I have this problem rifle. The bolt catch will not get pushed up 100% unless I run USGI 30 rnd magazines. PMags and USGI 20 rnd mags do not always hit the bolt catch.
I can run only 30 rnd USGI mags, but really want to fix this troubled rifle to run most magazines.

This receiver is slightly oversize in the cutout for the bolt catch. The bad news is the company (PWA) is not longer in business and I will not get rid of this registered assault weapon in CA .
Rifle works and shoots very well, but the bolt catch issue is the final thing to make it more better.

Would a Colt 9mm bolt catch, possibly fitted to this receiver, be the answer?

Would welding up the rear flats of the bolt catch, then filing the front, hoping to move the "finger" closer to the magazine well be the answer?

Please help....................


First magazine is a PMag,  Second magazine is a USGI 20 rnd,  Third magazine is a 30 rnd USGI with Magpul follower


#1 the finger just barely missing the magazine follower
#2 finger missing the magazine follower again
#3 gap between the bolt catch (front face) is approx .0200 inch
#4 finger has plenty of room to get pushed up

The thickness and arm length varies between manufacturers. You might want to try a Colt bolt catch or a few from different vendors till you get one of the longer ones. I had a few picky lowers that I had to measure catches and swap around to get them 100% with different mags.

Numerous catches have been the same (Colt,DPMS), measuring .10 inches from the flat to the tip of the bolt catch.
Been thinking of welding the tip to increase its length, then hitting it with a file to reshape it ––-leaving it slightly longer......Anyone weld a bolt catch before ?

Sounds like the 9mm catch is gonna be the best/easiest answer. I have not compared the 556 and 9mm catch together,,,Anyone have a photo of the two side by side to show the length of the tip?
Thanks a ton

Shim the part forward by .018" ?

    How do the " green " followers work ?

God bless
Wyr

I tried shimming it forward and it still had trouble. I swapped out my green followers a while ago.
This rifle runs well on my USGI 30 rnd mags,,,,,just troubled that it will not lock open on other mags.

Yes. I have the same problem as you on an old cast Essential Arms lower. My USGI 20 round magazines are the worst offenders here. I tig welded this bolt catch. I weld for a living and it was a PITA as it is a small part. It can be done, but you run the risk of it breaking off. I don't know what material the catch is made of other than it is a casting and supposed to be quite hard. Mine has held up ok so far, but was too soft to begin with.

******Update - Fixed *******

Well, Brownells shipped the 9mm bolt catch very quick and I had to get out and take a stab at fixing this bolt catch issue.
After stripping out the old bolt catch, along with numerous measurements, I test fit the 9mm catch. It was very long, and that is just what I needed.


I fit several magazines and determined the overall length of the bolt catch needed to be in the area of .470 inches. That would allow enough room for different magazines and ammo, leaving enough room between the bolt catch and the back end of ammunition being fed from the magazine. I didn't want the bolt catch to drag across ammunition primers or rub the back of ammo while it was being fed from the magazine.
After fitting, a gap of a bit over .270 inches between the bolt catch and the base of ammunition.


This phot depicts the bolt catch final stages of fitting. I had to polish the bolt catch a bit in some areas. I found the top edge of the bolt catch was rubbing one of the bolt lugs.....The bolt catch was polished and slightly rounded where it was rubbing the bolt lug....This area was only rubbing when the magazine follower pushed the bolt catch upwards while the last round was being ejected from the rifle. After polishing, the bolt lug glides over the bolt catch without effort.


All that is left is to function test with live ammo, then cold blue the bolt catch. Overall, this was fairly easy to fix. I just had to take my time and test fit the new bolt catch a bunch of times. This rifle will now lock open on ALL my magazines, 30 rnd USGI, 20 rnd USGI, PMags, etc.  Very happy now.

It is possible that some out of spec receivers that have problems with PMags not locking open can be fitted with a 9mm bolt catch like mine

This is great news for me––thanks for bringing up the 9mm bolt catch.

Glad to hear it is working out for you.

On a side note, what item exactly is the 9mm bolt catch? My google-fu is a bit weak, and I can't seem to find a catch that looks like the extended one...is it RRA, Colt?

Thanks.

