1911 Question - Bushing to Barrel Clearance?

sixty9santa

sixty9santa

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Hi all,

I'm in the process of customizing my Norinco M1911A1-C. I'd like the beast to accurate but also be a realiable combat ready machine. So I have learned a lot from this board and I now know that the barrel bushing makes a somewhat of a difference when it comes to accuracy. Now I have a bushing I.D. of .587" and a barrel O.D. of .580", is an .007" difference that much?
Isn't that much needed for heat expansion?
So pretty much I'd like to know what the minimal clearance should be between the barrel bushing and the actual barrel itself yet still be combat ready?
 
.... I don't know enough to get into the specific dimensions needed for clearances with a Norinco. I can categorically state ,that really tight clearances reduce reliability. Accuracy vs reliability, is a thin edge. My suggestion , would be to try what you have and see how things work out. Usually, it's best to try one "improvement" at a time and see how it functions.... cosmetics aside ! ...... David K.
 
Along with barrel bushing fit you want to check how good a barrel lockup you have.

With an empty gun pull the slide back and forth a couple of times. With the slide fully forward push down on the barrel at the breach face. The less movement the better. The more movement you have can be reduced with a longer barrel link.

You also want as little play between the slide and the frame. This can be reduced with some careful peening and squeezing of the slide.

Reducing the barrel to bushing fit is only one of the steps to making a 1911 more accurate. All of these steps will make the gun more accurate but also less reliable.
 
Much thanks to the above, I have already tightened the frame and slide within .003" and I have yet to check lock up.
 
Well in my new Kimber which is the tightest pistol I've ever owned (don't know exact numbers but the bushing for instance is on tight!). says in the manual to clean it every 100-150rnds, I imagine it'll work like clockwerk but like anything with tight tolerances once debris, etc. starts to accumulate it'll slow down then eventually stop.

If it's good enough for LA SWAT, it's good enough for me ;)
 
sixty9santa said:
Anyone?
Someone must know since a lot of members get match bushings on thier pieces.
Click to expand...
.007" is much more than is required for heat expansion. High end guns like Ed Brown and Les Baer, as well as customized target guns, generally have a bushing-barrel clearance of .001-.002" tops.
 
Yep, Capp's right. Should only be .001-.003 inches for match-grade accuracy. The thing is, the barrel and the bushing will wear into each other over the course of, say, 300 rounds, so it only gets looser with use. This is normal. Don't expect full reliability until after the 300th round.

One of the easiest ways to get there is to just purchase a Wilson drop-in match barrel and bushing. Not as cheap, but a lot easier than honing out a bushing to match the barrel. Also, don't forget that the bushing-to-slide fit should be tight enough that it is all you can do to remove the bushing with finger pressure. Some prefer it so tight that you have to use a wrench for installation and removal.

-Bob
 
Zims is right..001 is the Match clearance. If the bushing is properly fitted to slide and - relieved - to avoid barrel spring back, reliable functioning should be achieved with .001 of clearance total.
 
No idea on tightness, but then the M1911 was designed for one thing, to kill people. It does that very well. It was never intended to be a target pistol and as stated, tightening things up can lead to unreliability. Saw a perfect example of that at a CCW class. One guy had a tricked out one that failed to cycle properly, so he failed the live fire test. And yes, I know that lots of folks use them in competition. Most of which would be rather difficult to carry every day.

Oh by the way, thats only my opinion.
 
John Sukey said:
No idea on tightness, but then the M1911 was designed for one thing, to kill people. It does that very well. It was never intended to be a target pistol and as stated, tightening things up can lead to unreliability. Saw a perfect example of that at a CCW class. One guy had a tricked out one that failed to cycle properly, so he failed the live fire test. And yes, I know that lots of folks use them in competition. Most of which would be rather difficult to carry every day.

Oh by the way, thats only my opinion.
Click to expand...
I don't think anyone is suggesting using a tricked out pistol for CCW. In Canada, CCW is not an issue for most. And while the 1911 may not have been designed with target shooting in mind, it clearly does quite well in that department – it wouldn't be dominating Camp Perry Nationals if that wasn’t the case.

And while it’s true that tighter guns are generally much less reliable than milspec Colts, reliability is not of crucial importance for bullseye shooting.
 
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