Check the way your extractor fits in its "socket" as the bolt closes.  You'll see what I mean once you take a look.

You might also want to check the internals of the carrier.
Are you using matching # bolt and carrier set?  I didn't and found out the carrier had a machining grove at the rear which prevented proper bolt & carrier lockup.  Replaced the carrier with a well-worn carrier from G1 and it goes bang.

Check the top of the locking shoulder. Sometimes the flat portion of the locking shoulder that the bolt carrier slides over sticks up just enough to cause a stoppage as you decribed.

Will the bolt/carier go into battery on an empty chamber?
What brand of upper receiver did you build on?

Are you sure it is headspaced correctly? Sort of sounds like the chamber may be too tight and won't let the bolt lock into battery.

What type of receiver?
What type of bolt and carrier?
What type of LS?
What type of HS gauges?
Will the bolt close when the extractor and firing pin are removed?
Does this happen with the magazine in or out?
Cocking handle installed correctly?

Other than that, look for debris in the carrier recess in the receiver. I doubt you "tweaked" or warped the receiver when barreling it, I have literally punished Imbel receivers driving the barrel home. The bolt and carrier does not have to have matching numbers, FAL bolts were not fitted say like M14 bolts. The member that found a groove cut in his BC found something done most likelyt by an armorer (or lower echelon personel) to make something work. If it was a G1 carrier, anything could have happened to it in it's long strange trip of a life.

Other than that, did you paint or finish the BC or the inside of the receiver? I have seen that cause BC lock up's too.

Lemme know

Quoted: Check the way your extractor fits in its "socket" as the bolt closes.  You'll see what I mean once you take a look.

What P806 said is ultra important. If the extractor doesn't line up with the extractor cut in the barrel, your receiver timing is off and ultimately will ruin the barrel.

We have seen this problem at ARFCOM before.

Does it stop hard or does it feel like it is gets progressively more difficult to push until it stops?


There is a possibility that the ejector block was mounted too high inside of the receiver. This would also cause the bolt carrier to stop short.

Quoted: I pulled the bolt out of the carrier and it is still hangin up at about the spot of  the LS.  So I don't think it is an extractor issue.  I colored the top of the LS with sharpie and ran the bolt carrier over it, but it didn't rub any of it off.  All I can guess is that I tweaked the receiver when I pressed the LS in. Entreprise reciever Clymer gauges STG-58 all matching kit Did not paint or finish inside of receiver .269 LS (I think it was a south african, it doesn't have the divot in it for punching it in)

It's the receiver. Entreprise receivers are often times wildly out of spec. They have had entire batches of M14 receivers that were way out. It's been a couple years since they have had a widespread dimensional problem but given the fact that you are using an Austrian parts kit, I'd point to that. Locking Shoulders do not need to be pressed in. Simply tap it with a ball peen hammer gently until the shoulder area lines up with the recess in the receiver, then use a brass drift to pond it home, no need for a press. The chance of pooching the receiver would be greater, but like I said, I doubt you used enough force to ruin the receiver. Send the receiver back to Entreprise and tell them it is out of spec, believe me, they have heard that story before. The last Entreprise receiver I saw ( a customer brought it to my gunshow table) the mag well was cut so small there was no way a mag would ever go in the mag well.

DSA receivers are pretty close to the same price (dealer price) and are made from Steyr drawings, a much better choice. I personally will only build on DSA, Imbel or Rosario receivers, other American made receivers vary too much dimensionally.

You also described an Inch LS, most metric locking shoulders have a hole bored in the center, L1A1 locking shoulders tend to be smooth with no hole. You should be able to use an inch LS in a metric receiver.

Of course, without seeing the rifle, this is all a guess. Hope this info helps.

Quoted: I cleaned it out again and rechecked with the headspace gauges.  I was mistaken and I actually have the Forester gauges, if that makes any difference. It closes with a little bit of pressure on the go, won't close no matter what on the no-go.  The more I work the action the less the problem seems to be.  If I pull back the charging handle and release it, the bolt closes completely.  If I ride the charging handle back, the carrier stops about 1/4" from completely closed.   Maybe the receiver and bolt carrier are just getting to know each other a little better?

Yes, the cocking handle could be tight, or the finish on the bolt carrier and the finish in the receiver could be a little tight and just need a little adjustment. Don't be shy, let that bolt slam home hard, it's made for that. Oil it up real good and rack the bolt back and forth with the cocking handle until it loosens up.

If you headspaced with Forester gauges, you are headspaced at 1.630" which is .308 Winchester.

I use Forester gauges as well but add two thousandths to bring the headspace to 1.632 which is NATO 7.62 minimum headspace (or very very close)

Bolt closes on a .261 pin
add .001" for extractor setback =.262
minus .002" to acheive 1.632"
you would use a .260 locking shoulder.

AK's and FAL bolts will both hang up if you don't handle them rough like the bitches they are