Building a GI Spec 1911

Even the original GI 1911s required hand fitting. Using a mix of original parts, frame, slide, and barrel, you can pretty much count on having to tweak something to make it fit and function smoothly and properly. The result will still be "USGI spec", though.

In order to tighten the slide to frame fit you will have to peen the rails on the slide, not for the amature (it requires expensive gauges to maintain the proper engagement). The grip sarety could require some fitting, but withthe Kunhausen books you could probably do thet yourself. Teh barrel to slide fit is critical, and requires an expert machienist that is familiar with the proceedure.

Other fitting tasks would only require a set of good stones and copious patience.

Good Luck

Al Minyard

Even the original GI 1911s required hand fitting. Using a mix of original parts, frame, slide, and barrel, you can pretty much count on having to tweak something to make it fit and function smoothly and properly.

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Nope. Sorry. That's a myth, especially if the subject is WW2-era pistols.

The engineers at Colt and Springfield Arsenal put on their thinkin' caps and revamped many of the dimensions and tolerances in order to develop a set of standardized gauges for nearly every part on the gun so that any part from any gun built to spec by anybody could be drop-in interchangeable...and it worked.

Testing was done by disassembling 2 randomly selected pistols from each of the five contractors...tossing them in a big box and stirring well...and assembling 10 pistols without regard to which part was original to which pistol. The criteria was that all 10 pistols had to meet requirements as to fit, function, and accuracy. The pistols were then dissassembled and reassembled again. All passed.

If all parts are truly within spec...an ordnance-spec pistol can be assembled and expected to work. The problem today is in finding genuine USGI components that aren't part of a rejected lot. Sometimes the lot was rejected for something as simple as color or finish...and sometimes it was because they weren't dimensionally within spec. Sometimes an out of spec part can be massaged to make it work...and sometimes it can't.

Whenever you find a gun show vendor selling "Genuine" USGI parts...Caveat Emptor applies in full force. It may well be a GI contract part...but it may also be out of spec.

How easy would it be to build a GI spec 1911 using all original GI parts?

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As a thought exercise (not that there's anything wrong with that), or an actual project? The actual assembly isn't that difficult. Your biggest hurdle would be finding actual GI parts. Modern production parts, especially from different vendors, are not necessarily GI spec.

In order to tighten the slide to frame fit you will have to peen the rails on the slide ...

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That wasn't done on GI guns. Even for target guns, the gain in accuracy is small (but when a quarter or half inch at 50 yards can win or lose a match, it is still important), much less so than fitting the barrel to the slide.

aminyard:

The barrel to slide fit is critical, and requires an expert machinist that is familiar with the procedure.

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Well...If you're chasing half-inch groups at 50 yards, the barrel fit is critical...but not so much in an ordnance-spec pistol.

I have an unaltered original/correct USGI Colt that was built in the spring of 1919...one of the last ones that the Army took. With an older lot of PMC hardball...the real GI -spec PMC...it'll hold to about 3.5 inches from the bags at 50 yards if somebody with better eyes than mine shoots it. With my cast 200 grain SWCs and 4 grains of Bullseye...it'll cut a 10-shot group that'll go under 3 inches...and there's nothing hand-fitted in the gun, much less precisely fitted.

Slide to frame fit on this old Colt is very good, with just enogh play that you can feel it if the gun is dry...but with oil in the rails, there's virtually no detectable movement. This is as it should be.

And here it is:

Next is a 14-shot 25-yard sandbagged group from a badly worn Norinco after I peened the rails a little at the front to reduce vertical play in order to get a better vertical barrel engagement...and a Kart Easy-Fit barrel that took all of an hour to install...with hand tools.

The pistol belongs to a member on another board. This is the picture that he sent to me the day after he fired the group.

The ammunition was a new lot of PMC hardball, and there was no tossing out first-round flyers. One magazine was fired empty, and another locked in. 14 shots with arguably not the most accurate ammunition on the shelf.

While truley original, unissued GI parts are interchangable, it is unlikely that you will find them. A poorly fit barrel can make a 1911 dangerous (here I am talking about the barrel to shroud fit. This is not a project for an untrained individual to do.

Good Luck

FWIW, Springfield sells a GI 1911 that might be close enough to the real deal to make you happy.

A poorly fit barrel can make a 1911 dangerous (here I am talking about the barrel to shroud fit.

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Barrel hood? Why?

Here's a layman who chronicled his year long project to build his own 1911. It's pretty interesting.

http://how-i-did-it.org/1911-project/index.html

While truley original, unissued GI parts are interchangable, it is unlikely that you will find them.

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What he said!

Real unaltered GI 1911 parts that are not rejects are about as rare as dodo birds anymore.

My stash from my late 60's military service is about gone, and I'm here to tell you there are few to none out there to replace them with that I can find.

rc