AR Magazines, Buying The Right One, is There Really a Difference?

by Graham Baates November 17, 2017

YouTube personality, Graham Baates, takes an analytical look at some measurable performance differences in standard AR magazines. If you find this article useful, you should read AmmoLand’s related articles Best AR-15 Magazine For Your Rifle ~ Review.

USA – -(Ammoland.com)- What would a trip to the range or idle chat at the local gun store be without talking about the best magazine for your AR-15?

Name brands get tossed around worse than a Ford vs. Chevy argument, almost with the mysterious faith of the Glock vs. 1911 debate. During the Obama years, it seemed like there was a new manufacturer every month.

Times were easy then, everyone was afraid that fresh 30-rounder they saw on the shelf might be the last mag they’d ever see on a shelf and we gobbled them up. Now we all have dozens. Some of AR magazines work, others not so well. One AR rifle magazine that seems to work in one rifle doesn’t so work so well in another. I decided to take a look at the why without worrying about the springs or followers which are easily replaced.

While serving in the Army, one of the significant concerns were the feed lips on our aluminum magazines. Over-insertion, dropping them, shoving into a ruck or pouch, and even just time seemed to change the angle of the feed lips, and thereby the way rounds would strip. The now-lost art involved using a stripper-clip guide to bend them back into place carefully.

Who’s AR Magazines?

Author's original "Mag-Pull" Magazine ca. 2004 — Author’s original Army issue “Mag-Pull” Magazine ca. 2004

Now we’re in the age of polymers. Just as we have come to accept polymer guns, polymer gun magazines are widely used. What are the elements of the magic magazine have yet to be determined? Why do some AR magazines work and others not? I decided to take a look at dimensions and found some interesting (that’s relative) data. Before we dive into the numbers, a few disclaimers are in order. 1. My mag sample size was one(1pc ea). 2. The magazines are of various ages. 3. The calipers used were inexpensive but returned to zero after each measurement. 4. Alphabetically brands tested include:

American Tactical Imports
C-Products
CAA
D & H
Daniel Defense
ETS
Okay Industries (pre-2004 government contract)
Okay Industries (2016 civilian market production)
H&K
Lancer
Master Molder 20-round
Mission First Tactical
NHMTG (government contract)
MagPul PMAG Gen 1
MagPul PMAG Gen 2 MOE
MagPul PMAG Gen 3
ProMag 40-round
TorkMag 35-round
Troy Industries

The video explanation and demonstration of the entire test can be seen below.

AR Magazines by the Numbers

The first measurements made were in the mag catch area. I argue that these measures can influence the seated height and angle of the magazine, depending on your magazine catch. One would expect that these numbers would all be similar, but they weren’t. I can’t say which is best for your rifle, and in fact, they may all work, but it was an interesting finding.

AR Magazine Catch Height Measurement Chart. They are all somewhat similar except for ATI.

AR Magazine Mag Catch Width Measurement Chart: Width was less consistent. Does it not matter or is this how a magazine ends up askew in the well?

AR Magazine Mag Catch Depth Measurement Chart: The depth of the magazine catch can determine how firmly the mag is held prior to any adjustments on the rifle. Note the metal magazines have no bottom. — AR Magazine Mag Catch Depth Measurement Chart: The depth of the magazine catch can determine how firmly the mag is held before any adjustments on the rifle. Note the metal magazines have no bottom.

With the statics out of the way, I wanted to know how much these AR rifle magazines flexed when loaded. As mentioned earlier feed-lip width can influence a lot, so what happens to that measurement between empty and 50% load? What about 24 hours later, 48 hours later, and one week later? Can we store AR magazine loaded without effecting performance? This is where differences began to show. As a precursor, I measured feed-lip width before loading and immediately after a 50% load. Some of the changes were unexpected.

AR Magazine Mag Feed Lip Width Change Chart: Some lips contracted indicating that the body itself may have swollen.

AR Magazines feed lip Chart — A busy chart, but demonstrates the swell and contraction of AR Magazine feed lips. How did your brand do?

G B Guns

So what Magzine won? That depends on what you’re looking for. From this simple experiment, it appears that Mission First Tactical, Daniel Defense, 3rd Generation PMAG, and American Tactical are sure bets for maintaining geometry when stored loaded with ammo. All of these magazines have run well in my rifles except for the Master Molder and Daniel Defense.

Once again this is a sample size of one and is intended to serve as an informative study, not a definitive judgment.

About Graham Baates“Graham Baates” is a pen name used by a 15-year active Army veteran who spent most of his time on the tactical side of the Intelligence community including tours in Afghanistan and Iraq. Post-Army Graham spent some time in the 3-Gun circuit before becoming a full-time NRA Certified defensive handgun instructor and now works as an industry writer while curating a YouTube channel on the side. Visit Graham on Youtube .