Monday, November 07, 2011

Magazine issues.

Og has his evil black rifle all put together and is lacking only time to get it to the range.

A discussion in his comments section brought up some good points about AR magazines.

I know I harp on this constantly, but magazines are wear items. Further, they are the weakest link of any weapon that feeds from detachable mags, if only because they are easier to drop and lose than the rest of the gun, so it's only common sense to have a bunch of 'em.

Until a few years ago, if your rifle was an AR-15 (or other type that ate out of STANAG magazines), the easiest way to do this was to buy a bunch of GI surplus aluminum mags. It's still a pretty inexpensive solution to the magazine problem, but it can have its downsides.

Left fully loaded for extended periods of time, the spring will push the column of ammunition against the feed lips, gradually spreading them apart. Your first indication that this has occurred will be the occasional double feed. If these are ignored and the magazine left in service, you may get a chance to see a "volcano", as the lips get spread enough to allow the magazine to regurgitate three, five, or even a whole magazine's worth of cartridges into the upper receiver.

Also, GI magazines have been loaded by GIs, who are given stripper clips of ten rounds and a handy little adapter to get them from the clip into the mag. If the GI is a lazy GI, he might have braced the top round in the clip against the edge of a handy table and the magazine baseplate against his tummy and leaned against it to "ZZZIP!" load ten rounds really quick-like, apparently without considering that this then allows the feed lips of the aluminum magazine to crash into the edge of the table with his body weight behind them.

While this will give him a splendid chance to practice his "SPORTS" malfunction clearance drills, it will likely not make you happy when you purchase the surplus magazine he has borked.

This can be totally avoided by buying new magazines. (And not doing these things yourself, of course...)

24 comments:

Tango Juliet said...

PMAGS are your friend.

Tam said...

I agree. Some people like the metal GI mags, though.

og said...

Since all the people I know who are AR shooters seem to have the same regard for the Pmags, I'm sold. No sense reinventing that wheel myself. Cheap as chips, made in USA, what's not to like?

Anonymous said...

I have one Pmag that will not work with more than 24 rounds in it and it is marked so for failure drills. I had a friend's new Pmag go belly up in the same fashion at the KTRS match last month.

Nice thing is I'm sure if we sent them back to Magpul they would make it right.

I was taught at the church of examining every round you put in your magazine. Still only put 28 rounds in the 30 round magazines even though I'm assured Pmags run just fine fully loaded.

Gerry

Boat Guy said...

Dunno if PMags are the same as MagPuls, but those have stood up well for us and can be had for about $14. As to the GI mags; the Brit "AR" mags intended for the SA-80 are extremely well made - by H&K.

RobertM said...

Yep, Magpul Pmags. I just finished putting an AR together myself and will be taking out to shoot later today.

I try to buy a magazine every time I'm in a gun store. Generally it keeps the local Merchant of Death from glaring too hard when I'm drooling over guns I can't afford just yet.

Anonymous said...

Metal ones are hard to diagnose if defective. Pmags, much simpler.

BTW, SPORTS is a super way to turn a slight malfunction into a serious stoppage.

Al T.

WV - alsaus.... My sausage is sorta personal.

Mulliga said...

The only thing I don't like about Pmags is that the second loaded round in the mag tends to tilt up, making it slightly hard to seat on a closed bolt. On the other hand, the storage cover doubles as a nifty baseplate protector when you're doing reloading drills.

Jerry said...

Depends on the gun. It's pretty much impossible to buy new magazines for my beloved High Standard Supermatic Trophy that work. However, disassembling the magazines periodically and replacing the magazine springs every 5 to 10 years does absolute wonders for function.

Will said...

I left a couple GI type loaded with Russian short .30, and the spot welds broke, IIRC. Body halves separated enough to keep it from fitting in the magwell. Feed lips looked ok, though!

Just My 2¢ said...

