Colt 1905 .45ACP vs. Other Big Frame pre-1911 Colt Autos

[rhmc24]

In keeping with my 'share the info' belief, here is some I have gathered of possible
interest to vintage Colt-Auto folk. I'm into the big frame pre-1911 Colt Autos, specifically,
1902 Sportings and Militarys and 1905s. I don't care much for the 1903 Hammer which
is just a shortened version of the Sporting. I like the .25s, the .32s and .380s but don't
own any. I just can't get into another collection specialty. I'd like to have a nice 1900
but so far none I can afford. This info about the 1902 & 1905 will be news to some people.
Below is probably my best 1905.



The kinship of the .45ACP 1905 and the .38ACP 1902 is much closer than it first
appears. Colt took its 1902 Military, shortened the frame and barrel from 6" to 5",
made it a little thinner-walled internally, put in a .45ACP barrel, magazine and had
its .45ACP Automatic.

Late 1800s military around the world, US included, had all pretty well decided on the
smaller calibers of .38 and smaller and were leaning toward semi auto rather than
revolvers. Colt, starting with its .38ACP 1900 Model, developed it into the .38ACP
1902 Military in hopes of getting US Gov't orders. The US Army, based on poor
performance of the .38 in the Philippines, then changed preference from the .38 to .45
caliber. Colt, ready to meet a challenge, promptly converted the .38ACP 1902 Military
to the 1905 in .45ACP. From there it kind of 'growed like topsy' thru several mods and
models to the 1911.

Now about kinship. Modifications and improvements on the 1900 became the 1902
Military. The basic design of internal parts remain unchanged in all the big frame
Colt automatics including the 1911.

Within the 1905 and 1902 family most internal parts not caliber or cartridge diameter
related are physically interchangeable. For example, a 1905 slide will fit the rails of
a 1902 and vise versa. Hammers, sears, disconnectors, mainsprings, tri-spring, recoil
springs, mag catch, pins, links, takedown plugs, firing pin, etc. will physically
interchange. There are differences affected by barrel length, such as recoil spring,
spring guide, takedown plug, etc.

In assembling several of these pistols from unrelated parts I have found a high degree
of interchangeability. Some differences I have not decided if caused by original
production tolerances or intentional differences for functional purpose. Most
differences I have noticed are in hammer cock notches vs. sear, and disconnectors. In
most cases just switching a part cleared an issue.

A few comments are worthy of note. The hole pattern (pins & screws) for internal
parts is identical on the frames, typical of Colt overall precision. There are a few other
kinks such as the slide stop interchanges between the 1902 Military and the 1905 but
requiring adjusting its interface with the magazine cartridge follower. A 1911 recoil
spring fits but probably of incorrect force value. None of this is to say that 1911
internal parts interchange with the earlier models, just the design and function is the
same.

A few omitted details could be discussed. Feel free to question, comment or PM.

[ralph7]

a lot of interesting points that i was not aware of. i also own nothing automatic earlier than a 1911.
question?
there's no question you've been around the block and then some, sir.
my hat's off to your experience and expertise.

[Malysh]

Thank you Robert. This is an excellent presentation on a little known subject. I certainly learned a few things.

[JudgeColt]

None of this is to say that 1911
internal parts interchange with the earlier models, just the design and function is the
same.

Perhaps this is not what you mean by that statement, but the weak point of the Model 1900 et seq is the parallelogram linkage and cross-bar slide retention system. The Model of 1911 eliminated most of those features, keeping only one swinging rear barrel link, which Browning soon abandoned on the P35 "High Power" design. To me, all of that means that the major contribution of the M1900 et seq was to show what did not work, which all led to the development of the Model of 1911. Thoughts?

[kwill]

Good discussion! I am also thankful that JMB examined a Luger before he finalized the grip angle on his large frame autos. The early designs were not ergonomic at all. He probably could have gone another five degrees on the grip angle as evidenced by the need to go to an arched main spring housing with the M1911A1.

