Fixing PMAGs to drop free

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blsonne

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Hello lads & ladies,

So after the last CQB clinic I determined that when I had some spare time, I was gonna figure out why 4 out of my 9 PMAGs (latest model) wouldn't drop free from my CQ-A.

I put the micrometer across the mag at the point where the rivet was, and they generally measured from 2.6500 to 2.6545 for the ones that didn't drop. The ones that did drop free were usually around 2.5510 or 2.5520. OK, that's quite a difference, so I took a file to a couple and brought the measurements down to 2.5510... w00t w00t, they drop free now.

No need to candle wax or adjust other aspects of the mag. I inspected the rivets with my otoscope (seriously, spend the money on a Dr. Mom Otoscope, they're very handy http://www.drmomotoscope.com/ especially for us reloaders) just to confirm that there was nothing odd with the rivet and that I did not damage them nor come anywhere close to unpinning it. The rivets are still solidly in there.

It'd be nice if the places that sold these made this adjustment before rebagging & shipping them, but I thought folks might appreciate the measurements. A fine file and 5 seconds of medium pressure when you do it are all I needed.
 
Having your magazines drop freely is always a bonus, but can you load 5 rounds and fully seat the magazine in the carbine on a closed bolt?

Good question - I don't remember any problems like that, but I did not check the newly fixed ones. Might as well check and measure them all again. Good catch, that's probably more important then them dropping free...
 
blsonne said:
It'd be nice if the places that sold these made this adjustment before rebagging & shipping them, but I thought folks might appreciate the measurements. A fine file and 5 seconds of medium pressure when you do it are all I needed.
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If they did, the mags would get scuffed up from the mag catch and look used vs new. If you take your time (and not much of that is required), you will get a nice clean drop before filing through your rivets.
 
Yesh, 2 out of 9 of the pmags wouldn't seat reliably with 5 rounds, but a tweak to the follower should take care of that.
 
Got to say, whoever is installing those rivets in the PMAGs need to lower their measurement by another 1/8" or just shy of it. About 6 out of a dozen pmags I got need a firm slap for them to lock in or need to have a tiny amount of the follower's leg sanded down. Just out of curiosity, does anyone have a source for AL counter sunk rivets? I could only find steel ones which are a bit of a pain to remove. :p
 
Found some on e-bay. Don't come cheap - 20USD shipped for 50. Might have to go to a fastener specialist and inquire.

Edit: Found another source after some quick googling.. ht tp://www.aircraftspruce.ca/catalog/hapages/solidalumrivets.php about $20 per lb and www.rivetsinstock.com seems to have them for $6/100 but I'm not sure if they ship to Canada
 
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TRaTSeRiF said:
Found some on e-bay. Don't come cheap - 20USD shipped for 50. Might have to go to a fastener specialist and inquire.

Edit: Found another source after some quick googling.. ht tp://www.aircraftspruce.ca/catalog/hapages/solidalumrivets.php about $20 per lb and www.rivetsinstock.com seems to have them for $6/100 but I'm not sure if they ship to Canada
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Thanks. The ones from Aircraftspruce are solid rivets, not blind rivets. I did some googling and found Acklands carries em in Canada. Don't even both with Home Depot, at least the one by my house had all of 5 sizes and an assorted box. :)

h ttps://www.acklandsgrainger.com/AGIPortalWeb/agi/_/N-0?Ntt=countersunk+blind+rivets
 
Pmag rivets are installed by the folks at magpul. They pin to 5 like required but it's too tight on a closed bolt. I'm sure it's such a small market that they don't care lol. Anyways take the rivet out, and make a very small half moon in the back side of the follower where it would touch the rivet. Really a couple of millimeters indent is all you need. Go small and test by inserting new rivet into the old hole and attempting to load 5 rds. Should hold 5.5 to be good to go. Once there rerivet and Bob's your uncle. Slapping the mag in without doing this will cause horrific stoppages. Cost me many points at a Cqb match. Once this was done there were zero problems.
 
Longshot said:
Pmag rivets are installed by the folks at magpul. They pin to 5 like required but it's too tight on a closed bolt. I'm sure it's such a small market that they don't care lol. Anyways take the rivet out, and make a very small half moon in the back side of the follower where it would touch the rivet. Really a couple of millimeters indent is all you need. Go small and test by inserting new rivet into the old hole and attempting to load 5 rds. Should hold 5.5 to be good to go. Once there rerivet and Bob's your uncle. Slapping the mag in without doing this will cause horrific stoppages. Cost me many points at a Cqb match. Once this was done there were zero problems.
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Doh! Thanks for the half-moon tip. I've been sanding off a couple mm off the whole leg, didn't think to just do a half-moon notch. lol
 
No worries. Either will work but a couple of strokes with a round file will sort that problem right out! Just go a little at a time as there is no going back after lol.
 
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