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spudwrench777
11-19-2011, 12:06 PM
thanks for allowing me into this great forum. i'm new to the battlrifle game. i have always wanted one, anyone chambered in .308 only. i fell in love with this cetme when i saw it on display at a friends pawn shop. should have done my homework. it had zero gap and had been shoot a considerable amount. the locking piece is hitting the back side of the bolt firing pin hole. one roller measures 2 thou undersize the other a half thou under. deep divits on the locking piece ramp. the tube end on the bolt carrier is nice and peened. the bolt itself measures 1.839" oal. guess this things been pretty shot out. i've built many 1911's and pump guns, but this is my first attempt at a battle rifle. i've ordered a milsurp bolt assembly, locking piece and standard rollers from apex. any suggestions out there for a newby? oh yea, its a century with the old cast stainless receiver. thanks guys.

gtty
11-19-2011, 01:04 PM
Welcome to the forum!! I have built two CETMEs and love the rifle also. The good news is your rifle can be brought to spec by reading here. There are lots of really helpful folks here. Holescreek I would have to say is the ultimate expert. Read some of his (and others) stickies and you too can be an expert.

My first build shoots great, but my second build has lost its bolt gap so I'll have to re-press the barrel. (not quite sure where I went wrong there).

Once again, Welcome

holescreek
11-19-2011, 05:39 PM
I'm more like a beginner to intermediate cetme builder but I like to measure stuff. You are on the right track in replacing the carrier, rollers and locking piece. Your bolt head sounds long by cetme standards but the extra .005" could be your measuring instrument. Replace the parts, recheck the gap and see where it's at. I have no experience with the cast receivers or their issues, hopefully you get your gap back where it belongs and it won't matter.

spudwrench777
11-20-2011, 07:29 AM
I have found that it is hard to find an exact over all length for the bolt head. of course I may not have gone to the right web sight yet. I keep my calipers checked with go blocks, so I know they are within a half thou. I also have them calibrated once a year where I work. It appears I hve 2 problems to work through. Bolt gap and cocking tube gap. Bolt gap, short of replacing the trunion, appears to be an easy fix. the tube gap I havn't been able to grasp in my head fully yet. Must have to do with getting old. Based on all that i have read on this sight, you guys have all the answers. I contacted a few friends back home who are small arms experts, even they say its a crapshoot with a century CETME. They are retired 5th group Special Forces who set up firearm buisnesses in my hometown of Fayetteville, N.C. I trust that with this websight and these three friends i can end up with a really nice shooter instead of a high dollar paper weight. All i'm doing now is waiting on my parts and getting antsy to go shoot this beautifull piece of history. Would any of you gone with the milsurp parts or ordered new manufactured bolt, locking piece, and carrier. I didn't want to sink a ton in her untill I found out if the trunion is bad. Again, thanks for all the help.

rpmfly2
11-20-2011, 09:10 AM
The only issue with the cast receiver I have is that the HK Claw Scope mount didn't reach around the receiver. Some people file the mount claw and some like myself when I built the rifle cleaned up the SS receiver. The stainless is very hard and ridgid! Stainless can be hard to work and don't get sandings or the dust in your eyes! It will hurt like heck till your tears float it out! My stainless shoots tighter groups than my sheet metal receivers do and I think it is the receiver being stiff. I did a test with the same scope on all 4 builds and it doesn't flex as much.

bladeworks123
11-20-2011, 04:04 PM
I have found that it is hard to find an exact over all length for the bolt head. of course I may not have gone to the right web sight yet. I keep my calipers checked with go blocks, so I know they are within a half thou. I also have them calibrated once a year where I work. It appears I hve 2 problems to work through. Bolt gap and cocking tube gap. Bolt gap, short of replacing the trunion, appears to be an easy fix. the tube gap I havn't been able to grasp in my head fully yet. Must have to do with getting old. Based on all that i have read on this sight, you guys have all the answers. I contacted a few friends back home who are small arms experts, even they say its a crapshoot with a century CETME. They are retired 5th group Special Forces who set up firearm buisnesses in my hometown of Fayetteville, N.C. I trust that with this websight and these three friends i can end up with a really nice shooter instead of a high dollar paper weight. All i'm doing now is waiting on my parts and getting antsy to go shoot this beautifull piece of history. Would any of you gone with the milsurp parts or ordered new manufactured bolt, locking piece, and carrier. I didn't want to sink a ton in her untill I found out if the trunion is bad. Again, thanks for all the help.



1.839" on your bolt head is on the high end of good as far as that goes. 1.837" is pretty much average for unissued bolt heads even. Your roller windows should measure out .317" to .319" and you should be at .595" from the face of the bolt head to the leading window edge.

