Grendel mags?

[Rambozo]

No, it doesn't. A polymer mag could be made with thick walls for that portion which extends below the mag well, and thin walls for the upper part that's contained by the well. The mag well would reinforce the top part of the magazine, preventing the mag from bulging after it's inserted.

However, isn't it likely the top part of a loaded mag would bulge enough to hinder (if not prevent) insertion into the mag well, in addition to keeping a full or partially full mag from dropping free?

Why is wall thickness even an issue? Couldn't you just keep the thickness the same and adjust the stack width by increasing magazine length? It just be a longer magazine with a narrower stack. Why wouldn't that work?

[stanc]

Why is wall thickness even an issue? Couldn't you just keep the thickness the same and adjust the stack width by increasing magazine length? It just be a longer magazine with a narrower stack. Why wouldn't that work?

I think a "proper" double stack is necessary for two reasons:

(1) to keep magazine length to a minimum; and (2) to correctly align the top rounds with the barrel feed ramps.

What you propose would result in a significantly longer and heavier magazine, and because of the reduced stack width, it might not permit reliable chambering.

[pinzgauer]

You guys need to go back and look at the photo's I posted. The narrower stack creates spreading forces from the springs which cause the mag to bulge badly, much worse than it does with a proper stack. IE: The springs creates sideways (spreading) force rather than just vertical. In a proper stack each cartridge is in contact with the ones directly above and below in addition to the opposite column. Narrow stack only contacts at angles, creating the spreading force.

Regarding thinner walls, there is a reason the magpuls are so thick... it's about the only way without steel reinforcement to keep the walls from flexing and allowing the feed lips to spread. This is the problem with many past plastic mags, and even some current ones. drop or even jar the mag while not in the gun, it flexes, and rounds come spewing out. (Ram-line mini-14/AR mags were notorious about this, as are some others).

There is a reason even magpul provides a cover.... it takes the spring pressure off the lips and eliminates any chance of flex out of the gun. For the most part you can rap a 5.56 magpul and it won't spew cartridges though, but it's right at the ragged edge.

[stanc]

You guys need to go back and look at the photo's I posted. The narrower stack creates spreading forces from the springs which cause the mag to bulge badly, much worse than it does with a proper stack. IE: The springs creates sideways (spreading) force rather than just vertical. In a proper stack each cartridge is in contact with the ones directly above and below in addition to the opposite column. Narrow stack only contacts at angles, creating the spreading force.

Waddaya mean, "You guys"?

I understand the issues, but I do think it'd be possible to build a magazine like Rambozo proposes. Make the walls thick enough and they won't flex even with the narrower cartridge stack. The trouble is, such a magazine almost certainly wouldn't be viable for use in existing rifles.

[pinzgauer]

Waddaya mean, "You guys"?

Sorry, did not mean that the way it sounded. How bout: "there is a visual depiction of the issues caused by the narrow stack in an earlier post which may prove informative".

I understand the issues, but I do think it'd be possible to build a magazine like Rambozo proposes. Make the walls thick enough and they won't flex even with the narrower cartridge stack. The trouble is, such a magazine almost certainly wouldn't be viable for use in existing rifles.

Sure, you could make a Grendel / 6.8 pmag if it did not have to fit in standard mag wells. I'm sure there would be a huge market for that! From memory I think there is at least one plastic AR-10 mag. (Magpul 20 rd??)

wait, I see a market for filler blocks to allow AR-10 mags to be used in grendel barrelled AR-10's.

[stanc]

Sorry, did not mean that the way it sounded. How bout: "there is a visual depiction of the issues caused by the narrow stack in an earlier post which may prove informative".

Nope. That's saying the same thing, just in different words.

As I said, I understand the issues, so I won't learn anything I didn't already know by going back and rereading your earlier post.

Sure, you could make a Grendel / 6.8 pmag if it did not have to fit in standard mag wells. I'm sure there would be a huge market for that! From memory I think there is at least one plastic AR-10 mag. (Magpul 20 rd??)

wait, I see a market for filler blocks to allow AR-10 mags to be used in grendel barrelled AR-10's.