Ya know, one big advantage that Pmags and Tango Down ARC magazines have is that you KNOW when the magazine lips are bad. They crack and break. Sometimes you don't know that your aluminum magazine lips are loose until you get a double-feed or when it pukes all the rounds out.

Brownells has a feed lip GO/NOGO gauge, but I'm really disappointed over their pricing for such a simple little tool.

TomcatTCH said...

all I need to know about GI pattern aluminum mags I learned when replacing the green followers with Magpul followers.

Out of 40 new or almost new magazines, I have 4 (that's 10% folks) that will not allow a Magpul follower to be installed. The mag bodies are too tight. On one copy a follower would sorta fit, but then wouldn't move freely at all.

How's that for tolerances?

T.Stahl said...

Yeah, those HK 'high reliability mags' are so great, the Brits ordered one million (1,000,000) Magpul EMAGs to replace them.

atlharp said...

I tend to agree on the aspect of Pmags and their second round issue. Troy Battle mags are the best mags I have used thus far. They are durable plus come with some Neato. Magpul thing on the bottom. They are around the same price as Pmags too.

Fudgie Ghost said...

Some of us in states that still have AWB's can't have PMAGS, or ANY new mags. . . .Have to make due with new springs and followers. . . Hey Tam, maybe you or someone could post two GI mags side-by-side showing "ok" and "not ok" feed lip comparisons?

Tam said...

Fudgie Ghost,

See above re: Brownells feed lip gauge. It's not something you can necessarily detect with a MkIMod0 eyeball...

DirtCrashr said...

The Brownells ones are pretty good. I have a bunch of "re-build kits" that are just awaiting a serious civil-unrest situation.
Tony-Fodder Ride-Fast who doesn't blog anymore or tweet had a neat post on how the Germans in WWII were dependent on magazines, big-ass magazines in airplanes and in tanks - whereas we used belts for bullets in our planes and tanks and stuff. Apparently some of the German Top Brass were heavily invested in companies that made magazines and were traded on their stock-market during wartime, and were making a pile of side-money - until it all went pear-shaped for them...
I wish he'd activate his blog again.

libertyman said...

Geez -- I don't know about the metallurgical reasons why a mag spring would or could deform feed lips at reasonable temperatures. How long is a long time? How much pressure is on the spring?
Usually deformation of metal under stress and higher temperatures is due to "creep", and it does happen, but I wonder if this is what happens here.

Firehand said...

Son mentioned that the biggest reliability problem they had with the M4/M16 in Iraq was magazines; so many they had were flat worn to crap.

Fudgie Ghost said...

Tam: oh, didn't see that reference above my comment---thanks. . .But, $60 for that little piece of steel? Oh Lawdy! Too rich for my blood. . . For that price I would expect it to detail my car or something. . .

McThag said...

$60 to find out if the mag I have is good or four new mags?

Seems a no brainer.

McThag said...

Metal mags are my only option for the 6.8. Expensive metal mags in two cases and not sure I trust them after managerial/ownership change cheaper in the other.

The retro thing causes me to buy metal for the 5.56 guns. Brownells does good there.

I'd love to see a torture test for the P-Mag v Troy Battle Mag and the Lancers though. That might cause me to make an AR that fits the narrative and would be OK in using a modern mag.

Tam said...

McThag,

"Seems a no brainer."

If you live in a free state. :)

Jonathon said...

Good synopsis Tam. Not that it really matters what causes the magazine to fail but something the Big Army had to stop doing was smacking a loaded magazine on your Kevlar/MICH/something hard to "seat" the rounds in the back of the magazine. Of course, that weakened the spot welds pretty quickly. A quick, but hardly fool-proof, test is to squeeze the top most rear corners of the magazine. If the spot weld is getting ready to crap the bed, you can often hear a metallic clicking or grinding.

So, yeah, if you like seating your rounds, just do so with your hand or your thigh as a nice fleshy substitute to something that will eventually ruin a magazine (and you NEVER find out until you're on the two range).