1911 Magazine Design

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Just recently, a flurry of sudden interest has emerged due to my sending a test magazine to a member in hopes of addressing his recurrent 3-Point Jam/Failure to go to battery headaches. It’s a specific type of magazine, that…although is only a slight modification of hundred year-old technology…is largely unnoticed by the large percentage of 1911 owners…except in the occasional statement that a pistol is 100% feed reliable only with the OEM Colt 7-round magazine.

 

The magazine design is centered on the feed lip geometry, and is Colt’s own patent, and they’re made to Colt’s specifications by the vendor. I tagged it “Hybrid” and it stuck. Even Check-Mate refers to it as such in their catalog. My 15 minutes of fame, I suppose.

How and why this particular design came to be…like so many other things…can be traced directly to the AMU and Bullseye competition.

Early on, the only ammunition available was hardball, and…because the 1911 was designed around it, all was well. Then, a new bullet design appeared in the form of the classic Hensley & Gibbs #68. The designer understood that the overall cartridge length had to approximate that of hardball in order to have a prayer of feeding…and thus is came to be.

The bullet was wonderfully accurate, and because of its shoulder, it cut clean holes in the target, giving the shooter a better chance of cutting the next higher ring.

The problem was that the sharp shoulder tended to grab the narrow barrel ramps and cause 3-Point Jams. Alibis are granted for misfeeds, but it broke the shooter’s concentration. The “Throated” barrel was born. It helped, but didn’t completely cure the problem because the magazines were releasing the odd-shaped bullet just a tick too late. Armorers began opening up the forward section of the feed lips to effect an earlier release, and before long, a forming die was developed to create a consistent and repeatable release point…and it worked well.

In the 60s, Colt was still making a few magazines in-house. They didn’t need to make many because they had a stack of’em left from the anticipated post-war contracts that never materialized. There wasn’t a lot of market interest in the 1911 in those days, so they figured that the stock of magazines and their small capacity to make them would last well into the 21st century. Those magazines were, of course, standard USGI “Hardball” magazines and the barrel ramps were still the original narrow design. At that time, hardball was still the only ammunition commercially available. Those who cast and handloaded the #68 had the forming dies.

Then, a new bullet burst upon the scene by way of Super-Vel corporation in the form of a 185-grain jacketed hollowpoint, and it set the world on fire. Finally…the folks who carried and used the “Yankee Fist” had a more effective bullet. The problem was that many guns wouldn’t feed it. “Throating”…or more correctly…”Ramping” the barrel entrance to the chamber helped a ot…but still didn’t address the problem of too-late release with the shorter overall length and the wide, flat hollow cavity.

Colt…knowing the success that the AMU armorers had with their forming dies…took a close look at it, and simply tooled up to form a defined, timed release point in the full-tapered hardball feed lips…and the “Hybrid” was born in response to the grownng demand for feed reliability with hollowpoints.

The hybrid feed lip design blends the best of both worlds, and works equally well with long OAL hardball and short OAL hollowpoint bullet types, as well as the mid-length Hensley&Gibbs SWC. But…the trend in target bullets started to move away from the #68 when bullet designers realized that an edge in accuracy could be realized with more bullet at full diameter…making it necessary to reduce the length of the important nose in order to “make weight” and the “Wadcutter” magazine was the result.

With its early, abrupt release point, it worked fine with short OAL SWC ammo loaded to reduced velocities and recoil levels. No need for power if all you’re doing is punching holes in paper, after all, and all high recoil levels do is promote flinching and make it harder to maintain a consistent grip on the pistol. If the effects of recoil are minimized…no need for an overly strong magazine spring to maintain control of the cartridges.

Less recoil means longer, more productive practice sessions. A lighter spring makes loading the magazines less tiresome, and it’s all good…until you introduce longer, full-power ammunition into the equation. Then, things sometimes go a little haywire.

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