Ah, sarcasm. Ain't it fun to indulge in?

But, I think such an extra-thick walled magazine would fit in standard mag wells. The reason I doubt it'd be viable is because the closer spacing of the cartridges might not align properly with the feed ramps, and also because most shooters wouldn't like the extra-long mag.

[Rambozo]

I think a "proper" double stack is necessary for two reasons:

(1) to keep magazine length to a minimum; and (2) to correctly align the top rounds with the barrel feed ramps.

What you propose would result in a significantly longer and heavier magazine, and because of the reduced stack width, it might not permit reliable chambering.

I doubt that it would require a significant shift in the stack. Still, it isn't as if feed lip, follower, or mag geometry can't be also tailored to fit the different stack width.

[pinzgauer]

But, I think such an extra-thick walled magazine would fit in standard mag wells. The reason I doubt it'd be viable is because the closer spacing of the cartridges might not align properly with the feed ramps, and also because most shooters wouldn't like the extra-long mag.

OK, gotcha. Make the mag walls thicker to handle the side pressure due to the narrow stack.

You'd probably be down to a 15-20 round mag to keep the same form factor as a 5.56 30 round. You'd have to really want a plastic mag badly to accept that compromise, especially when 25 round metal mags work fine.

[bwaites]

I am not a Pmag (or any other polymer mag) fan. David Fortier published a great test article on AR mags in Nov 2009 in Shotgun news.

There is writeup here: http://bulletin.accurateshooter.com/...-shotgun-news/

I'll see if David will allow us to print the whole article, but basically, if I remember correctly, all the polymer mags failed an 8.5 foot drop test while loaded. The aluminum mags passed. Stainless steel would pass, I suspect. I like my Grendel mags as they are. Its really hard to beat the folded steel strength issues when you use the same form factor with polymer.

[stanc]

I am not a Pmag (or any other polymer mag) fan. David Fortier published a great test article on AR mags in Nov 2009 in Shotgun news.

I'll see if David will allow us to print the whole article, but basically, if I remember correctly, all the polymer mags failed an 8.5 foot drop test while loaded.

On arfcom he said "the Tango Down, PMAG and TAPCO all split down the spine" but "the Lancer and MSAR suffered little or no damage."

The aluminum mags passed. Stainless steel would pass, I suspect.

Um, apparently not: "The CProducts Stainless steel mag also died on impact with flattened feedlips."

http://www.ar15.com/forums/t_3_17/468826__ARCHIVED_THREAD____Shotgun_News_magazine_torture_test.html&page=1#i4345555

I don't see much applicability to the real world in torture "tests" like these. I mean, how often are mags going to be run over by a truck, or dropped from a height of more than 8 feet? Let's see some testing based on the way mags are used in reality.

[RangerRick]

On arfcom he said "the Tango Down, PMAG and TAPCO all split down the spine" but "the Lancer and MSAR suffered little or no damage."

Um, apparently not: "The CProducts Stainless steel mag also died on impact with flattened feedlips."

http://www.ar15.com/forums/t_3_17/468826__ARCHIVED_THREAD____Shotgun_News_magazine_torture_test.html&page=1#i4345555

I don't see much applicability to the real world in torture "tests" like these. I mean, how often are mags going to be run over by a truck, or dropped from a height of more than 8 feet? Let's see some testing based on the way mags are used in reality.

When you parachute in, you lower your ruck sack on a 20 foot line. That way it hits before you and your descent rate slows a little before you land.

Stuff in the ruck takes a pretty good shot. It would suck if your mags split.

I've had ammo, among other things, thrown out of a hovering helicopter to me. No place to land so it gets tossed out hovering over the trees.

It was all cased ammo though, and it is packed really well and survived OK.

I've also had ammo dropped to me with a poncho parachute out of a helicopter flying by. You literally tie a couple of ammo boxes to the 4 corners of a poncho with parachute cord. You stuff the poncho into a sand bag and make a static line out of 15 feet of parachute cord. You tie one end of the static line to a floor ring and the other to the closed end of the sand bag. Then throw the ammo and sand bag full of poncho out the door.