9mm bolt catch modified to fit out of spec receiver. 100% correct.
I used the Colt 9mm bolt catch, Brownells part #160-308-101

thanks for tacking this post

grrrrrreat post!!!

 Very informative.

I have a DPMS and was having the same problem, Except it was the bold catch was getting hung up on the magazine itself. I took my pocket knife and just shaved it a hair, now all my 20rd's work perfectly.  I know this wont fix them all, but something to look at on yours. I have the knife where you need to "clean it up"

Sorry for the horrible pics, its my phone.

Will a RRA 9mm bolt catch work or just the Colt? I have 2 receivers that I need to use this fix on great post thanks

Thank you for your help!

I was having this same problem and now see what the exact problem is. New bolt catch ordered!

Thanks, again a great help and very informative....<><....:)

Im having the same issue with an Olympic Arms Lower.  I just ordered 2 of those 9mm bolt catches and 2 roll pins.  Got another OA lower coming.  I wish I could have new lowers, but here in NY, we have to have pre ban if we want fun add-ons.   Thanks for this fix post, way helpful!!!

Great info! I just finished my first AR build and to my dismay, I have the same issue. I just ordered the RRA 9mm bolt catch and hopefully it resolves the issue. I do have a concern though. When Im looking into the chamber this last week trying to figure out if this will fix it, I notice that the bolt doesnt always seem to travel far enough rear to allow the catch to spring up. Wish I had three hands doing this but Ill pull back on the charging handle as far as it will go. I try to lock open the bolt manually and as you push it up, im hitting the bottom edge of the bolt. Sometimes I let the charging handle slip and slam, it locks open on my pmag feed lips. Any ideas on that one? Like I said, its my first build, the gun shoots, but isnt 100% functional! Did I do something wrong? bad mix of brands? I have a CY6 defensive edge lower, DPMS lpk, Spike tactical upper with the bolt and carrier that came with it.

Thanks for any help or advice.

I also just performed this modification... it does seem to work.
I got 'lucky' i guess on first cut.
seemed to have plenty of room between catch end and rounds in magazine.

I tried new followers in magazines first, but was still unreliable holding open when empty.

We'll run it out now and try....  hand cycling seemed to work with any old magazine i picked up.
Tell me more about blending the top of the catch...  I cannot detect any contact with bolt or carrier....

BTW... what lower?

Mine was Rguns.

Thank you for posting this...

rosco7even
you may have a separate issue...

"Tell me more about blending the top of the catch... I cannot detect any contact with bolt or carrier...."



The bottom leg of the bolt was able to drag along the bolt catch after I fit it to the receiver.

A bit of light file work and polishing on the top surface of the bolt catch took off enough metal to make sure the bolt did not contact the bolt catch until the catch was pushed upwards.



"BTW... what lower?"

Pac West Arms.



In the picture on the right, you can see the area on the bolt catch that had to be polished. It is the left side of the bolt catch in that picture. Since the bolt catch is a hardened part, the polishing may make the surface softer. Keeping that in mind, the polishing was done on the side facing away from where it contacts the bolt face.

Thought I would share this to maybe help someone else

I just had the same problem and here is what I found

After switching BCG's, changed catches and moved uppers and lowers around, I continued to have the same lower NOT catching the BCG.

It would not catch after the last round or when the charging handled was pulled with and empty mag installed.

It would not catch pushing the catch in either

At first I thought it was the lower (and it may well have been)

Then I got to comparing my lowers I had and it appeared that the catch on the one not working would not raise as high as the one that did work

So I took the catch off again and I could see where the catch was hitting the lower.

So, I got out my trusty triangular file and took maybe a 1/1000 off the lower where the catch was hitting, put it back together and it works perfect every time.

Only posting for others to learn from

I nearly sent the lower back after working with a gun smith at a shop and he thought the lower was bad too.

(and it was or the catches were out of spec or the spring was binding up)

Either way, just something to look at

Marc

The real solution is to have the manufacturer replace their defective lower.

from the original post,
"This receiver is slightly oversize in the cutout for the bolt catch. The bad news is the company (PWA) is not longer in business and I will not get rid of this registered assault weapon in CA "

Rifle still working well with this repair/mod.

Requested by op to be locked