1911 Magazine Timing

[schmeky]

I now have 3 mags for my 1911/40, and all 3 are different in the length of the feed lips. One has "short" feed lips, one is "medium", and the other is "long". Each mag is from a different manufacturer.

Using the medium length mag, my pistol will now feed a shorter COAL beautifully, as opposed to the short mag, which would not feed a short COAL 100%. Why are there such variations in mags?

How is the feeding altered using different feed lip lengths? It seems as though the medium mag makes the cartridge "seem" as though it's longer, or does it?

 

[Jolly Rogers]

This article helped me understand some mag issues:
http://how-i-did-it.org/magazines/
And the second article delves into feed lip issues more thoroughly:
http://how-i-did-it.org/magazines2/
Joe

 

[schmeky]

Jolly Rogers,

Thanks, this was excellent reading.

 

[jungle]

Interesting articles, but the methodology left a little bit to be desired. In general the early release types are better for shorter COAL( think hollow points) and the original design is better for ball rounds which are 1.25 or slightly longer.

It is a fact of life that the odd push feed will happen with any of them depending on the particular pistol and ammo. Use what works for your pistol and ammo. There is no best for all circumstances.

Most well constructed pistols will do well with all good quality mags. The use of a particular type of ammo may dictate the magazine type.

 

[Oro]

Where and how the feed lips fully release the round determine three things, among others:

1) The angle and position of the round's nose when the rim leaves the magazine and the extractor/breech face take over control of the round,

2) The amount of influence the ramp has on feeding angle,

3) How much control is exerted over the round through the feeding cycle via the magazine, chamber, extractor and breechface.

Long lips with a late release keep the round under control tightly until it is well into the chamber and the extractor/breech take the round. This is the original style of magazine and what works best with ball ammo.

Short lips kinda "chuck" the round up at the chamber while it's still not well into the chamber, but they keep the bullet from interacting with the ramp and barrel throat much. Thus, they trade-off control for being able to digest odd bullet shapes or lengths. Wadcutter magazines are like this, and Wilson magazines are.

Medium, or, what I think you mean by "medium," "Hybrid" lips are between the two. These are like what are on Colt magazines and have been for a long time.

So, for ball ammo and most modern HP ammo, GI type lips feed smoothly and control the ammo the tightest. For wadcutters, SWC's, and home-loaded or less high-end HP ammo, wadcutter or "Hybrid" magazines will likely load better.

Perhaps with the "short" magazine it is releasing the rounds you are trying to load too soon, and the extractor is not grabbing it, or it's not close enough to the chamber to feed in correctly and you are getting stove-pipes?