1911 Barrel Bushing Questions

B

BOFD

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What I am trying to figure out is the different types of barrel bushings that are available for different 1911 calibers.
Some things that I’d like to clear up are as follows:

• Are different bushing sizes required for each different caliber (I.D / O.D.)?
• Can bushings be fit with simple tools such as a drill, jeweler files and emery cloth?
• What does a Match Bushing do for you if you still have to fit it?
• Are all Barrel Bushings created equal between manufacturers?

Thanks in advance….
 
A match bushing is going to give you a tight fit between the bushing and slide, and also between the barrel and bushing. It is intended to take any slop in those areas out, and increase accuracy with the consistency gained.

You can fit one with a minimum of tools, but I would not recommend it. I double wouldn't recommend it if you haven't fitted one before with the guidance of a gunsmith.

The last couple I have used were GI NM bushings. Maybe I forget too easily but it seems like they needed a lot more work than a Brown or an EGW.
 
They are "match" because they are oversized and require fitting. Stock bushings are drop in because they fit looser to work in a variety of guns.
 
1) Colt has used a number of different barrel diameters in their .38 Supers, but most .45 have similar dimensions. Barrel OD is ~.580", and slide ID is ~.700". "Match" bushings are undersized on the ID, and oversized on the OD, so they can be fitted to the individual gun, which may vary a few .001's in either direction. You will find "drop-in match bushings" that are slightly tighter than a Mil-Spec part, splitting the difference between Mil-Spec and fitted. The Commander has approx the same ID and OD dimensions as a Government Model, but the skirt of the bushing is shorter, so it won't interfere with the barrel lugs when cycling. The Colt Officers ACP used a bushing specific to that gun, so bushings intended for the OACP will fit nothing else.
2) The easiest to fit bushing is the EGW angle bore. It requires less fitting than a standard bushing, with similar results. I've fitted them with little more than a strip of emery cloth.
3) Your answere is in your question; because you have to fit it, you get the best possible fit, and therefore, the best accuracy.
4) No. Some are cast, some are MIM, some are forged, and some are barstock. They may all look about the same, but the manufacturing process will determine the accuracy of the dimensions, and the strength/durability of the part. I wouldn't buy a bushing that wasn't fully machined from a forging or barstock.
If you measure your barrel OD, and your slide ID, then take up the Brownells wish book, you may find a drop-in bushing that fits within .001"-.002" of what you want. I've had very good experiences with the EGW drop-in angle bore, in both Colt and Springfield pistols, getting a very nice fit, with little work. A standard bushing is bored concentric to the slide bore, and requires relieving to allow the barrel to swing up into battery. The amount and location of material removed to allow this movement is critical. The angle bore bushing is bored at the critical lock-up angle, and then requires only the non-critical relieving necessary to allow smooth cycling of the slide.
 
I would say Rick pretty well nailed it for you. I also agree with what Rick said on the manufacturing process, buy a good forged or barstock bushing.
I use National match bushings and fit them on the lathe. You can fit a bushing by hand but the lathe will control the tolerances more accurately.
Fit the outside of your barrel bushing .001 smaller then the inside measurement of the slide; the inside of the barrel bushing should be angle bored .0015 larger then the outside measurement of the barrel diameter.
Regards
Bob Hunter
www.huntercustoms.com
 
Thanks Guys

I got exactly the information I was looking for.
This forum is really great!!

Again Thanks
 
I just installed a EGW angle bore on my GI. Very easy. As Rick said, I used emery cloth and then bore lapped it with JB paste and gun oil.

Accuracy improved immediately. It also looks sharp. I also like how it extends beyond the barrel to protect the crown. :)

egw_3.jpg
 
Evolution Gun Works (EGW) are the experts on 1911 barrel bushings. I used to live down the street from EGW when they were at their previous location. They used to work on my guns back when they still did gunsmithing and when the built complete guns. Their President, George Smith is a preeminent expert on 1911's, and just an all around great guy to talk to on this subject;

http://www.egwguns.com/bushing-faq
 
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Today, if you provide the ID and OD, EGW will make a bushing to those dimensions for you.
I've always been happy with their "drop-in", but you can eke out the best accuracy if you get the dimensions down to within .001".
 
"...but the manufacturing process will determine the accuracy of the dimensions..."

First, the dimensions of the bushing cannot be determined by the maker of bushings. A given bushing has to mate with a given slide and a given barrel, so bushing makers make their product oversize in O.D. and undersize in I.D. so it can be fitted to both the slide and the barrel. Normal factory bushings, barrels and slides are made to tolerances that ensure the parts will fit together without any special care, but that means the parts can have "slop" and the gun will not be as accurate as it could be with fitted parts.

Second, the manufacturing process has almost nothing to do with the dimensional accuracy of the product since both cast and forged bushings (and other parts) have to be finish machined; only MIM parts can be used "out of the mould" with no machining.

In my limited experience, the biggest mistake made by DIY bushing fitters is the failure to realize that the barrel of many pistols drops at the rear to unlock and the bushing has to be made to allow the barrel to do that freely.

Jim
 
In my limited experience, the biggest mistake made by DIY bushing fitters is the failure to realize that the barrel of many pistols drops at the rear to unlock and the bushing has to be made to allow the barrel to do that freely.
Click to expand...

That's why they should be angle bored, angle boring the barrel bushing allows the barrel to move into and out of lock up without causing barrel springing.
 
True, but I have seen "match bushings" that were not bored at an angle; that was to be done by the fitter and was sometimes overlooked. The result was poor function and even bent barrels.

Just for fun, ask 1911 fans why the bushing is there in the first place, and most will say it is due to the genius of JMB to make the pistol more accurate. Most will also say that the BHP has no bushing. But the real reason for it is to fill the hole in the slide needed for the tools to cut the breech face and the locking lugs. And the BHP does have a bushing, it is simply fixed in place as part of a permanent assembly and is not removable.

Jim
 
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