View Full Version : Series 70 Gov. Model .45

December 30, 2004, 10:54 AM
I'm posting this question here because I feel sure that most 'smiths will
deal with more Series 70's than even the most avid 1911 "shooter".

The question is this: What is the long-term evaluation consensus of the
"collet" barrel bushing in the original Series 70 guns. I've read in several
places that the prongs were prone to break, thereby disabling the gun.

I'm shooting a Series 70 I bought in 1973, with the original barrel and
bushing. It has between four and five thousand rounds through it, and
still hold a pretty good group (if the operator cooperates), and is a very
reliable piece.

But: Since I do occasionally carry it for personal defense, should I
consider changing out the barrel and bushing? If so, what to? Colt
match barrel, Wilson, etc. ?

December 30, 2004, 11:36 AM
In a 1911 colt 5000 rounds is around the break in period,
I have a 70 gold cup with way over 10,000 rounds and never had a problem.
You have a part that has lasted and worked well, I would trust it more than one that wasnt matched to the gun and had only 50 rounds in it.
If your concerned have it checked for cracks and even wear by a good smith and if he says theres no problem leave it alone.

December 30, 2004, 03:50 PM
I'd have to lean the other way on this one. A solid bushing, properly fitted, will give you the same or better accuracy and won't be as likely to fail. Colt invented that collet bushing to get better accuracy out of guns without having to fit a bushing to the barrel and slide. It was a shortcut, and the downside was that the collet can break, possibly rendering the gun useless. A good smith can fit a match bushing for very little money. You can do it yourself if you are willing to learn how. It is a good way to learn a bit about your pistol.


Geoff Timm
December 30, 2004, 04:26 PM
I've had one for many years, as advised I never remove the bushing from the barrel.

Rounds? Unknown. I didn't count when the Army was giving away ammo back in the 1970s. And I ran Dillion for many years.

Who still thinks about putting in a solid bushing. :cool:

December 30, 2004, 05:35 PM
I always thought that the collet bushing problems were caused by poor QC rather than an inherent collet problem.

James K
December 31, 2004, 03:35 PM
There have been reports of collet bushings breaking on their own, but the ones I personally know about broke because the gun owner could not resist trying to beat on the collets to "tighten up" the pistol. Still, I generally advise replacement of the collet bushing if the gun is to be used for any serious purposes. Otherwise, leave it alone unless it breaks.


Dave Sample
December 31, 2004, 06:46 PM
No 1911 ever left my shop with a collet bushing left in it. I have seen a half a dozen or more fail. I had to beat them apart with my lead hammers and it was no fun to watch. Yours will never fail, of course.

January 6, 2005, 12:06 PM
i picked up a beater of a colt series 70 nickle about 15 years ago at a pawn shop in miami. actually traded a glock 19 even for it. since then i have probably put 2000 rounds through it and the collet bushing is still fine. just checked it as a matter of fact to make sure. no cracks, yet. maybe next decade.

January 7, 2005, 01:06 PM
My understanding is, you'll either get one that will break, or one that won't. That is, the concept is not unsound, but it depends on the execution, and plenty of the Colts were not held to tight enough tolerances. If you got a "good one", it would work just as advertised and last. If you got a bad one, it will break. If I'd put 5000 trouble-free rounds through it, I'd figure I had a good one. If I was going to carry the gun, I might go ahead and invest in $40s' peace of mind and get a solid bushing, though. The EGW angle bore bushing has all but dropped in to a few of my Colts, and they are a very nice part.

January 15, 2005, 11:21 PM
... it looks like there is no "Consensus" on the collet bushing.

That pretty much fits with my mindset about the whole thing.
I have known there was a "possible" problem with them for a long time.
But I knew mine was working well, so I just didn't do anything about it.

Much like the problem (and RECALL) of the early Smith 686's, some
problem with the hole in the firing-pin bushing being too large.
I think it was something about primer blowback causing the cylinder to
lock up. Anyway, I never got that looked at, either. And my 686
still shoots every time.

