A while ago I mentioned again my take on the “hard fit” combat 1911. To sum up, a lot of competition style hard fight 1911s from back in the day were not reliable because of that fit. Dyspeptic Gunsmith left a lengthy comment with his take on the matter you can read below.

Here’s the irony about 1911’s and accuracy:

It was due to a fanatical mis-understanding about what really contributed to accuracy on the 1911 that got us hard-fit 1911’s – with their attending reputation for unreliability. The 1911, as originally designed, and originally produced, was quite reliable. I’ve shot old military 1911’s from WWII issue dates (owned by vets of WWII) which had some wear on them, and with 230 grain ball, they never failed to go “bang.” Ever. These men reported to me that they kept their pistols clean, but that they were in plenty of sand (in the PTO) and their 1911’s always went “bang” when they needed them, which was often enough that carrying a 1911 wasn’t for show.

Then, as you point out, in the 1980’s, the quest for super-tight groups started. Let’s back up and look at where this zeal started.

In 1961, S&W started the S&W Model 52 program. The spec for that pistol (which shot .38 Special 148-grain wadcutters) was for the pistol to hold a 5-round group from a machine rest at 50 yards of 2″ or less. If the group was larger than 2″, the pistol went back to the S&W gunsmiths until it passed this accuracy requirement.

If you look around at most pistol accuracy group measurements, you see that they were shot at 25 yards. At 50 yards, the accuracy of the 1911/1911A1 in 1940 was called out to be a “mean radius” at 50 yards of 1.36″, with the 1911 shot off a “muzzle rest.” Kuhnhausen’s books on the 1911 call out accuracy of “moderately loose” 1911’s at 50 yards to be 5″ to 6″ with GI ammo, with some “maximum specification” tolerances (ie, max allowed looseness) as shooting 8 to 10″ groups at 50 yards.

Come the 1970’s, we started to see all manner of approaches to tighten the 1911. One of the best from the factory was the Series 70 Colt “Collet bushing” and barrel. The secret to making a 1911 accurate is to keep the muzzle end of the barrel locked up with the slide (which has the sights on it) when in full battery. The Colt collet bushing did that quite nicely. Some gun rag writers harped on the supposed reliability problems of the collet bushing, but the inconvenient truth was that most collet bushings that broke off a leg were due to how the owner was disassembling his gun, rather than the collet breaking during firing. The collet bushing tightened up groups considerably.

Then came the tapered barrels and fitted bushings. Then gunsmiths started looking for “more” slop to take out, and then things started becoming iffy in the reliability department. We started seeing work done in the link, in the barrel lock-up into the slide. When people had finished welding up and re-fitting barrels to slides, they started messing with the slide fit onto the frame. It was at this point that competition 1911’s started developing real issues in reliability.

As for what will give you the most improvement with the least compromise on reliability? Snugging up the barrel bushing and then the fit of the barrel to the bushing. Or going with the Series 70 collet bushing and barrel. Next is the link and fit of the chamber area to the slide. Making the slide tight on the frame? The accuracy improvement of that work is much less than the first two, and IMO, makes the 1911 very finicky.

2 Comments

  1. Wild, wild west's avatar Wild, wild west says:

    When a bullseye pistol shooter puts his gun box on the table there is a reason why one of the first things to come out of the box is a little bottle of lube.

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  2. Dyspeptic Gunsmith's avatar Dyspeptic Gunsmith says:

    I will add the following additional information on my assertion about locking up the muzzle end of the barrel being the most important issue:

    Our host had a recent post about the H&K Mk23 pistol chosen by SOCOM in the 90’s. Well, what I said about securing the muzzle end of the barrel of 1911’s as a way to gain the most precision for the least impact on reliability of the 1911 is also true in the Mk23/USP pistols.

    H&K solved their issue of taking “slop” out of the muzzle fit by use of an O-ring. Here’s H&K’s owner’s manual for the pistol:

    Click to access Mark-23-Operators-Manual-5-26-21.pdf

    Please see p. 33, Fig. 15 to see what I’m talking about. To get an idea of how thick the O-ring is, please see p. 22, Fig. 12. It isn’t much.

    A buddy owned one of these (the USP civilian version) in the 90’s, and it was a pretty darned accurate pistol. Off the bags, we could get it to group 2″ at 25 yards. That’s still half of what the S&W Model 52 will do, but it was up there with tightened 1911’s – for the cost of an O-ring.

    In the big scheme of things, this seems intellectually offensive to gun owners and even gunsmiths. But from an engineering perspective, it was brilliant – it worked, the cost to add the groove to the barrel was trivial, and the cost of the O-ring was also trivial. Further, if the O-ring was lost or wore out in combat, it would only degrade the precision of the pistol, not result in an inoperative weapon.

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