[Oyeboten]

Perhaps this is not what you mean by that statement, but the weak point of the Model 1900 et seq is the parallelogram linkage and cross-bar slide retention system. The Model of 1911 eliminated most of those features, keeping only one swinging rear barrel link, which Browning soon abandoned on the P35 "High Power" design. To me, all of that means that the major contribution of the M1900 et seq was to show what did not work, which all led to the development of the Model of 1911. Thoughts?

Why or where is it said, that the 'Parallel Rule' design 'did not work'?

Far as I ever saw, heard, read, or have found out for myself with my own Guns, they 'worked' splendidly.

The 'Single Link' cost less to Manufacture...and the 'notch' Lug, even less yet.

Possibly, the design of the 1911 was a little more robust as well, or allowed ( with an appropriately stiffer Recoil Spring, ) for more powerful Cartridges.

Otherwise, I do not know on what basis anyone could claim an improvment, even if we do see changes having been made...assuming all changes MUST be 'better' and or MUST imply the prior design details 'did not work' ( or must have been deficient, ) is not really the same as understanding, or, is a kind of interpolation.


The 1911 .45 Auto is really a scaled up 1903 .32, with some changes to the Slide Relase and Safety...hence, is from that 'Branch' of the Tree, and not the same Branch as the .38 Automatics had been. And, had the Army so elcted, it would have been a scaled up .32 with an internal Hammer, too.


Same Trunk, different Branch.

[rhmc24]

Judge, you are right in all you say. OCS again, I "oughta, coulda, shoulda" explained what I meant about 'internal parts', basically those in the grip area. My 'omitted details' I mention at the end - actually a lot of them the more specific one gets.

Change from the parallelogram barrel lockup system was hardly a detail but the aim of the article is/was to discuss the comparison of the various 1900 to 1905 pieces. Perhaps leaving out mention of the 1911 would have been better, depending on one's perspective, but I consider it worthwhile to mention the evolution of the lockwork began with the 1900-1905s. Most any judgement call is subject to dissent. Cheers!

PS: I think it is generally understood that 'lockwork' has to do with hammer, trigger, sear, mainspring etc. At least, my main experience is based on half a century of restoration work on 'lock, stock and barrel' guns prior to 1800 - 'lock' in that context, the mechanism that fires the gun.

[Rob Greer]

I absolutely LOVE the progression of the design from the 1900 to the 1911. Thank you for pointing out some of the finer points of the early large frame designs!

[JudgeColt]

Oyeboten, I never said the parallelogram linkage did not work. Actually, to me, the design is more "pure" than the tilt barrel designs, but the extra parts certainly create more areas to fail. I said the design progressed away from that more costly and complicated breech lock method. If the design were so superior, it would be in common use today. It is not. In addition, the slide retention bar is clearly a weak design feature of the Model 1900 et seq that was rightly abandoned.

I see NO relationship at all (other than the name and a self-loading mechanism) between the blowback, fixed barrel Model M, and the Model of 1911. As rhmc24 points out, the Model of 1911 has roots in the Model 1900 et seq. The progression went through the Model (Contract) 1907, Model 1909 and Model 1910, NOT through the Model M. Bady has a detailed description of the development of the Model of 1911 that will help explain it all.

rhmc24, had you actually used the term "lockwork" in your first post, I would have had to agree, but the recoil mechanism is the area of greatest evolution in the development of the Model of 1911, so that is what seemed most important to me.

Mr. Williams, I wonder what Gaston Glock was smoking when he designed the grip angle of the Glock 17? I hate it, probably because I grew up on the Model of 1911. (I prefer a flat main spring housing to the arched housing.) I even much prefer the grip angle of the Model 1900 et seq to the Glock. Judging from the popularity of the Glock, I am apparently in the minority, although I have a fairly large support group in fans of the Model of 1911 and all its clones. I find the Luger grip angle to be too far the other way, although I do not find it anywhere near as odd-feeling as the Glock.

[rhmc24]

Judge I thought it was pretty clear that my article was about the 1900-1905 type & its points of similarity and/or parts interchangeability. I listed most of the parts in common at issue. The evolution of the parallelogram barrel-slide lockup vs the 1911 single link tilt-lock (for lack of a better name) is really a separate discussion.