Not a good day at the range with new upper.

[t44e6]

Slapped a mag in, bopped the bolt release, pull trigger, nothing. Bolt didn't go into battery as it is headspaced short. Fun ahoy.

[e292644]

I'm sorry to hear that. What type of ammo did you use? I use steel case on my first shot and it stuck in the chamber so tight had to knock it out with cleaning rod.

[Arkane]

The headpacing is tight on them when they are new, that's for sure. On my second one I chucked a 5.56 chamber brush and rod section into my drill and cleaned the snot out of it before hand, That seemed to do the trick.

[t44e6]

I was shooting MEN M193, German brass cased stuff. I messaged Wolf, I will see what they say. It definitely would not close on a Go gauge.

[Arkane]

I was shooting MEN M193, German brass cased stuff. I messaged Wolf, I will see what they say. It definitely would not close on a Go gauge.

OK, stupid question but having seen it before: did you completely clean the chamber and locking lug area and remove both the ejector and extractor from the bolt before checking it with the GO Gauge?

[t44e6]

Yes, I have a generic bare bolt that I use.

[t44e6]

I am going to clean / polish the chamber and do some testing with dummy rounds before I venture out again.

[e292644]

I second that, give the chamber a deep clean and lube it with good lubricant.

The headpacing is tight on them when they are new, that's for sure. On my second one I chucked a 5.56 chamber brush and rod section into my drill and cleaned the snot out of it before hand, That seemed to do the trick.

[Arkane]

I am going to clean / polish the chamber and do some testing with dummy rounds before I venture out again.

I've kept an eye on forums and people's experiences and between that and what I've encountered with my A1s it seems like the nitriding in the chamber is kind of thick, and likely has some residue left over from the manufacturing process. Like I said, I chucked a 5.56 chamber brush up in a drill, soaked the chamber with CLP and went to town for a while, I noticed after a good flushing and further cleaning it would close pretty well on the magpul dummy rounds. Once on the range I hammer the piss out of them for about six mags trying to get them to fail. No dice, they run like clocks.

I also recommend upgrading the extractor spring and inserts. The Wolf ones seemed kind of junky to me so I swapped in the BCM upgrade kit, but that's kind of SOP for me on all the AR pattern rifles I own.

[t44e6]

I am definitely going to upgrade the bolt guts, and will probably run a Adams BCG at some point or at least a nice high quality bolt. I have a few in the parts bin.

[Jiro]

I have two of these and both did the same thing.
Both were single shots for about 20-30 rounds then worked fine.

[t44e6]

As for the nitriding being thick I don't see how that could be a thing. Nitriding is a surface conversion where a bath in molten salts changes the structure of the metal. Nothing is deposited on the surface as with plating.

[Qwerty]

Sorry to hear your issues. I went to the range with my A1 upper this weekend also. It was the 2nd time out. 1st time was all stock. I cleaned the chamber with brush prior to going both times. I've replaced the extractor spring and added an o-ring to the bolt and put in an H2 carbine buffer to the lower for the 2nd trip. Did not have any issues on both trips.