1911 lower lug question

[Justinmac13]

I cut the lower barrel lugs on a schuemann hybrid barrel and I have good lock up but the slide has some rearward movement after lock up,  the barrel is still locked up tight but the slide, barrel and all moves on the frame slightly,   Did I cut the barrel lugs too far back?  It just doesn't make sense because if that was causing the issue the slide moving backwards on the frame is moving away from the back of the lugs.

Edited November 15, 2017 by Justinmac13
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[drewbeck]

If the slide is moving backwards then you are unlocking the action..??..and the barrel should be going down because of the link.

 

it sounds like you need a recoil spring to hold it in battery and ease your mind 

[drewbeck]

But if you need a spring to hold it in lockup your flats are too short or cut too steep.  

 

My experience is that the recoil spring helps more to gauge whether the fit of the hood/lower lug is correct during unlocking vs lockup because at least for me it’s always been easier to get the gun to “lockup like a vault” vs getting the timing right so it locks up tight then unlocks smoothly and that the slide clears the barrel hood and that the hood length/shape is correct for unlocking.

 

the biggest factor in consistency in my experience for lock/unlock is how much vertical play you have in the slide/frame fit.  Every .001 of clearance vertically makes the lower lug fit that much more critical, challenging, and nearly impossible to make it reliable and accurate.

 

I’m not a paid GS but I’ve fit a few and this has been my experience as I’ve gotten better measuring tools to really understand what’s going on but it sounds like the flat is too short on your lower lug cut

[ACree]

Think of what is happening from the point of the forward lock-up position. The locked slide/barrel cannot move any farther forward because of the contact of the SS to the lower barrel lug. Therefore, being over cut is not an issue as long at the lower lug is making contact with the SS. Mark the slide stop and check. Assuming that is fine, the amount of flat that you have on the lower lug will allow the slide/barrel to move rearward the distance of that flat while remaining in lock-up. Once that distance is covered, the link takes over and begins to pull the barrel downward, unlocking the barrel from the slide. That delay over the flat is a desired condition.

 

 

[ltdmstr]

SOP is to cut the lugs just to the point where the thumb safety moves up into the relief on the slide.  As CCG stated, the flat on the bottom lugs is a good thing.  And because of the flat, the slide moves back a bit before the barrel starts to cam down on the link.  That's normal.

[Justinmac13]

Thank you guys   I was hoping I had not messed it up     I didn't do a very good job cutting the lower lugs as they were not perfectly parallel, I am currently only getting contact on one leg but lock up is still too tight. I'm hoping when that high spot gets removed it contacts both legs 

[ACree]

Thank you guys   I was hoping I had not messed it up     I didn't do a very good job cutting the lower lugs as they were not perfectly parallel, I am currently only getting contact on one leg but lock up is still too tight. I'm hoping when that high spot gets removed it contacts both legs 

Is the barrel clocking from any contact with the sides of the hood? What is causing only the one leg to make contact?

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[drewbeck]

Ya make sure the hood has clearance on all sides, and be damn sure the barrel isn’t springing before you do the finish cleanup of the lower lug.

 

you can check for springing by putting the barrel in the slide, turn it upside down and gently tap the lower lug with a ball pein hammer. If it “tings/rings” when tapped it’s springing and you need to figure out where and relieve the barrel likely near the muzzle. If it “clunks” when tapped you’re good to go.

 

if you trim the lower lug but the barrel is springing you’ll get a vertical string shot pattern when you test fire it. At that point you’ll fix the springing and then have to weld and recut the lower lugs correctly.....been there, done that

[Justinmac13]

The fit is tight and does not spring, it took a lot of sanding on the bottom front of the barrel and about an inch back on the top, this being a hybrid barrel I wasn't sure where the contact points would be.  I will have to pay close attention next time to if it looks like it is clocking the barrel   That's a good point     Thx  I will look.

[drewbeck]

I’ve not fit a hybrid but I’d imagine any clocking of the barrel would be a nightmare with clearances around the “island”, it should be super easy to tell though with feeler gauges during the full action of the slide which is not as easy to check on traditional barrels.


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