I just got 4 Pmags as testers, and I am a bit sceptical about the PLASTIC feed lips.  My concern is even greater after reading mag pulls instructions claiming that you need to put the caps on them if you store them loaded.  As I see the caps press the rounds down into the mag so that they don't sit on the lips.  My HK USP polymer mags have stainless feed lips, can the P mags hold up under high heat/ hard use? is storing them loaded going to distort the lips?

I believe the standard response is that Magpul has a loaded 30 round pmag being used as a paperweight somewhere that's been sitting for at least 1 year with no feed lip deflection.

In my experience (on my 20's) there's been no problems with the feed lips.  Though I do use the covers to prevent debris from entering the magazine (loaded or unloaded).

tag.    I also wonder if the cycling of the gun will eventually wear down the top of the feed lips as the metal parts move over them.

Thanks!  your post instills piece of mind.  I will be ordering more soon.

Quoted: Quoted: tag.    I also wonder if the cycling of the gun will eventually wear down the top of the feed lips as the metal parts move over them. We have some mags in testing with the military that have gone over 250,000 rounds without issue. The polymer compound reduces friction with the casing and so it wears very little.

How many times have they had to replace the mag spring in that?



Quarter million rounds...wow. That's a little over $87,000 worth of 5.56 ammo at todays going rate.

Post the saw video seems like more than enough proof to me.

Not sue on Pmags but I had a couple problems with Thermold's. They also fit and feed great. The problem was in winter use. I noticed in single digit temps I had one mag that would miss feed. Looking at it the weld or seam was split on the back of the mag allowing the mag to open up or separate sightly. I had this happen to two magazines out of about 10 in use. Thermold replaced them at the time. I am a firm believer of having a mix of equipment. The Thermolds are great for anything but cold weather use. I would stick to an aluminum or steel mag for freezing temps.

P-Mags aren't Thermolds. Magpul has excellent customer service, if you have a problem with something, call them and they will make it right.

Quoted: P-Mags aren't Thermolds. Magpul has excellent customer service, if you have a problem with something, call them and they will make it right.

Big +1

Quoted: Quoted: Quoted: tag.    I also wonder if the cycling of the gun will eventually wear down the top of the feed lips as the metal parts move over them. We have some mags in testing with the military that have gone over 250,000 rounds without issue. The polymer compound reduces friction with the casing and so it wears very little. How many times have they had to replace the mag spring in that? Quarter million rounds...wow. That's a little over $87,000 worth of 5.56 ammo at todays going rate.

ahhh yes, one of the few things my tax dollars do that I approve of.  

Magpul-

Have you done any accelerated creep tests, run to ASTM standards? Plastic will creep at "normal" temperature ranges when it has a constant load on it. I have been wondering how the Pmags hold up when loaded long term. A year at room temperature does not tell you anything if you are planning on storing mags for say 20 years. A metal mag can do this with no problem. The Pmag may be able to do it with flying colors as well-all depends on what plastic is used and the exact geometry of the mags. I am positive that you know a lot more about plastics than I do, but I am wondering just how durable these mags are. I also know thta you can't be giving out propriatary info on the net, but if you could share any test data with us I would appreciate it. I am sure it would reassur emany other folks as well.

I just ordered 10 more Pmags but don't plan on keeping them loaded long term. May wind up doing it, but I need to see more proof that it won't hurt them first.  

Quoted: Quoted: tag.    I also wonder if the cycling of the gun will eventually wear down the top of the feed lips as the metal parts move over them. We have some mags in testing with the military that have gone over 250,000 rounds without issue. The polymer compound reduces friction with the casing and so it wears very little.

What about us guys that shoot more than 250,000 rounds a week?