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Discussion Starter #1
I was testing my new KimberEclipse using this information. The rear area of the lower barrel lugs do not ( have never ) touched the horizontal filed area in the frame, but contact is shown on the vertical area between barrel and frame. IT APPEARS, from the burnishing of the slide stop rod, that the rear travel of the barrel is being stopped by the mating of the slide stop's rod with the matched curved area in the barrel's lower lugs, but not by the link - this situation seems to differ from the problem described below, but I am still not sure if this is correct or not ...

Thanks for the assistance



-------------------------------------------------------------------------------- http://www.schuemann.com/
Scheumann Barrel Timing Tests ...
Possible problem number two is created if the impact surface in the frame, that the barrel's lower lugs hit, is too far rearward. This changes the above description in the following way.
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As the slide and barrel move rearward, the link rotates about the slide stop pin and starts pulling the barrel down, thereby unlocking the barrel from the slide. After the barrel is completely unlocked from the slide, the barrel continues moving downward and rearward, and has its vertical motion stopped when the bottom of the barrel hits the top of the frame. The link then stops the barrel's rearward motion before the barrel's lower lugs can contact the impact surface because the impact surface is too far rearward in the frame. The link is not designed to stop the rearward motion of the barrel, and the extra stress will eventually break the link
 

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Discussion Starter #2
I just retested my barrel - what I stated about the lug wear was from the Forward travel not reverse. And, the barrel seats both vertically and rearwards into the frame and I can install the frame stop without problems - I think I did not perform the test correctly
 

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Discussion Starter #3
I did some more tests - the slide pin wear is from Forward travel. The barrel can be set into the frame aft and down, and the slide pin easily installed - I am not sure I performed the test correctly. It appears that, even though the test showed problems, I am not loading the link in rearward travel.

Regards !
 

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The barrel lower lugs, forward of the link pin, should not contact the slide stop pin, either coming or going. If the vertical surface in the frame is too far forward, the barrel will hit it prematurely. If it prevents the barrel from fully seating on the frame, the slide could rub the barrel as it cycles; if there was actual interference between the slide and barrel, it could damage the upper lugs. When the barrel is completely linked-down, is it free of the slide at the top? I think Schuemann likes .015" of static clearance. If you're using a standard-length link, the slide is not rubbing on the barrel as it cycles, and there is evidence that the barrel is stopping on the vertical surface in the frame, then the timing/fit seem to be OK. Are you having problems that lead you to believe something isn't right?
 

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Discussion Starter #5
Hello Rick,
I am more just trying to 'learn the 1911' and was a bit shocked when the marker did not show that the rear vertical surface of the barrel lugs and the frame were touching !! Subsequent tests with a thin piece of aluminum tape showed there was proper contact - the magic marker just did not 'rub off' by pressure contact.

The gun shoots well, lets hope my experiments do not degrade it too much <laugh>

So far, the polishing up of the action group
has yielded a nice result

( the sear-hammer interface is still stock )

Thanks,

[This message has been edited by SouthGun (edited 09-04-2001).]
 

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If you really want to get working knowlege of the 1911,get Kuhnhausen's books and study them.While it won't make you a pro 'smith,it will give you a great understanding of the works and the interrelationship of the parts.I don't have experience with Kimbers,but alot of base grade (even Colts)1911s stop barrel linkdown on top of the frame bridge,with the link stopping rearward movement.It isn't the right way,but it was the 'original' way.
 

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Kuhnhausen's first book says the barrel should stop on the top of the frames - not so much that it "should", but that it will. In the second volume, he reprints Schuemann's barrel timing/fit info, and says the barrel should stop on the vertical surface. I suspect it was not possible to build G.I. pistols with sufficiently close tolerances to guarantee the barrel would stop in the ideal manner. FWIW, my Delta Elite and Detonics Combat Master both stop on the vertical surface, as they came from the factory. I have "fitted" (then why is it called pre-fit?) a Schuemann barrel in that manner to my M1911A1, and it is still going strong. I think Dane Burns posted here, that he fits his barrels for more of a corner contact fit, with the junction of the tube/lugs contacting the shoulder of the frame, rather than full contact between the rear of the lugs and the vertical face of the frame.
 

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Great clarification Rick.I agree with Danes? philosophy.I feel the top .125+/- plus a slight top of frame bridge is optimal.Too much of the verticle stop (especially too low) stresses the lug,too much bridge stresses the link.
 
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