I posted this on the Magpul forum with no response, any guidance is appreciated.

I just returned from the range after a disappointed experience with my brandy new Spikes upper on a PWA pre ban lower. I was finally able to do the sight zeroing I wanted to get done but had significant problems with ammo feed and failure to bolt lock on last round. I use 5 of the 20 rd. pmags. I had about a dozen failure to feed occurences and only one good bolt lock back after running 7 20 rd. mag loads. After I got home I examined the problem in detail. I first suspected my upper, but easily cleared that up with a little close examination.

Problem 1 - The rounds become slightly canted and stick in the mag, I noticed a problem originally loading the mags with stripper clips, but didn't think too much ot it. Rounds increasingly fail to feed as you get to the lower rounds (16-20). You can replicate the canting issue by pushing down with rounds in the mag.
Problem 2 - The follower sticks and becomes slight canted back and won't push the bolt catch up all the way..The follower can stick and cant back more than the 1 mm overlap rise needed to raise the bolt catch up after the last round...I repeated this problem and can see/measure it clearly with all 5 of the mags...this is not a weapon issue, clearly a mag issue.

You can replicate and measure these issues...I also think that there may also be a systemic friction issue with these composite/polymer mags. You can clearly sense the sticking when pushing rounds up and down in a partially loaded mag.

I have seen previous threads on this but no update. Has MAGPUL put out any info on these problems? What is the latest on this?
Can anyone recommend a site selling good dependable USGI 20 Rd. metal mags in black?
Thanks

We ship massive amounts of these 20-rounders a year and in the vast majority of cases they work just fine. However, sometimes some guns just don't like some products. Please contact our Tech Support Dept. for assistance.

Regardless, we are constantly updating our products as we're always trying to improve upon what we've already accomplished. Please keep any eye on our website for news and updates:
Magpul Propaganda

I don't know, could be a problem with the mags. Contact our Tech Support Dept. and we'll get some replacements out to try.

Note that the PMAG 20 does NOT have an anti-tilt follower. All straight-bodied magazines require a follower that can tilt to accommodate the tapered cartridge stack.

Though I have not had time to get out to the range with my five new 20-round PMAG magazines, I had a lot of problems with them when manually cycling dummy rounds (real cartridge cases and bullets but no powder or primers) through my AR. I would get the occasional failure to properly strip a round out of the magazine (the round winds up badly bent by the bolt jamming into the side of the cartridge case - Problem 1 in the OP). I also had a lot of problems with the bolt not locking back after ejecting the last round.

The feeding problem seems to be resolved after I smoothed up a lot of rough areas in the magazines and on the followers. I also waxed the interiors of the magazines and, more importantly, the springs with Johnson's paste wax (all excess wax carefully wiped out and surfaces left totally dry). The feel when I manually depress the followers is MUCH smoother operation now. They all used to feel quite gritty when depressing the followers with a narrow block of wood (such as a ruler).

The bolt lockback issue is now resolved. I discovered that the bolt catch was rubbing on the rear surface of the magazine and the friction was not being overcome by the upward pressure of the follower on the bolt catch's actuating arm. I filed a little off the rear face of the u-shaped opening of the magazine (shortening the front-to-back dimension by about .020") to allow clearance between the bolt catch and the rear face of the magazine. To see this interference, disassemble the rifle and work with only the lower with a magazine installed. While manually pushing on the magazine follower, carefully observe the rear surface of the magazine and the bolt catch. The bolt catch had been scraping on the rear surface of the magazine and now I have about .010" to .015" clearance between the two. After this tweak, I have had no failures of the bolt locking back after ejecting the last cartridge.

I believe that the roughness of the spring surface was the biggest cause of the "gritty" feel I experienced with the new 20rd PMAG magazines. I forgot to mention that I used a 3M scrub pad to smooth off the spring's outer surfaces before applying the wax. The total job of smoothing out some molding lines in the plastic parts (body and follower), smoothing the spring's surfaces, and the wax job has made a tremendous difference in how smoothly the follower can move in the magazine. This means that there's now less to hang up the movement of the follower and cartridges in the magazine.

If my work had not solved the problem, I would be on the hunt for a stronger magazine spring.

I did experience a roughness when manually pushing on the followers in all of the five 20rd PMAG magazines I bought a couple of months ago. I bought them from three different sources and found two different manufacturing date codes on them. The springs in all of them were a bit rough and my polishing the springs and then applying a light coat of wax on the springs and inner surfaces of the magazine bodies made a tremendous difference in how smooth the movement was. All five of my 30rd PMAGS which I bought in December operated just as smooth as delivered as my tweaked 20rd magazines.

Sorry, no ETA. Still testing and tweaking. The first production ready batches will be going to MIL/LEO and OEMs for evaluation and realistically we'll be looking at a Fall release for public distribution

I have two of the 20rd Pmags and perfer to use them when shotting phrone and bench rest BUT I also have a BAD Lever and Love how it helps with the function of my rifle. I had no problems with the setup untill after the first 300 rounds or so through the rifle and now the 20 round Pmags won't hold open the bolt after the last shot. If I remove the BAD Lever or use the 30 round Pmags I have no problem. But with my bipod set up and the way i shoot I cant use the 30 rounders when phrone or bench. I called customer service they said it is because of the tilt follower. it dosen't have the ablility to over come the extra mass of the BAD Lever. I haven't found any fix for this yet other then getting the Bushmaster 20 round curved mags but I don't know if there gonna be to long to shoot with the way I like. I have already gone threw the rifle and checked for over or under gasing or short stroking and none of those are an issue.

Has anyone come up with a fix for this?

Sorry not trying to HI-Jack this Thread

Reasons why I do not like "Plastic Mags" or polymer or what ever you want to call them;

1. They are plastic and im sure plastic on plastic wear will eventually cause some kind of flaw.

2. Theres a reason why the Army banned the Pmags (this i dont know why but im sure theres a good reason)

3. I prefer a metal mag that way they will last pretty much forever.

The Americans back in the day used to make steel and aluminum products would last forever. This age of plastics and such, just seem cheap and easily breakable. Old school shit used to always last forever, nowadays companys seem to make crap which yes may be cheap, but you will have to purchase another one in a few years. (this goes for all types of machinery, cars, etc) Even houses today are made cheap as shit.

Reading the OP....I didn't think you could USE Stripper Clips with Pmags...
SASS