Maybe I'll get around to getting a solid bushing on that Colt one of
these days. Thanks for all your responses. I really appreciate your


January 16, 2005, 08:48 AM

I also have a mk4 70 series I bought new in 1073. It's been pretty much a safe queen. Haven't shot it in 25 years. I guess with all this talk, I need to pick up a replacement busing for it. Anyone know where I can get one and approx. prices, please?



Dave Sample
January 17, 2005, 03:37 PM
Brownell's is the place to get these parts. Metal "Work Hardens" and the more it flexes, the closer it is to self destruction. The question that I have is not whether it will fail, but when. It's a bad part. Period. I could be wrong about this, but I would rather not have to tell a widow that I left it in the gun and her husband died becuase of a part I deem bad and was too lazy to replace. Mr Murphy is alive and well and I have a great deal of respect for him. If your 1911 is a Toy, then we have no problem here. If you bet your life on it, then it's a different matter. Good Luck!

January 17, 2005, 05:38 PM

Thanks to Dave Sample for the Brownelle's suggestion.

However, I cna't find one on their web site.

Any other places to pick one up?


January 17, 2005, 06:09 PM
I just typed "1911 bushing" on the Brownell's search engine and many came up.

MidwayUSA should have a selection, as well.

January 17, 2005, 08:05 PM
Thanks, Handy!

I checked Brownells and Midway-no joy for collet bushing for MK IV 70 Series

Any other thoughts will be appreciated.



January 17, 2005, 08:38 PM
I don't think anyone realized you wanted to replace the crappy collet bushing with another crappy collet bushing.

Colt is the only company that makes these horrid things. Brownell's does carry Colt parts, but you might as well just go to Colt.

For good bushings, the sites above are good sources. :)

Dave Sample
January 18, 2005, 02:24 PM
I gave away a dozen of these and I don't think I have any more of them. They are bad news and you need a solid bushing for a replacement. The only ones I have around here now have broken fingers so I can use them for Show and Tell.

Harry Bonar
January 18, 2005, 02:27 PM
Dear Sir:
For combat, or heavy use where you must not have a collet bushing. At NOVAKS 45 SHOP we do not use collet bushings due to the chance of "tying up a 45."
I don't doubt that they work, and some forever, but I myself always fit a match bushing to any 45. I think about 30% of your accuracy comes from a good front bushing fit.
You can do this yourself if you take time. The bushing should be lapped in the slide and then the bbl fit and lapped in by operating slide (after initial bbl. fitting).
Of course, accuracy also comes from a good bottom lug fit with the slide stop pin (in battery there should be NO bbl down-play) and the bbl. should never be fit on the lengt of the link to remove this; you really need to fit a new bbl.
Hope this hekps - put a properly fit solid link!

January 20, 2005, 06:55 PM

I was just looking for an extra couple of collet bushings for my MK IV 70 Series.
I don't NEED any, as I mentioned, mine is a safe queen-not been shot in 20+ years. I really only wanted some as it was mentioned here that they are prone to breakage, and I thought it would be a good idea to have a few, in case. Also, I would like to keep it in original config for value reasons.

Thanks for the replies. This is a great place for newbies and old timers like myself.

January 24, 2005, 10:36 PM
I ordered a "drop-in" Ed Brown bushing from Midway, about $19.
I mic'ed my barrel O.D., and my bushing O.D., and the specs on his
drop-in unit are within .002 of my parts, on the "go" side.
If it needs a little fitting I have some one who can do that, and if it
gets me reasonable accuracy, I'll be satisfied. About the best I have
ever gotten from the gun was "reasonable" accuracy, anyway.

Thanks for all your input.


Dave Sample
January 24, 2005, 10:52 PM
Good Man , Walter. I consider that money well spent!

January 25, 2005, 09:22 AM
Dave , you are confusing "work hardening" and "fatigue failure" .If the failure is quick it's a problem of poor heat treatment usually and if failure takes a while it's a fatigue failure which is more likely to be poor dimentions .