AMP-11 woes continue...

[Shattered]

Started sighting the gun in with the new optics and had another 5 complete blow outs with the last one melding itself to the chamber walls and only the bottom of the shell coming out of the gun. ALL the shells exhibit an expanded "belt" around the bottom of the shell... there's just too much of the 9mm shell unsupported in this design.

Time to start making a new barrel for the AMP-11.

 

[agriebel]

Wow, that's nasty.

 

[01SVTvert]

This common? Dont remember hearing a lot about this earlier. Possible the chamber is too short?

 

[Wahnsinn]

Yeah I don't recall anything about it either. You running one of the originals or the gen 2 uppers?

 

[dnh]

Have you sent it back to them yet? Mine was doing the same thing and was having the occassional OOB detonation, so it went back. No problems since then. I think they smoothed up the feed ramp(s) and shortened my firing pin a little.

 

[Shattered]

Yeah I don't recall anything about it either. You running one of the originals or the gen 2 uppers?

This was one of the original uppers. It got sent back for inspection once during the early beta tests with a similar problem. Then I sent it back a second time for all the upgrades and reported I was still having brass expansion problems. Basically, all the brass that goes into this gun turns to junk. I have several ideas that we're going to try out first before I make a new barrel.

I also discovered the extractor blew out a second time. Didn't spot that right away. Going to see if I can find it Sunday morning at the range.

This is what I got last Friday.

 

[Southern Raider]

Holy crap! I have an M11A1 upper from them I got a few months back and I am sure not having that problem! Unless you've got some funky reloads, I'd send it back once more to have the barrel examined closely.

 

[Shattered]

I'll be damned... found the extractor in about 20 minutes Sunday morning. It's fine, other than getting blasted out of the bolt head. Seems the extractor pin is the weak link here. AR's aren't usually subjected to blowouts, I guess...

 

[MAC907]

Wow, words can not describe the picutres you just put up! You definitely have a bad upper from the batch. It's doubt it's a problem with the AMP design as a whole. Mine is also a 1st Gen, but has never had any problems. I still haven't sent it in for the upgrade.

 

[Shattered]

Nobody's having any brass looking even slightly like this, then?

 

[Shattered]

Whoop... double whack...

that brings to mind... why can't we delete our own misteaks?

 

[root]

I had that but not on a AMP or a M/11

Was my M/10 in 45 acp in stock form. Swapped out the barrel and it's been G2G since.
That was about 2 years ago. There are pix of the brass on the site here somewhere.

Just let me know if you want them reposted to compare with your brass.

Like I said, barrel swap and all is good.

 

[Ulwembu]

You sure the chamber is cut deep enough? Those are headspace problems.

 

[THM7]

Holly Molly....if thats what I could expect every time I shot the thing I would develop a serious flinching problem.

 

[Wahnsinn]

Nope, my brass comes out looking as normal. Stock gen 2 upper.

 

[BPsmoke]

Is this reloaded brass? Or factory original ammo?

I used Wolf steel case in mine (both the Gen 1, and later the Gen 2 upgraded) with no problems.

I actually found the Gen 1 ran better than the Gen 2.

 

[1in9twist]

Nobody's having any brass looking even slightly like this, then?

:shocked

 

[Flame Red]

I had the first gen AMP11 and not a single issue.

Then I sent it back and got the 2nd gen modifications. It would frequently give me that OOB detention and split the cases, but never a nice bulge like that! Sent it back and they said they adjusted something. Well, they also had to replace the barrel because it bulged. Ran great after I got it back, but I only used it a couple of times.

I have not run it in several months so I hope I don't have any further issues with it.

 

[Shattered]

You sure the chamber is cut deep enough? Those are headspace problems.

Eggzactly what I thought and still do. A cartridge sits fully chambered with some 1/8 inch of casing exposed in the rear... but due to the deep barrel feed cone/guide, the bolt face is almost against the barrel. I thought I explained the problem well enough to AA, but I guess I didn't really get the point across.

 

[Shattered]

Is this reloaded brass? Or factory original ammo?

I have used both in the gun. Results are the same with the banding issue. The brass blows out easier, I would imagine with cases that have been reloaded several times. So yeah. New Federal ammo comes out belted... several times reloaded ammo doesn't come out intact what-so-ever. And yet multiple times reloaded ammo doesn't faze my MP5 or other 9mm guns.