any ar experts out there? bolt wont stay open with empty mag inserted

Ar you saying that the magazine won't push the bolt stop up, or that on the last shot the bolt isn't staying open? Could be several things, need more info.
 
+1....try a different magazine
Sure not an expert but actually did stay at the Holiday Inn Express in Austin last night.
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Jimmie, Sorry, I must have missed the first post when I skimmed through the "Actives"...

If your mag is not fully seated in the latching position, it will allow it to sit just far enough down that the follower will not trip the bolt lock... I have a couple of mags that have to be really slapped to seat them and they fit the mag well tight..They feed good, so I haven't replaced them..

You might take a look at the bolt lock catch to see if it is protruding far enough to be caught by the mag follower..It may be worn or broken off/chipped... not likely but possible..If you only have one magazine, check the follower to insure that it's not damaged as well..

I'm fortunate to have a bunch of magazines to swap out to if it is the magazine itself....I had a similar problem with one of the 5-round poly mags that I got from Brownell's and they were really nice about the refund...

Personally, I like the magazine followers that are metal, rather than the plastic ones, even though the plastic ones seem to be smoother and may be just as tough..it's just one thing less likely to go wrong in a pinch...
 
i tried usgi+magpul mags. the upper is a rockriver....lower is a stag and it has the adjust. stock. i have not shot it yet but it wont stay open with the mag inserted. i tried to hold down the bolt release lever to force it to stay open to no avail.
i also checked visually to make sure i can see the spring in the bolt release lever and it is there.....but i do not feel any "give" or tension. i did not take out the rollpin to check the detent.
so far im clueless.......the bolt simply rolls right over the empty mag. it is definately not the mag.
could it be that the bolt is short stroking?? or maybe a mis-match of stocktube?
 
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You should be able to look down through the ejection port and watch the "block" on the bolt release lever engage the bolt on the 2 bottom locking lugs.
If you pull the charging handle full back, there should be about 1/4" of clearence between the lock block and the bolt lugs.

What are you seeing?
 
Originally Posted By: jimmiei also checked visually to make sure i can see the spring in the bolt release lever and it is there.....


but i do not feel any "give" or tension. i did not take out the rollpin to check the detent.



Well if you really can see the *spring* for the bolt catch something is wrong. The spring should be installed down in the hole and the detent is on top of the spring. There is no way you could see that spring if it's installed correctly.

In fact, I just looked at 3 AR's and there isn't even enough room under the bolt catch to see the detent, let alone the spring.

And if you can't manually push the bottom of the bolt catch and at least make it move there is something way wrong. You should be able to push it and the spring/detent should push it back.

Afraid there is something wrong under the bolt catch in the hole or the way the spring is installed..
 
it looks like i may have to take the rollpin out of the mag release and chk it out. i think it is a 1/16 punch? when i inspected the mag button i really couldnt tell if i was seeing a detent or a spring......i saw a stainless piece of something but just the very end of it, barely, so i assume something is in there. maybe it was put in but done so in the wrong way.
im not sure why the guy i bought it from would have messed with it if thats th issue here.
could he have put a diff. stock on the gun and affected the stroke distance? am i shortstroking?
 
well it seems all is ok here......im thinking about taking out the rollpin in the bolt release an go from there....otherwise i may need the help of a smithy.
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It's coming up far enough to lock the bolt. Now close the action and see if you can get the bolt back past the catch point (plus a little) by using the charging handle.

I just built the same lower, nice choice.
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Considering that the bolt release in not spec and an after market, I'll almost bet that whoever installed it fouled up something in the installation...or it may have a flaw in the production...

Those 'trigger finger' releases are nice, when they work, but I'm always skeptical about the tolerances...

If you have the original stock one, you might try re-installing it and see if the problem goes away..
 
Can you grab that follower tab and pull it up with your finger while the action's open?
Or is it frozen?

All the spring does is pull it down out of contact when the bolt force is released.
 
the mad trigger finger has been taken on and off and problem still exists. evil, i will try your suggestion. i still get no movement whatsoever from the bolt latch even with no mag inserted. ir feels like its just jammed in there with no "paddle" type movement at all. im gonna buy a punch kit tomm. and take out the rollpin and reinsert the spring and detent. thats the only thing that makes sense to me at this point. ill post some more pics of the bolt and get a better angle on the bolt latch. i know some people have issues with the mad trigger but i dont think its the cause.
 
Okay, frozen in the release position.

Looking at the face of it, where the bolt lugs contact, I don't see any indication that it's ever worked.
Mine's only got about 30 rounds through it, and I can already see skid marks where the lugs hit.

Did you buy this used? If so, the guy had to be aware, in my opinion.

Just sayin
 
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That all looks normal. I'd say the roll pin is frozen in the hole of the bolt release. I don't think it's ever worked, either. I've got less than 50 rounds through mine, and I can already see wear marks where the bolt lugs impact the stop block.

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The roll pin is 3/32", you may get it out with a 1/16" punch, but it's more likely you'll just blow the pin out first and make things tougher.

Grab a small rat-tail file, too. You're going to have to clean that hole up to clear a new roll pin before you're done, I'd bet.
 
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Do you have a rifle length buffer or rifle length spring in a collapsing stock extension tube?
Do you have a A1 fixed stock screwed on with an A2 length buttstock screw?
Does it have some sort of aftermarket "buffer pad" glued or screwed to the front of the buffer?

All these can prevent the carrier from cycling completely to the rear to allow the bolt lock to engage.
I would start here.

+++++these suggestions were given to me on another site but im not proficient enough to take it all apart to eyeball the difference.
 
Doing this was suggested at the top of page 2.

" Now close the action and see if you can get the bolt back past the catch point (plus a little) by using the charging handle."

Did you do that? Does it?

If it does NOT come back far enough, then one or more of the 3 things they asked you on the other site could be your problem.

If it DOES, then likely not one of those things.

I thought you determined the bolt catch was locked up, frozen, won't move???? Is so, THAT'S the problem. It's gotta be free and be able to move.

 


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