The weight of the ammo pulls the poncho out of the sand bag. It acts like a parachute, sort of. The ammo hits hard, but usually survives the drop. Here again, it was cased ammo, so it was packed very well.

I've seen guys fall over 8 feet, though, and it would suck to have the mags burst, even if it was your buddies that needed the ammo and not the guy who fell.

One of the guys in the Back Hawk Down incident fell 40 feet on the fast rope in and had to be medevac'ed, so it does happen.

Back in the days of the old C rations, our company clerk came up to me and handed me a dripping wet cardboard box and said "here's your dinner."

The chow had been dropped by parachute from a C-130 on a cargo pallet. The cans of food on the bottom of the stack burst on impact.

I had been out on a patrol and got in late, so I ate off the bottom of the stack. In my case it was a can of apricots, so they were still edible.

At least it wasn't the spaghetti! It was barely edible normally, much less oozing out of a split can.

RR

[bwaites]

On arfcom he said "the Tango Down, PMAG and TAPCO all split down the spine" but "the Lancer and MSAR suffered little or no damage."

Um, apparently not: "The CProducts Stainless steel mag also died on impact with flattened feedlips."

http://www.ar15.com/forums/t_3_17/468826__ARCHIVED_THREAD____Shotgun_News_magazine_torture_test.html&page=1#i4345555

I don't see much applicability to the real world in torture "tests" like these. I mean, how often are mags going to be run over by a truck, or dropped from a height of more than 8 feet? Let's see some testing based on the way mags are used in reality.

Well, it was 2 years ago!

Dropped? I've dropped my mags from height several times, jumping out of trucks, etc. I usually have jumped over a pickup side when its happened, and I'm 6'3" so they probably fell 7 or 8 feet. I've seen one run over, but it was a lost mag, and then found when the truck moved. It was soft ground and undamaged, and it was an aluminum mag.

The nice thing about stainless is you can bend the lips back, if the spine splits, you are done.

If I remember right, the MSAR wouldn't drop from his AR's, and he liked the Lancers.

All my stainless mags drop free, as do my Pmags, as do my aluminum mags. (Yes, I have about a dozen Pmags. They work, but for the price difference I would probably buy regular 5.56 mags now.)

I just wish we had more than one option, because having only one supplier of anything worries me!

[stanc]

When you parachute in, you lower your ruck sack on a 20 foot line. That way it hits before you and your descent rate slows a little before you land.

Stuff in the ruck takes a pretty good shot. It would suck if your mags split.

I've seen guys fall over 8 feet, though, and it would suck to have the mags burst, even if it was your buddies that needed the ammo and not the guy who fell.

One of the guys in the Back Hawk Down incident fell 40 feet on the fast rope in and had to be medevac'ed, so it does happen.

But in each example above, the mags would've been in pouches, protected and cushioned to one degree or another. They weren't naked magazines being dropped.

(IIRC, my favorite C-ration was scrambled eggs. Peaches were pretty good, too. )

[stanc]

Well, it was 2 years ago!

Don't they say the memory is one of the first things to go? I can't remember.

Dropped? I've dropped my mags from height several times, jumping out of trucks, etc.

Didn't learn after the first time? Gee, I thought I was slow.

Kidding aside, why would you keep using mag pouches that allow your mags to fall out so easily?

I've seen one run over, but it was a lost mag, and then found when the truck moved.

Yeah, but it's such a rare event it doesn't seem worth testing. It seems to me there are tests far more relevant to the way mags are actually carried and used. Of course, they wouldn't be as dramatic as driving over a mag with a big, camo-painted truck.

I just wish we had more than one option, because having only one supplier of anything worries me!

The former owners of C-Products should be making new mags very soon. That'd make two manufacturers, which would help.

[Trapper]

C rations? You guys forget the infamous Ham and Lima Beans. You could choke down the spaghetti if you had some hot sauce, and some C-4 to heat it up. Nothing made the ham and lima beans palatable.