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Can anyone explain how 'tight' the bushing can fit to the muzzle of the barrel before reliability is impaired ?

I'm new to the 1911 world, and was curious how tight the fit can be before it is "too-tight" to allow consistent cycling of the mechanism.

Thanks for educating another 'newbie' ! --CC
 

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I was just reading the instructions that came with the last EGW bushing I bought. They recommend .0005"-.001" clearance between barrel and bushing, with the barrel diameter reduced an additional .003" behind the lock-up area. The instructions that come with the Kart EZ Fit barrel suggest that most "tight" bushings are fitted too tight, springing the barrel and degrading accuracy.
 

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You have to watch those EGW guys


couple things.

the lenght of the bearing surface.
Lets say a barrel locks up at 3/4 of a degree and there is zero play between the barrel and bushing cold and not locked up. You can trig out how much room you need to have to allow the barrel to lock up without flexing the barrel like Kart is speaking of. You need to know how long the contact area is?

The barrel heats up faster than the bushing and Grows as it heats up. If you were working very close the gun may not go back into battery or drag on the barrel.

Most barrels are relieved after the first 1/4 to 1/2" to save wear and tear on the bushing.

Huning built a gun for Bill Rogers, at a bianchi Cup in late 80's (in pratice he would shoot 48 round strings and the gun was fine.) On the plates back than you shot till you missed, his gun started getting pretty hot and it stopped dead. (trick gun with a bearing bushing in the front, ironically a Huning design) We took the gun apart and it seemed fine, put it back together and it worked from there on fine.

Huning desingned the angle bore bushing some time after that. the bushing is bored on an angle (about the angle of lock up) and the bottom is relieved so the barrel travels back and fourth freely. When it is locked up the bore tightens up but if correct does not bind or flex the barrel.

So on a std. bushing you need more room or relief to allow the barrel to lock up. On the briley bushing you need a little more room, probably .001 to allow the barrel to grow and not bind. on the angle bore you can run closer as it is only tight when locked up.

hope this helps

geo ><>
head janitor EGW
 
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