Warning

 

Close

Confirm Action

Are you sure you wish to do this?

Confirm Cancel
Member Login

Site Notices
Posted: 2/1/2013 5:37:32 AM EDT
This is in one of my guns that was previously functioning properly.

Okay, so I have the problem somewhat isolated. It's not a magazine issue, and it's not the bolt carrier.

It seems to be the bolt catch, except for the fact that I changed that part out with a new one and the problem still persists. I also changed out the bolt catch spring and plunger.

What else could it be? I have swapped uppers, bolt carriers, etc. around to try to figure it out, but it only happens with this one particular lower and it doesn't happen when I use the upper and/or BCG with a different lower....
Link Posted: 2/1/2013 3:57:19 PM EDT
The only thing i can think of is the buffer/buffer spring maybe?It might be a weak spring not letting it go past the
bolt catch after a round is fired.Just my .02 cents.
Link Posted: 2/1/2013 4:59:03 PM EDT
It's the magazine.
Link Posted: 2/1/2013 5:33:10 PM EDT
[Last Edit: 2/1/2013 5:37:19 PM EDT by rosenbaumtravis]
Please list upper and lower specs. Mid lenght, carbine, rifle, type of stock and buffer etc. Did you pack the buffer spring with grease? When you operate the action manually, with an empty magazine, what happens? Does the bolt lock to the rear? Did you change the type of ammo you are using?
Link Posted: 2/2/2013 6:39:46 AM EDT
Originally Posted By occasionalvisitor:
It's the magazine.



Absolutely not. I ruled that out already. Any mag in the 1 gun in question, n/g. All those mags in other gun, fine.
Link Posted: 2/2/2013 6:43:34 AM EDT
Originally Posted By rosenbaumtravis:
Please list upper and lower specs. Mid lenght, carbine, rifle, type of stock and buffer etc. Did you pack the buffer spring with grease? When you operate the action manually, with an empty magazine, what happens? Does the bolt lock to the rear? Did you change the type of ammo you are using?



This happens with any upper i have on the 1 lower in question. These uppers work fine on other lowers. Lower in question is an oly that inI have had for 7 years and only recently start giving me this problem.

I only use fed xm193 but it happens when live at the range, or just with an ampty mag in my workshop.

Never packed buffer spring with grease- never heard of doing that. Why?

This happens when using with live ammo or just cycling manually by hand.
Link Posted: 2/2/2013 8:40:01 AM EDT
[Last Edit: 2/2/2013 8:46:25 AM EDT by nikdfish]
If it happens when you manually eject the last round, it pretty much would have to be one of two things, the bolt hold catch assembly or something restricting BCG travel. The bolt catch could be the cause if it is binding or is too worn to hit the follower or engage the bolt carrier. If not that, then check to see if the bolt carrier actually moves far enough back to allow the catch to rise (this is a bit more than what is needed to strip a round). If something impedes the bolt carrier movement to the rear, it would produce the same result. Remove the buffer & spring and look for trash at the back of the buffer tube that keeps the buffer from moving completely to the rear..

Nick
Link Posted: 2/2/2013 12:02:12 PM EDT
[Last Edit: 2/2/2013 8:55:26 PM EDT by Dano523]
Link Posted: 2/2/2013 5:57:10 PM EDT
Guys, I need help!

Changed the bolt catch 3 times, changed spring and plunger, changed roll pin that holds the BC.

Keeps happening. Only with this lower. Any mag, any upper, any BCG. It's the lower somehow but not the bolt catch!

WTF else could it be?

Could the hammer be pushing too hard forward on the BC? Can I file the hammer so it doesn't contact the rear of the bolt catch? Maybe the forward pressure of the hammer on the BC is preventing it from its full upward range?
Link Posted: 2/2/2013 6:07:28 PM EDT
[Last Edit: 2/2/2013 6:41:21 PM EDT by widerstehe]
UPDATE: I figured out what's happening...

The Face of the bolt is not going back far enough to get behind the bolt catch.

ETA: FIXED

Needed a carbine length spring and buffer.
Link Posted: 2/2/2013 8:48:32 PM EDT
Did you have a rifle lenght buffer in a carbine length buffer tube?
Link Posted: 2/2/2013 8:53:52 PM EDT
Link Posted: 2/2/2013 9:30:00 PM EDT
Originally Posted By rosenbaumtravis:
Did you have a rifle lenght buffer in a carbine length buffer tube?


Yep. Funny thing, everything worked just fine except the last shot bolt hold open.

Still have to test the gun though, but manually and unloaded, everything semms to function.
Link Posted: 2/2/2013 10:19:05 PM EDT
Right on... I didn't know that it would even feed with the longer buffer
Link Posted: 2/14/2013 10:35:05 PM EDT
Reviving the thread to give my experience with the same issue. To the OP, I'm glad you resolved your issue. I had the same problem with my lower. After ruling out mags, I tried three different buffers, and three different springs, in all combinations. Nothing seemed to fix it. BTW, it's a carbine, and yes all buffers and springs were for a carbine. Finally tried a different buffer tube, and that fixed it. While the exterior dimensions of both tubes were identical, the interior dimension of the first tube was shorter than the new one. Hence, it was as if there was a obstruction in the tube. Really, it was just out of spec.
Link Posted: 2/15/2013 4:54:35 AM EDT
Update:

With the carbine length spring and buffer, the bolt hold back issue went away, but I then developed an issue with feeding the rounds properly into the chamber.

Turns out, the solution was the carbine buffer with rifle spring. Crazy, but with trial and error, I got it working just fine. Shot it yesterday and it ran like a champ.
Link Posted: 2/17/2013 10:11:28 AM EDT
[Last Edit: 2/17/2013 10:13:59 AM EDT by pikie1]
What kind of buffer tube do you have? Carbine, Rifle? Mil Spec or Commercial.
Also how the hell did it work all of those years without you changing anything?
You had to do something. Makes absolutely NO sense to me!
Top Top