Sunday, October 11, 2015

Praxis: Rebuilding M16 magazines for fun and no profit. Magazine donation for smuggling project is like a trip down history road.

On Saturday morning, I received a package from a faithful reader which included 34 30-round and 6 20-round M16 magazines as donations for the smuggling campaign (probable destination, New York state, if Cuomo's state police taxpayer-feeding minions are paying attention). Looking through the haul was like a trip down U.S. Army procurement history. It also struck me that it might be a good time to pass along a description of how we check magazines for functionality and what steps we take to make them ready for shipment as "freedom-fighter" grade units.
As you might imagine, these come in used (some of them abused) and often covered in grime, sand particles and with the archaeological remnants of 100-mile-an-hour tape. The first step is to disassemble them, clean them internally, paying particular attention to the springs, making sure that there are no dings in the mag body to interfere with the follower, etc. We use acetone to remove any markings (some of them, occasionally, quite obscene) and the remnants of the OD duct tape. If found serviceable, all followers are replaced by MagPul anti-tilt followers which, although adding to the expense per unit ($2.00 each), takes care of most of the problems of feeding.
(Readers who have never disassembled an AR-15/M16 aluminum magazine may find these instructions at CTD helpful.)
It is, oddly enough, quite rare that we find a spring problem. Almost always the problems, if any, are traceable to two causes: the old black plastic GI followers and spreading or denting of the feed lips. Modern springs, especially USGI, are remarkably robust no matter how long the mag has been loaded. We recently unearthed a cache of magazines and ammunition that had been in a cave since the late 90s and two magazines were found to be loaded. We swapped the followers for MagPul anti-tilts, reassembled them and fired off the ammunition with which they had been loaded lo these many years without a stutter.
Our primary, initial check after cleaning and reassembly is detailed in this useful video: Quick inspection AR15/M16 magazines.
Unlike the maker of this video, however, we do not eschew using these tools available from Brownells: the feed lip tool and the feed lip gauge.
If the magazine fails the initial test described above, we then gauge it, checking the lips and if necessary and possible, use the tool to bend it back into place. If the mag body is swelled out of spec, we take it back down, use the body and other unserviceable parts such as the black plastic followers (which are meticulously scavenged -- nothing goes to waste -- in order to assemble "politician grade" magazines for the taunting of anti-firearm pukes in public office. The repaired mag is then set aside for our next trip to the range to test for functionality. If it performs flawlessly, then it gets shipped as a "freedom fighter." If not, it is cannibalized as described above.
Now we only do this for the standard thirty round magazines. We find the demand for the 20 rounders, especially Colt-marked twenties, to be such that we can wait for the next gun show and trade one 20 rounder for between two to five thirty rounders, which are then put into the production stream as described above.
We also have some collectors who look for specifically marked thirties for their collections. You can find information on the markings and makers of USGI magazines at these two sites: "M16 Magazine Manufacturer Information" and John Wesley, Rawles' "AR15/M16 Magazine FAQ."
This latest box was like a trip down US Army procurement history lane. Here's the breakdown of makers and markings:
Twenty Rounders --
Colt, Hartford CT Qty 4
Adventureline, Parsons, KS Qty 1
Universal Industries, Simmons Precision Products, West Haven CT Qty 1
Thirty Rounders --
Sanchez Enterprises, Mansfield OH Qty 2
Center Industries, Wichita KS Qty 6
LaBelle Industries, Oconomowoc WI Qty 1
Adventureline, Parsons, KS Qty 5
Parsons Precision Products, Parsons, KS Qty 6
Cooper Industries, Upland, CA Qty 1
Okay Industries, New Britain, CT Qty 12
Colt's Firearms Division, Colt Industries, Hartford, CT Qty 1
All in all, quite a collection, dating from Vietnam to the Iraq War.
At the same time, we received from another reader two MagPul Gen 2 P-Mags. Some lucky resister behind enemy lines will get those with a bit of luck of the draw.
Of course what with weddings, wedding exhaustion and other factors, I haven't had time to process the new batch yet, but I'll try to let you know what the acceptance/rejection/rebuild rate is in a later post.


AC said...

A 'how-to' on magazine fabrication, starting from sheet metal and spring wire would be interesting.

Anonymous said...

Fun fact: Labelle is now D&H, and they make mags for many manufacturers and distributers. High quality, reliable, well respected.

Anonymous said...

One thing to check on the Coopers, sometimes, quite often in my experience, they are far too wide to fit the magazine well of the lower receiver.

Miles said...

FYI Mike;
The Army sent out a recall, (like 25+ years ago) about Cooper magazine's functional and QC problems. Just my smallarms repairer/inspector opinion, but I would give them to the other side.