180-B problem - final update

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Mr. Spectacular

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- In before ArmedSask tells me to "read the #$*%#&*$ FAQ"

- Also in before someone tells me to "clean my gun". :rolleyes:

- Also in before someone says "try different mags".



I noticed last month that my 180-B wasn't locking back on the last round on some PMAGS. I wrote it off as a PMAG issue and carried on even though this was a new condition that I've never experienced in ~1 year of shooting this gun using the same magazines.

When I shot it two weeks ago, I noticed that some of my previously "known good" PMAGS had started to also not lock back the last round.

This weekend, my 180-B refused to lock back on any magazine I have, period (10 PMAGS and 4 LAR).

If I pull the bolt back and take my finger and insert it into the magazine well and press up on the bolt hold open "tab", the bolt will stay open until I remove my finger.

Again, to prevent some of the canned responses that some people like to give: this is NOT a magazine, nor a gun cleanliness issue. There is something broken and I'd like to fix it.

Here's what I need to know: Does this sound like a condition of a broken or weakened trigger group spring (or other type of spring), if so, what type of spring is it, and where can I find a new one?
 
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Knowing nothing about the 180b, the two firearms where I've taken apart the bolt catch (XCR and Swiss Arms) - it is obvious the bolt catch is spring loaded to move itself out of the way. The follower of the magazine overcomes that spring pressure and pushes it into place so that it stops the bolt from closing.

Knowing this.... a broken spring should mean the bolt stays open sometimes when there is still ammunition in the magazine (as there is no spring pressure forcing it out of the way).... so we can rule that out.

I would suggest that the bolt catch part itself may be bent somehow....if you holding it in place holds the bolt open but when you remove your finger it closes. The catch may be bent in such a way that it can no longer properly engage the bolt, OR part of the catch may have broken off and it no longer positively engages the bolt. Have you disassembled the gun and taken a close look at the part? Do you know anyone with a 180b you can compare the part to?
 
Check the condition of the bolt catch hook. It may be damaged. Check that the lip on the bolt catch that engages the mag follower isn't bent so that the catch doesn't raise high enough. Check that the notch on the bolt that the bolt catch grabs isn't damaged.

Finally, what PMAGS are you using? Do they have the V shaped notch in the back, or have you ground that out to work with the large bolt catch of the AR180B? If not, it's possible the mag had engaged the bolt catch enough that the bolt has damaged the catch hook.

Oh, read the ####ing FAQ!
 
Armedsask said:
Check the condition of the bolt catch hook. It may be damaged. Check that the lip on the bolt catch that engages the mag follower isn't bent so that the catch doesn't raise high enough. Check that the notch on the bolt that the bolt catch grabs isn't damaged.

Finally, what PMAGS are you using? Do they have the V shaped notch in the back, or have you ground that out to work with the large bolt catch of the AR180B? If not, it's possible the mag had engaged the bolt catch enough that the bolt has damaged the catch hook.

Oh, read the f**king FAQ!
Click to expand...

That's what I would suspect has happened. I noticed the same issue (didn't have any damage though) with my 180 and pmags.
 
Hey, it's not an AR 180B thread until Armedsask shows up and tells you to "read the ####ing FAQ!". Am I right? :)


Alright, here's some pictures:

The "tab" is bent, obviously.

dsc01717ut.jpg


dsc01718xm.jpg


dsc01719nv.jpg





There is a spot of damage on the very top of this piece, if that means anything:

dsc01721pz.jpg




I pushed down on the follower to take this shot. I haven't modified these PMAGS at all, but the "tab" doesn't seem to have any problems fitting into the slot on the PMAG.

dsc01727iz.jpg




The flat steel piece on the right hand side (our perspective in the picture) appears to be one piece and incorporates the bolt hold open "tab". Is it possible to just remove this piece entirely and forfeit any bolt hold open feature? I don't really care if my bolt stays locked to the rear after shooting, that doesn't bother me at all.

dsc01728z.jpg
 
You need to square off the notch in the back of the PMAGS so it doesn't engage the bolt catch on a full mag. The mags are pushing the bolt catch up when they shouldn't be. This has damaged your bolt catch. You might be able to bend the bolt catch tab down so it lefts high enough to grab the bolt. First you need to fix your mags. The mag body should not lift the catch AT ALL.

Remember how you said you read the FAQ? This issue is in there, although it is for Thermold mags. The concept is the same. New style EMAGS don't have this problem.
 
Armedsask said:
You need to square off the notch in the back of the PMAGS so it doesn't engage the bolt catch on a full mag. The mags are pushing the bolt catch up when they shouldn't be. This has damaged your bolt catch. You might be able to bend the bolt catch tab down so it lefts high enough to grab the bolt. First you need to fix your mags. The mag body should not lift the catch AT ALL.

