New upper

[socalT]

Assembled my new Saber Defense Upper to my just built lower, took her to the range and Click!! Nada ...Pulled back on the charging handle extracted one round, loaded another and fired with no extraction. Bolt, charging handle comletely froze tight. Had to use corner of table against charging handle to get loose. Any help for a FNG would be much appreciated...... Repeated this three times and gave up

Saber M4 Tactical
Magpul CTR
Kaiser Loswer

[CHS]

Did you function-check the lower after assembly?
Did you lube everything properly?
Is the gas tube installed? Is it installed properly?
Is the buffer/tube/spring installed correctly?
Is the firing pin retained properly?

Pics?

[CHS]

Also, what ammo were you using? Did you strip and clean and lube the rifle before you ever fired it?

[damon1272]

As I read your post, I take it the upper was a factory assembled unit that has been untouched? or did you assemble the the gas block/ front sight assembly?

[socalT]

yes factory assembled upper, cleaned, lubed.. although one guy at the range thought it was pretty"dry". came home and cylcling both the original culprit mfg relod ammo and some wolf i had at home. Same thing.

[fusionstar]

Hmm

Are you sure your BCG is completely and correctly assembled? If your yanking back on the CH and the lugs just wont turn without a huge amount of force the it could be your cam system, your bolt should come out with a flick of the wrist and unlock with little effort.

Does it chamber smoothly? Does it go into full battery when bolt release is pressed and the BCG flys home?

It could be that something is just out of spec or installed incorrectly.

However, I cant think of a reason why a ar that chambers a round fine is not unlocking even when the CH is yanked.

Make sure your BCG is not being blocked by something like a bur in the buffer tube or the lower itself.

[Blue]

Something similar to this happend with my buddies gun, he didn't put the buffer tube on right and the buffer detent thing got all mixed up in the gun and jammed it all up. Have you split the upper from the lower again yet?

[NorCal MedTac]

Did the ejected round have evidence of a trike at all on it? Ensure that your hammer spring is in right. Did you put in some crap like an accuwedge in to "keep it tight"?

[alexander]

Something similar to this happend with my buddies gun, he didn't put the buffer tube on right and the buffer detent thing got all mixed up in the gun and jammed it all up.

Double check this. I got excited and reassembled a gun without the spring/buffer; it was obvious something was wrong when I pulled the charging handle. : |

[socalT]

update,

Field stripped/cleaned and lubed all day Sunday. Back to the range yesterday and it worked like a champ for the first 75 rounds then started the original problem all over again.

An added feature that when I cleared the FTE/FTF the next round would not fire. Only would work if I let the bolt close using the bolt release.
Questions?
If it worked for the 75 rounds, is it a "need more lube/more cleaning"
Does it break in over time?

Any help would be appreciated
Thanks

[socalT]

Did the ejected round have evidence of a trike at all on it? Ensure that your hammer spring is in right. Did you put in some crap like an accuwedge in to "keep it tight"?

My first build, I think the spring is in correct.
No Accuwedge

With rifle broke open l noticed quite a bit of brass shavings, normal?

[alexander]

With rifle broke open l noticed quite a bit of brass shavings, normal?

Not that I've seen in my builds. How's your mag catch, is the magazine tight with the bolt pulled back? I had an FTF when my bullet button started coming loose.

[socalT]

bullet mag nice and tight...mags fit good ..using 10rd c products..any known issuses with those mags