Why do most 1911s have the flat mainspring housing?


April 13, 2003, 09:27 PM
I find the curved backstrap much much more confortable but it seems that allmost all of the newer 1911s have gone with the flat style. Why? Is there a reason? Do most people like the flat backstrap? I'm I just weird?

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April 13, 2003, 10:09 PM
It's cheaper?

April 13, 2003, 10:13 PM
Most? In my experience, most are arched housings, though you could be right for the newer guns. Problem is, one of the first things to go when customizing is the arched housing. I left mine on as I like it that way. But my Kimber, of course, came with a flat housing, as they are known for providing most of the custom features wanted on the factory guns. I like the flat housings also. I really don't have a preference, though the flat is probably better for concealed carry.

April 13, 2003, 10:16 PM
With my 1911's, I usually group higher with an arched mainspring housing. So I went with the flat ones on all of them.

If you remember, the original 1911 had a flat mainspring housing. The arched version came out with the 1911A1.

April 13, 2003, 10:23 PM
Usually those with large hands prefer flat and those with small hands prefer arched mainspring housings . You could take the arched and form it to fit you. Pick the one that points better for you.

April 14, 2003, 06:22 PM
I am the opposite! I have smaller hands and definitely prefer the flat housing of my Kimber to the arched housings Springfield sold at the time. Much the same as the new Beretta Vertecs. The flat rear frame on the Berettas make it more comfortable and easier for people with smaller hands to control.

April 14, 2003, 10:17 PM
I prefer flat on a carry gun as I shooter better to my point of aim. On a range gun or a play gun, it doesn't really matter. I don't think one is more comfortable for me personally.

IIRC, the primary reason they went from the straight to the arched MSH was raise the point of impact for many soldiers.

April 14, 2003, 11:32 PM
How would the arched MSH raise the point of impact?

I admit, it may be true - both my milspec Springfields shoot high, but my Kimber (flat) shoots where it looks.

April 15, 2003, 12:00 AM
I never fully thought about it. But it was discovered that many (maybe even most, not sure) troops were shooting low with the original flat MSH of the 1911. When changes were put into effect and the 1911A1 was born, one of the changes was to the arched MSH to raise the average POI.

This is from memory from reading years ago so don't flog me too badly if I'm wrong. :p

And I'm not sure if the low POI was from slow aimed fire or from 'just draw the gun, rack the slide and shoot' type shooting. For me, aimed fire doesn't change much but drawing from concealment, taking the safety off and firing, the POI is better with the flat MSH.

April 15, 2003, 05:10 PM
without aligning the sights...holding the gun in one hand...holding your wrist straight (without a break or cocking it downward)...

the arched MSH will cause the barrel to point higher than the same pistol with the flat MSH.

the flat MSH was very popular in "combat shooting" competition. you used to see a boxful of discarded arched housings on most gunsmith's benches. the funny thing is that many folks laud the "fit" of the browning HP and the smith m-39, which both have an arched backstrap.

Sean Smith
April 15, 2003, 05:49 PM
Just personal preference, or whatever the current trend is. I used to like arched, but after shooting a flat MSH gun alot, I like flat better. But I like the curvey backside of a BHP or CZ-75b alot, too. So I dunno. :D

April 15, 2003, 05:55 PM
After WW1 it was found that the arched housing worked better

for the smaller soldiers of the day. Larger hands worked better

with the flat housing. When "combat shooting" became popular

in the 50's 60's and 70's most of the movers and shakers where

big men and everyone wanted what they had. Look at guys like

Elden Carl, Jeff Cooper, Ross Seyfried et. al. they all had/have

large hands.

Today it has become standard for people to expect a flat housing if it is a "custom" or "combat" gun.

April 16, 2003, 02:00 AM
I thought large hands work better w/ arched as it adds more width on the grip?
I like arched myself for competition (grip safety is disabled)because its more hand filling than flat. But for carry, I like flat because its easier to disengage the grip safety w/ it.

April 16, 2003, 02:49 AM
The arched housing arose from complaints that the original 1911 pointed too low. Shooters and soldiers of the time were used to revolvers, not automatic pistols which were still somewhat of a novelty back then.

As for why most 1911s come with flat housing these days, I guess it's simply the perceived demand. Years ago 1911s all came with arched housings and short triggers, and everybody was taking those off and throwing them away. With the current "retro" trend regarding 1911s we seem to be going back to more 1911s with the arched housings and short triggers again.

April 16, 2003, 08:43 AM
The 1911 points low for hip shooting. The arched housing tips the muzzle up a bit, at least it's supposed to.

I've read a lot of people post that the Colt 45 Auto "points naturally" but that's a lot of malarkey in my opinion. Points naturally for a robot, maybe?

Johnny Guest
April 17, 2003, 05:34 PM
I learned to shoot the .45 auto with an arched MSH, during a time when there was a lot of emphasis on one-handed shooting, both from waist level and more-or-less unsighted fire from shoulder level. By the time I tried to use a flat MSH, I probably had a lot of muscle memory working, and I seemed to hit 'way low with it.

I also read of the reasoning behind the switch to arched MSH on the 1911, and this seemed to tally with my experience. As soon as I could afford a Colt National Match (The early "Gold Cup") I got one. As it was conceived as a bullseye patch pistol, it came with a flat MSH. I started switching arched for flat about that time, and have been doing it ever since. Maybe this is the reason I like the old Commanders and Govt Models so much--They came with arched.

Really, I can make do with either one, but prefer arched. In that so many people were making bulleye guns do duty for fighting guns, it became popular to install flat MSHs, first by the gun smiths, and later by the various factories. I believe it is mostly a fad, like "Full Length" guide rods. A matter of personal preference, mostly.


April 17, 2003, 09:14 PM
The 1911 originally had a flat msh; they changed it on the A1 version, since most people were shooting low when point shooting the pistol. The arched msh raised the muzzle of the pistol. Try them both, then change trigger ie: long or short shoe to fit your trigger finger reach.:)

April 18, 2003, 01:15 AM
It's the "in" thing right now.

April 18, 2003, 02:47 AM
I've read a lot of people post that the Colt 45 Auto "points naturally" but that's a lot of malarkey in my opinion. Points naturally for a robot, maybe?

I know what you mean! I think the Luger or the Ruger MKII "points naturally" NOT the Colt .45!

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