history, development, mechanics, and practical considerations ian mccollum ian mccollum magazines...
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History, Development, Mechanics, and Practical History, Development, Mechanics, and Practical ConsiderationsConsiderations
Ian McCollumIan McCollum www.ForgottenWeapons.comwww.ForgottenWeapons.com
Magazines and Clips
Magazine
A magazine both holds cartridges and provides the force to feed them up so they may be chambered.
If it has a spring pushing cartridges up, it is a magazine.
Two Types of Clip
Stripper clip
(aka charger clip)
Used to load a magazine
En-bloc clip
(aka Mannlicher clip)
Inserted wholly into firearm
Clip Development
En bloc clips invented by Ferdinand Mannlicher in 1885
Stripper clips invented by Mauser in 1889
Ferdinand Mannlicher
Blow-forward pistol Short recoil pistol Straight-pull rifle Turnbolt rifle En-bloc clip Arguably Europe's
greatest gun designer
Mannlicher System
Steyr-Mannlicher 1886/1888/1890
Steyr-Mannlicher 1895
Italian Mannlicher-Carcano M1891/1938
Dutch M1895 Mannlicher
Pedersen Self-Loader
M1 Garand
Commission-Gewehr 1888
French Berthier 1890/1907/1916
Hungarian 35M
1895 Lee Navy (sort of)
Mannlicher System
PRO Cheap Light and compact Quick to load Very little to go wrong
CON Gun single-shot without
clip Some not reversible Difficult to “top off”
1895 Lee Navy
Hybrid clip, sort of Fed whole and loaded
into action Wire spring disengages
as soon as loaded; clip
falls out Not necessary for rifle use, just speeds reloading
Mauser stripper clips
Developed in conjunction with the Belgian M1889 Mauser rifle.
Mauser-style clips are a reloading aid, not a necessity.
Mauser Clip System
PRO Cheap Light & compact Disposable Rifle can be used
without clip No feed lips or catches
to be damaged
CON Slower to load
Detachable Magazines
First invented and patented
by James Paris Lee in 1879 Before either type of clip Design has not changed much
since 1879
Box Magazine
Basic principles Holds multiple cartridges Provides motive force to push cartridges into the
bolt's path to feed Usually includes feed lips to control cartridge Self-contained and generally removable from
firearm
Box Magazine
Materials Usually steel (strongest) Sometimes aluminum (lighter but fragile) Polymer (lighter and stronger)
Sometimes a mix, like steel-reinforced polymer
Mag Characteristics
Feed position – single or double? Number of columns – 1, 2, 4? Curvature? Feed angle?
Feed Position
Single easier to design bolt
Double loads much more easily
Most pistols are single
Most rifles are double
Number of Columns
Occasionally, quadruple stack
Russian RPK-74 Surefire AR Finnish Suomi SMG Italian Spectre
Feed Angle
Two factors: grip/magwell angle and cartridge rim
Luger – steep angle AR15 – virtually no angle
Rimmed straight-wall cartridges must be staggered in the magazine
Drum Magazines
Large capacity Noisy
Slow to load No longer typically used
Often fragile and/or unreliable
Failure Modes
Deformed feed lips can have several effects: Bullet nose too low; jams into feed ramp or front of
magazine body Bullet nose too high; extractor does not seat Case head not controlled; cartridge jumps loose
entirely Case head held too low;bolt rides over top of
cartridge case
Failure Modes
Feed lip geometry is critical to proper function, and is the primary cause of malfunctions in self-loading firearms.
Often cheap 3rd-party magazines have tolerances greater than allowable for reliability.
Even different factory models of the same gun can have this trouble – like Ruby pistols.
Failure Modes
A dented magazine body will prevent follower travel. Often magazine remains functions but with limited capacity.
A weak feed spring will fail to raise a cartridge fast enough to be fed by the bolt on a semiauto. Problem often presents on the last few rounds in the mag.