Evolution Gun Works 1911 Barrel Bushings

[1911usmc]

I recently decided to try a pre-fit EGW 1911 Barrel Bushing on the recommendation of a few friends.

The way it works is you measure the O.D. of the lock up point of the barrel and the I.D. of the slide. You provide these measurements when you order the bushing. The bushing that I ordered is angle bored for just the lockup measurement. It is already machined for the link down cycle.

When I received the part it fit nice and tight on the barrel in the link up stage and moved freely as the slide cycled.

My only concern is the bushing is not as snug as I would like in the slide. I have fit many match bushings that move snugly but freely in the slide.
I am guessing that it may be necessary to give a slightly larger measurement for the I.D of the slide to get the fit I am looking for.

The overall result was the barrel fit exactly the way I was looking for, and the slide to bushing fit was about five times tighter than stock fit.

My question is: Has anyone had similar results ot is this an isolated incident??

[shafferds]

Measurements are only half the battle it also has to do with the feel of the fit to the barrel and slide. A match fit is just that not just two numbers. You can get close but more than just out side and inside diameter.

[dwalker]

the barrel bushing is only part of it, the lug and chamber fit is a huge factor in barrel lock-up.

What kind of gun are working with?

[craneman]

Nothing is perfectly round either. I guarantee the cut in the end of your slide is not round and neither is the bushing. It probably has less than .001" run-out, but it is not round. If the run-out is in different spots in relation to one another, you could easily introduce .001 extra clearance overall and both measure the same

You can feel play with a .001" slip fit on a bearing surface that small and narrow. For no play you are shooting for .0005" slip fit or tighter. If you need a bushing wrench you are starting to distort the bushing and/or spread the slide ever so slightly. Temperature differences from one location to another can effect measurements that small. There is a myriad of things that can cause differences when you start getting smaller than .0005".

If I wanted that perfect of a fit I would order it .002" oversize on the OD and hand fit the final. So IMHO un-professional opinion, yes order slightly oversize.

[MosinVirus]

Every time I ordered form EGW the bushingS came very tight. When I measure diameters, I measure in different locations. For example, with calipers in the slide I will turn the slide and try to find the largest ID reading.

With barrel, same thing. Caliper on the barrel, turn the barrel and see if the reading changes. It shouldn't but hey, it might.

[1911usmc]

Thank you all for your comments and advice. This work is on a new Colt 1911 government model. The stock barrel is being reused to establish a baseline for accuracy. There appears to be approximately .055 lug engagement, and close but not tight breach face to hood clearance.

Thank you again, and all further commetts would be appreciated.

[MosinVirus]

Wow, .055" lug engagement seems a bit excessive. What size link are you using?

[pklin1297]

If it's a new Colt .45, chances are the bottom lugs aren't riding on the slide stop pin either... Equal contact between those surfaces will help the accuracy quite a bit. 0.055 upper lug engagement is a lot...

So far with the fusion and Brazos' slides I've used, I've been able to just order the "Drop In" .580 ID, .699 OD bushings. The OD always required fitting as the ID of the slide has always been .698 consistently, and depending on the barrel, the bushing ID may need some adjustments as well. Being able to buy the "Drop In" set (bushing and monogram spring plug set) every time certainly saves the headache of measuring the slide and barrel, then wait for the bushing to be made.

To get max accuracy benefit, fit a Kart barrel to that Colt.