30016

spudwrench777
11-26-2011, 04:54 AM
thanks for the pictures and measurements. they are very helpfull. i received my parts from apex on black friday. my new bolt measures 1.834" a 5 thou dif. seeing as how i have the thicker cast receiver, should my bolt carrier slide out of the receiver freely when i turn it muzzle up? as it is now it remains where ever i push it to. i have also been reading and rereading bladeworks piece on cocking tube gap. i know i'm rambling but its been a long day. ct gap is my next step after bolt gap is set? i know i'm ready to put this thing together and see what i have. just want to make sure i'm stepping in the right direction. i'm concerned about the carrier sliding freely and ct gap. it seems this rifle was pretty much used up. if i have to end up repressing the barrel, who is the best at it and how much should it cost? hope to assemble her when i get off of work today. only thing is my daughters 1911 extractor broke so i have to fit a new one for her first before i start on my pet. thanks and again , sorry for the rambling, must be getting old or something.

Perro Del Diablo
11-26-2011, 09:04 AM
bolt group should stay locked in the trunnion when you go muzzle up - if it falls freely out of the trunnion without unlocking it from the trunnion with the cocking handle then you have problems. once unlocked from the trunnion though it should fall freely out the back of the receiver.

I know several local gun stores who refuse to buy ANY Century made HK or CETME product because the odds of getting a bad one are to great. That is a shame too, because when built properly, these are some of the nicest shooting 308s out there.

The biggest issues with the cast receivers from back in the day (before they ever even introduced a stamped sheet metal receiver) is that the casting needs cleaned up in the trigger pack area and it wasnt always done correctly, and the hole for the magazine release button was machined in a different spot on almost every single gun that they released. Some fit cetme mags perfectly, some fit HK mags perfectly, some fit both perfectly, and some fit NONE perfectly. Some allowed the use of thermold mags, some you couldnt get to seat into the magwell because the catch hole was off too much. Part of the troubleshooting back in the day was to remove the entire mag catch assembly and then insert the mag into the magwell to see how far off the machining was for the square mag catch hole.
there was also a bad problem with the underside lugs for the trigger pack, and the the shelf area of the magwell. Some people couldnt get the trigger pack to seat cause the underside lugs were never machined after the casting, where on the other side, the magwell shelf was so small that the grip frame would droop in front and not allow proper ejection so a shim needed to be made to raise the front of the trigger pack up.

they also never grasped cocking tube gap and there were issues with cracked welds because they didnt know how to weld a cocking tube on - they finally figured this out by enough complaining from our group so they started to grind the ends of the bolt carrier tube and then came the hard to cock problems.

the receiver is oversized as mentioned by rpmfly2 so claw mounts didnt work correctly out of the box - this is a tricky problem and most people feel the need to reduce the sides of the receiver under the lugs, but the real problem is with the scope bridge. It sits too tall for the claw mount, and a small amount of material removal in that area is all that is needed to fit a claw mount properly without needing to file the pads of the mount or the sides of the reciever.


who is the best at repressing a cetme barrel? There are not a whole bunch of people dumb enough to take on that liability which is why its not a service offered up as much as say barreling, and headspacing a FAL, or changing a barrel on an AR15. With all the added problems from the Century Arms built guns, most smiths refuse to touch anything made by Century with good reason. They have no problems working on the FMP barreled guns, or the springfield armory EBO guns, and definately not the MARS CETME or HK built guns, but start talking about Toad Bailey built HKs, or CAI built CETMEs and most smiths run screaming - too much liability and i don't blame them.


my experiances - your mileage may vary

spudwrench777
11-26-2011, 11:14 AM
i should have clarified about the bolt carrier sliding freely. i stripped all the bolt assembly out of the receiver, and slid the carrier only back in and then turned it muzzle up. the carrier stayed where i put it. you don't have to force it or anything, it's what a machinist would call a slip fit. moves freely but won't fall out. this rifle has been shoot a considerable amount, judging from the amount of fouling buildup and shiney slick surfaces at the rear of the barrel, bolt face,bolt rear, etc. i can only base this on my work with shoot out 1911's and pump guns i've repaired over the years.

spudwrench777
11-30-2011, 03:54 PM
got it back together now. i have .009" bolt gap. should i use +4 rollers? to get to .014
thou.? i've done the HK slap and pulled the trigger now 12 or 13 times. the gap stays the same. my only concern is that the ct gap is still at around .005". i dressed the end of the carrier tube but did not shorten it. can i shorten it to get the required .015" above bolt gap?

cem308
12-02-2011, 10:20 AM
Sounds like you have some work cut out for you but its fun and you will learn alot.This forum is great and everyone helpful,wouldt have got mine squared away if not for this site.