CETME sporter 308...

[brian923]

my cetme sporter in 308 is not shooting right. well, now that it was "fixed". i had a case split in the chamber, and when i couldnt get it out on my own with the cleaning rod, i took it to a gunsmith. when i got it back, it doees this...

it will shoot two rounds, and then jams the next. i clear the chamber, and then two pops, and a jam. does this with both new, and old mags. any suggestions?


i took it back to the said gunsmith, and he says that its because its a cetme and that he wont do anything about it, without charging me a hefty fee to figure it out. i think that he messed something up, and dosnt wasnt to say anything. now i am not really liked at that gunstore, and i did nothing wrong.

i just dont know what to do?

 

[W.E.G.]

You aren't providing much information when you just say "two pops and a jam."

We can't read your mind.

MORE DETAIL!!!

 

[brian923]

sorry, .......i thought i did an okay job....but.... it shoots two rounds and then jams. i then have to clear the chamber buy manually cycleing the action to load another round. the round that comes out is damaged. then it will shoot 2 more rounds and then jam..(two pops and a jam) does this through the whole mag. the bolt seems to ride on top of the cartridge which scores it. i have tried new mags, and the old mags that came with the rifle when i bought it. i dont know what the gunsmith could have done when he removed the broken shell, that would have made this happen. as i said, it shot perfectly before the broken shell.

 

[nalioth]

Cetmes and HKs are different in many many ways.

This is a military surplus rifle, designed for 7.62x51 Nato. The chambers are fluted and using commercial ammunition is not advised. Nato specification ammo has thicker case walls and won't split or crack in these flutes. Make sure your chamber flutes are very clean (you can use a .45 brass brush to clean it).

If you do shoot commercial .308, I'd advise you get a broken shell extractor.

 

[86thecat]

If Nalioth's advice doesn't fix the problem go to militaryfirearm.com forums- they can help with CETME and G3 problems. I would only send a Cetme to a gunsmith that builds them, as Nalioth stated they are different and have their own quirks. Trigger pack height and mag height need to be in spec or they will become a jam-o-matic. Most problems can be solved if you get good advice.

 

[brian923]

thanks guys, keep it coming, and ill let you know how its going. brian.

 

[ocharry]

hi brian,,,,where is the cartridge damaged???? on the rim or the side or the bullet???

have you had it apart to look things over??? do you know how to take it apart???? should be four big pieces,,, but stock,,, lower receiver with the trigger pack,,,,bolt carrier with bolt face attached,, and the upper receiver with the barrel and cocking tube

push the 2 pins out that are just forward of the but stock and the rear end of the rifle will come off,,,hold onto the pistol grip so it doesn't fall off,, if it is a snug fit just bump it a little with the palm of your hand,,,,usually the y will just slide off,,and if the lower is snug just pivot it down away from the upper,,,the front end is sitting on a shelf,,,,take hold of the cocking lever and open it and pull as to cock the gun and the bolt carrier will slide out the back end of the receiver

look at the bolt face to see if the extractor is bent or messed up,,, also look at the breach face to see if there are any dents or marks

if you have one of these rifles you NEED to have a broken shell extractor in your kit,,,,extraction and ejection is a violent action in these weapons


let us know how it goes

ocharry

 

[brian923]

the damage is on the side of the round. there is no damage to the rim of the cartridge. the bolf face and the extracter are in good working action, nice and smooth, straight, and the face is nice and clean.it almost seems like the bolt is riding on top of the round, and not stripping it correctly. how far up is the round soposed to it in the area above the mag. (make sence?)

 

[ocharry]

kinda sounds like it is short cycling or the mag is not in the correct position

if you hand cycle with some dummy rounds are they coming up for the bolt to catch the rim or is the bolt riding over the end???

did the "smith" scratch the chamber when he was trying to get the casing out?

or tweak the receiver

causing a retarded extraction,, and or cycle

is the magazine coming unlatched and dropping out causing a bolt over ride

just thinking with my fingers here

is the trigger pack to high causing it to rub the bottom of the bolt carrier,,, and slowing the cycle

ejector could have gotten bent and is now riding the bolt causing a retarded cycle,, it runs in a slot in the bottom of the bolt,,,,,take the mag out and look into the bottom of the rifle while pulling the bolt back,, see if the ejector is dragging on the bolt,,,,or if it feels like something is dragging

ocharry

 

[86thecat]

Open the action untill 3/4" of the bolt still shows in the ejection port, looking into port with a good light is there 1/16 to 3/32" clearance from top of mag feed lips to bottom of cutouts in bolt head?
Does the bottom of bolt depress follower about 1/8" as it cycles through mag? Century receivers are known for long mag wells and problems locking in.
Open action until ejector is even with face of bolt (depression where case head sits) does top of ejector almost drag on bottom of groove (less than .020" clearance even when pushed down lightly)? If fired case isn't being ejected properly you could be getting a partial double feed. The ejected cases should fly 20-30 feet, yes feet, unless there is a port buffer.
Reach in and grab behind extractor with index finger, extractor should not move outward with firm pressure.
Grasp front of trigger guard, firmly try to move trigger pack up and down, should not have much play (1/16" may be too much).
Cetme/G3's may not cycle properly unless Military brass is used at mil spec pressures as the soft brass extrudes into the flutes. The chamber must be clean (scrubbed with a 45cal brass brush and cleaner) so the flutes can allow pressure to equalize around case so it will extract properly.
I believe these rifles must be thouroughly cleaned and bolt assy detail stripped as powder residue will coat everything inside the receiver, and that too much oil is better than not enough and oil all moving parts (not chamber or bolt face) and inside of receiver with Mobile1.