Greetings...
I am new to this board and am excited to see so much chatter about the MG34..
I have just completed a reweld semi build and am having some difficulties that I need to troubleshoot.
Hopefully some of you can educate me and lead me to the promised land.
What is happening:
I have not taken this gal to the range yet so I am in the fitting stage.
When I draw the well lubed bolt back under pressure of the spring and release to allow bolt to assume the semi auto closed bolt position, the rotating face of the bolt will initially resist going all the way into battery (comes just short of a full engagement with cams/barrel) .. After a few attempts it will and I can dry fire successfully. Only problem is it takes a momentous pull and often several tries to retract the bolt back to recharge it. The bolt will move slightly and the recouperator pops pushing barrel forward when I pull back on the handle but to take it all the way back to the rear is tough !! Its hanging up on the cams? or something?? When I watch You Tube videos I notice the pull on the charging handle on functioning weapons seems easy.
Bolt has been heavily lubed, dissassebled and seems to be working fine..
So before I bend the recharging handle or dislocate my shoulder I figured .. ASK The Experts ..
What should my coarse of action be here ??
Thanks in advance for any and all suggestions
Bill
PS.. Comments.. Bolt goes through the reciever smooth as silk and seems to function as intended when inspected by hand.. Cams are worn pretty significantly and I am replacing but could that be the problem??
Bolt retraction issues on Semi build
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42rocker
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Re: Bolt retraction issues on Semi build
All I can do is say Welcome to the site and try to send you in the right direction. tomcatshaas is in Minnesota, Twin cities area and had a mg34 and did a lot of great threads on it. He slowed down lately in his posts but does drop by. Try to pm him or email him and talk to him if possible. Another person in the Twin Cities area is DA who holds a machine gun shoot next to Red Wing. There are several folks that could help here in Fla, but it's a long drive for that. I know as I've driven from here to International Falls, Minn several times.
Later 42rocker
Later 42rocker
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42rocker
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- Location: Florida
Re: Bolt retraction issues on Semi build
Also try Jbaum of German Manuals as he knows a lot about them also and has the manuals for them.
Later 42rocker
Later 42rocker
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Cannonman2
Re: Bolt retraction issues on Semi build
Thanks guys,
I will check those leads out.. Red Wing shoot is one I have yet to attend.
Thanks again
Bill
I will check those leads out.. Red Wing shoot is one I have yet to attend.
Thanks again
Bill
Re: Bolt retraction issues on Semi build
Bill, take your support off the receiver and the bolt out, drop your barrel into the barrel shroud with a sized unprimed case on the bolt face and make sure you can insert and rotate the bolt so as the roller passes the bolt stop, if it won't, take the case out and try it with o Ly the bolt.it maybe binding up in there somehow.
V/R
Crash
V/R
Crash
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Cannonman2
Re: Bolt retraction issues on Semi build
Thanks guys.. Crash, I PM'd you with questions..
Something else came to mind. When I remove bolt and carrier and lube them up and manually cock it and work the carrier there is a slight catch where sear comes in contact with the shelf with the small notch in it (Right by the reatainer clip or ring that holds the firing pin in).. You can see the sear catch and then release (just a slight catch that is overcome with a little pressure). When the end piece that screw on the end of the firing pin is put on and tab is turned down, the bolt and carrier are stiff and not as fluid as others I have seen. Slanted slot in the carrier is a bit sloppy for the lug on the bolt and one would think that would make it more loose but it is not.
Question I posed to Crash but will pose here also is whether removing metal just at the edge where the bolt jumps onto the ledge of the carrier (or visa versa) would be prudent.. This is where the diffuculty happens.. just as the bolt and carrier are making that transition and just as the bolt is reaching the very end of the cams to pull straight.
BTW.. I replaced my cams with like new ones but it has not made a difference.
Hope I have described things well enough..
Thanks
Bill
Something else came to mind. When I remove bolt and carrier and lube them up and manually cock it and work the carrier there is a slight catch where sear comes in contact with the shelf with the small notch in it (Right by the reatainer clip or ring that holds the firing pin in).. You can see the sear catch and then release (just a slight catch that is overcome with a little pressure). When the end piece that screw on the end of the firing pin is put on and tab is turned down, the bolt and carrier are stiff and not as fluid as others I have seen. Slanted slot in the carrier is a bit sloppy for the lug on the bolt and one would think that would make it more loose but it is not.
Question I posed to Crash but will pose here also is whether removing metal just at the edge where the bolt jumps onto the ledge of the carrier (or visa versa) would be prudent.. This is where the diffuculty happens.. just as the bolt and carrier are making that transition and just as the bolt is reaching the very end of the cams to pull straight.
BTW.. I replaced my cams with like new ones but it has not made a difference.
Hope I have described things well enough..
Thanks
Bill
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Cannonman2
Re: Bolt retraction issues on Semi build
A followup to my bolt retraction issues..
Did a combination of several things.. Changed out barrel for a different one, replaced TNW spring with the original auto spring, replaced cams with like new and it seems to have solved issue.. Bolt now retracts after firing with little effort and I am going to go out and spend some range time and see if it behaves like I think it will.
Did a combination of several things.. Changed out barrel for a different one, replaced TNW spring with the original auto spring, replaced cams with like new and it seems to have solved issue.. Bolt now retracts after firing with little effort and I am going to go out and spend some range time and see if it behaves like I think it will.