correct first before installing the pin.

If you can't get the pins drilled out, then take the barreled trunion and the Dremel tool and cut the old trunion off. Just make sure you got a replacement before you do this. Contact Jorge as he might have new trunions which would be even better. Then assemble correctly.

You sure you weren't a Century gunsmith in a former life?:eek: (Just kidding)

[pjm204]

I guess I had to expect a few kicks in the ass. I'm usually better than this but I just did a hurried job and it seemed to snowball quickly. I'm hoping I can drill the pin out, I figure if I can't drill it, I might be able to take it to a machine shop and have them drill it, I knew welding the front was a horrible idea but that seems like the easiest thing to correct at this point.

[drine]

I was rebarreling mine and could not get the pin out. After two days of banging on it I decided to drill it out and used a cobalt bit. I got away with using my hand drill and never cut out. Once I got passed the pressure point which is the smack in the middle of the barrel I got a drift punch out and popped it right out. David

[pjm204]

thanks for the encouragement, I just needed some hope that I can drill this thing out, guess I need to head to the hardware store and get some bits

[pjm204]

who is jorge and how do i contact him about the trunnion in case I need it?

[okie shooter]

who is jorge and how do i contact him about the trunnion in case I need it?
Jorge, is "arnaiz", a member of the board here.

[okie shooter]

On getting the pin/pins out, if you know any machine shop with an edm you might get some one to burn it out, if you can find the pins well enough.

[pjm204]

I just bought a bunch of cobalt bits so my plan of attack for my HUGE mistake is to use an endmill to open up the welds covering the holes, once I clear both sides and can access the pin, I will attampt to step drill it. hopefully all goes well.

[Big Steve]

That's going to be the hard part. Finding the outline of the pin so you know where to drill. Do you know any one with a mill? If I were attempting it I would slowly mill down with like a 1/4 in mill and keep looking for the pin out line. A little heat may make it show once you are down to it. If all else fails you can probably salvage the receiver and the barrel once you get it out of the receiver. Even if you have to Ziz wheel the trunion on both sides and split it off the barrel.
Steve

[pjm204]

Yea I'm going to try and salvage everything of course, but I think at the very least I can keep the barrel and receiver, and I know that I can make it all look nice and function well once I get through all this crap.

[pjm204]

well I used a mill to uncover the pin and I gave it a few whacks to see if it would budge and what do you know, it moved ever so slightly. I've had a bit of trouble setting it up on the press. I think tonight I am going to try and hammer it out. I'm starting to see the light at the end of the tunnel.

[cimmaronkid]

.... I'm starting to see the light at the end of the tunnel.

Just make sure it isn't the freight train headed at you! :wow: Hope everything works out on the rebuild.

[pjm204]

haha, glad to see you've got faith in me. if it can be done by me, it will be done tonight.

[pjm204]

The answer to this thread, no I am no longer screwed, I drilled the pin out and will have the barrel pressed in no time. The pin drilled extremely easily with cobalt bits, I'm talking less than 5 mins to drill it out.

[arnaiz]

who is jorge and how do i contact him about the trunnion in case I need it?


No trunions , sorry.

[pjm204]

no problem jorge, I'm not in need of a trunnion, but thanks

[Seattlefungus]

PTR91 carries trunions for $55... I know they work on G3's I don't know if they work on CETME's

[M1 Tanker]

PTR91 carries trunions for $55... I know they work on G3's I don't know if they work on CETME's

You CANNOT use a G3 Trunnion on a Cetme. The trunnion, bolt, locking piece, carrier are not interchangeable between the two.

[rustypirate]

If you wind up needing a CETME trunion, I have one in a receiver stub that I can part with, but it sounds ike you have repairs well in hand.

[pjm204]

thanks rusty, I think I've got it covered but it's good to know it's there if I need it. I don't want to have to removed mine though because its welded in there really well

[Grasshopper]

Will there be a heat treating issue here? Is he OK?

[pjm204]

I'm not worried about it. But if I should be, let me know. I think it will be plenty strong. I did manage to get the barrel out today, once it popped, it came out nicely, I made one of the tools that perro showed in another post, worked well. Looks like I'm back in business!