Collet barrel bushings

[dsk]

L- standard solid bushing, R- Colt collet bushing

I often see threads started asking about so-called "collet" barrel bushings, usually in reference to Colt pistols. The collet bushing was first used by Colt in 1970. The last batch of standard commercial Governments used the barrel bushing and matching barrel (which has a slightly belled muzzle) as a test run, then it was formally introduced with the Series 70 models in 1971. The spring fingers of the bushing grip the belled end of the barrel during lockup to tighten the fit and improve accuracy. For the most part it worked great, as the accuracy of my own box-stock Series 70 attests. It was basically a production means of improving out-of-the-box accuracy without going through the expense of hand-fitting standard bushings to every pistol Colt made.

The bushing remained in use until a few years into production of the Series 80, around 1988 or so. The reason for it being discontinued and the conventional "solid" bushing reinstated was due to a few isolated reports of problems with the bushing. During manufacture of the pistols the matter of varying production tolerances was always an issue. If the slide ID was machined too large the fingers wouldn't grip the barrel well, and accuracy would be lackluster. If the slide ID was too small then the fingers would have no room to swell, causing them to flex and buckle. After repeated use these fingers would then break, causing the broken piece to flop around inside the weapon until it jammed up inside somewhere, often tying up the pistol while it was still loaded. Gunsmiths weren't usually too happy to receive a loaded Colt that was jammed up in this fashion, especially given the fact that correcting it usually involved putting the pistol in a vice, taking a mallet and banging the slide back and forth until things came loose. It wasn't healthy for the gun's finish, and it wasn't healthy for the gunsmith either if there was still a round in the chamber.

There are many owners who say they've already put thousands of rounds down the tube without experiencing a broken bushing. Odds are they won't, because by now it's probably evident whether or not there's an issue with tolerances in their particular weapon. It's just that one in a thousand that may end up breaking. But that is why I usually tell people to replace the collet bushing with a solid one anyway just to be on the safe side. Your pistol will probably never have a problem, but the fact is you really never know when it'll fail. It may a long time before the fingers finally succumb to fatigue and break off. Maybe after 5,000 rounds, maybe after 50,000. I've kept the one in mine simply because it's more a safe queen than a shooter, but if it were being used for competition or defense I'd replace the bushing with a standard solid unit.

And yes, to answer another frequently-asked question, a standard non-oversize solid bushing will work on an early Series 70 or 80 pistol. The belled muzzle on a Series 70 barrel is still the same outside diameter as a conventional "straight" barrel, so a factory Colt solid bushing should drop in without fitting. Aftermarket oversized units (Wilson, Brown, etc.) will of course require gunsmith fitting to the slide and barrel as with any other type of 1911 pistol.

The only factory pistols you're likely to see them in are Colt's Government Models and Gold Cups made from 1970 through 1988. Commander and Officers ACP models never used the bushing nor did any of the so-called "clone" makers, although I am aware of some aftermarket companies (such as Bar-Sto) who offered collet bushings for Commander-sized pistols for a short time during the 1970's.