Remember how you said you read the FAQ? This issue is in there, although it is for Thermold mags. The concept is the same. New style EMAGS don't have this problem.
Click to expand...

Yep, you're right. The catch doesn't go all the way down, it sits in the V-notch of the Pmag about 5mm from actually touching the bottom.

Okay, so we've determined that I can bend the tab back and adjust the PMAGs.

What I'd like to know is what about if I just remove the entire bolt catch lever and forgo it's operation entirely? Have you ever tried that before?
 
What a ####ing #### show this is turning into.

So I took the whole entire bolt catch assembly off the gun. The latch itself, the plug that fits inside the receiver and the spring.

I will confirm that the safety does not need any of the above to function as it was intended. The spring for the bolt catch just sits on top of the safety selector in a little grove, it doesn't impede it's ability to work as designed, as far as I can tell.

The gun appears to work with all of that missing, but the bolt hits the magazine follower so hard that it actually dents it, and I only did it a few times. This is obviously not a long term solution.

So I go looking for a long-term solution (without having to perfrom retroactive surgery on my PMAGS). I go to Questar and look at EMAGS. ####ing great, the have them, they're almost twice as much as a regular 5 round PMAG and they require "customer filling", whatever the #### that means.

So I'm going to pay you twice the original price for a product that you're going to send me that I have to file and fiddle-#### with once it gets here? LOL. PASS.

Here's what I'd like to know: Is the rear notch the only "modification" I need to make to my PMAGS to make them 100% AR-180B compatible?

(A side note to the above question - I went and searched for "difference between EMAG and PMAG" on Google. Apparantly the EMAG is STANAG compliant. I'm thinking great, I have an answer that is starting to make sense. Than I read the the ####ing PMAG is also STANAG compliant. So what the hell? What good is this stupid "STANAG" qualification to begin with?)
 
Armed, I need you help here, man.

I cut two of my PMAGS down on the rear notch so that the bolt catch sits inside of them perfectly, and the bolt catch feature still isn't working.

It's almost like either the PMAG spring has too little pressure pushing up, or the bolt catch spring has too much pressure pushing down to where either or will engage the mag follower just enough to let the bolt go into battery.

This isn't nearly a big deal as I really don't care if I have a last round hold open or not, it just pisses me off that it's supposed to be there and it doesn't work and I don't know why.

Anybody have any ideas. I got nothing. :yingyang:
 
In one of the photos there is a circled catch lever or whatever it is. I had similar wear on mine, though it would always lock back. I filed mine a bit to smooth it out and it still works fine. However I don't have any P-mags. If you look near the end of the Ar-180 FAQs thread I put up a couple photos of what I had happen.

Probably doesn't help you any but having reviewed my photos I have similar damage on what I call the bolt catch. It holds the bolt open on the last shot and the tab by the mag is what actuates it.
 
Try some regular steel mags and see if your bolt catch tab needs to be bent down. Eliminate the PMAGS from the equation for now.

If you're really having troubles, you can send me the rifle and I'll fix it. If all else fails I can put in a new bolt catch lever.
 
I have a similar problem… when I first got the rifle and pmags the bolt catch didn’t work with them… last time I had the rifle out it would randomly lock back on the last round and sometimes release on its own… if I try the finger in the magwell and push up the bolt catch it barely holds the bolt… a good jolt and the bolt will drop… inspecting my bolt catch carefully I can see that the hook appears to be bent to the side… your pictures look very similar to my beat up bolt catch, looks slightly bent the same too… I now believe that using the pmags has caused my bolt carrier to smack my bolt catch and slightly deform it causing a very similar issue to what you describe…

Well… I got to say you guys helped my figure out what was going on with my AR180… now I have to figure out a fix or get a new bolt catch… hope this helps and you get it figured out…
 
At least the xcr doesn't use a plastic lower that breaks when you open it too far.

Spec'ing a sub-par material for a lower is definitely a user error though right?
 
Armalite doesn't go around telling the world they have the world's most superior combat rifle. A rifle that will rule the world! They also don't send angry letters to people with warranty issues.

It is what it is. At least AR180B users aren't delusional about what they have.
 
-Update-

I went over to a friends house who has EMAGS that he uses in his Tavor and tried one out. It's basically just a little slimmer and the "v-notch" in the rear of the EMAG is pretty well exactly the same as a regular PMAG (from what I could tell).

Thanks for the offer, AS, but I'm just going to leave it as it is. Like I said, I don't really care if it has a last round hold open or not. My 3 10/22's don't have it and I'm used to it now.

I did straiten out the tab in my vice so that it sits flush with the follower and ground it down a bit so that it fits inside of regular PMAGS better. Considering that this isn't really a safety issue, I'm just going to leave it as-is and shoot the hell out of it.
 
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