Barrel link vs. Lower Barrel Lugs - 1911Forum
1911Forum
Advertise Here
Forum   Reviews   Rules   Legal   Site Supporters & Donations   Advertise


Go Back   1911Forum > >

Notices


Reply
 
Thread Tools Display Modes
  #1  
Old 03-19-2020, 01:43 PM
Dan13 Dan13 is offline
Member
 
Join Date: Sep 2019
Posts: 97
Barrel link vs. Lower Barrel Lugs

I have read several times the slide stop pin is supposed to ride on the lower barrel lug feet rather than just the barrel link. I got a NOS USGI chrome lined barrel from 1979 and also a brand new #3 (.278") barrel link and when assembled the link hole the slide stop rides in is proud of the lower barrel lug feet by about .005" or so. Is there definitive documentation the slide stop pin rides on the lower lug feet? The new link I got is marked 3. It is odd two parts made to specs would not line up. If so, I assume I cannot simply egg out the link hole to allow the slide stop pin to correct this(?) Would a #2 link be the solution?
Reply With Quote
  #2  
Old 03-19-2020, 03:19 PM
log man log man is offline
Senior Member
 
Join Date: Feb 2007
Location: Riverside County, CA
Posts: 14,145
Quote:
Originally Posted by Dan13 View Post
I have read several times the slide stop pin is supposed to ride on the lower barrel lug feet rather than just the barrel link. I got a NOS USGI chrome lined barrel from 1979 and also a brand new #3 (.278") barrel link and when assembled the link hole the slide stop rides in is proud of the lower barrel lug feet by about .005" or so. Is there definitive documentation the slide stop pin rides on the lower lug feet? The new link I got is marked 3. It is odd two parts made to specs would not line up. If so, I assume I cannot simply egg out the link hole to allow the slide stop pin to correct this(?) Would a #2 link be the solution?
USGI is drop in for the most part and riding the link is common for that. For a better fit where the lower lug does sit on the slide stop pin a quality gunsmith fit GS barrel is when you can fit for this added accuracy. Many factory built 1911's ride the link as supplied.

LOG
__________________
Warning, do not remove any material from your pistol or any of it's parts if you do not know the result and it's consequences! .......it gun....gun dangerous...Email: [email protected]

Reply With Quote
  #3  
Old 03-19-2020, 03:37 PM
BBBBill BBBBill is offline
Senior Member
 
Join Date: Mar 2000
Location: Alabama and Florida, US
Posts: 11,151
^^^ What log mans said. You are talking apples and oranges with GI fit vs gunsmith fit. GI fit obviously works, but you will never get best performance from the gun with that. Just depends on you wants/needs/wallet.
Reply With Quote
Sponsored Links
Advertisement
 
  #4  
Old 03-19-2020, 04:25 PM
david_root2000 david_root2000 is offline
Member
 
Join Date: Apr 2018
Age: 59
Posts: 787
A lot of discussion about this link and barrel thing. Why don't you just spring for the $6.00 part and try it?

It will not go as far into battery and will link down earlier ?

A .200 slide stop pin will help with lug engagement.

So you might loose .005" with the shorter link, and gain .0015-.003" from the larger slide stop pin.

As I said earlier, I am not a gunsmith.

I put a .005" larger slide stop pin in a bull barrel commander. I ended up needing a longer link. In the end, I went from 5" groups at 25 yards to 1.5 ish.

IN a properly fit barrel, the slide stop pin should ride on the feet and keep the upper lugs fully engaged.

Log Man Knows his stuff. I am just a hack.

David

Last edited by david_root2000; 03-19-2020 at 04:28 PM.
Reply With Quote
  #5  
Old 03-19-2020, 05:38 PM
Dan13 Dan13 is offline
Member
 
Join Date: Sep 2019
Posts: 97
Thanks all for the replies. My question is more of original design intent. Was it designed to ride the link and some smart gunsmith discovered increased accuracy if you could get the slide stop pin to get more support from the lug feet? Or, is this a case where parts are purposely produced out of spec to allow fitting? Or, was it designed to only be supported by the link? Any documented definitive answer?

Last edited by Dan13; 03-19-2020 at 05:44 PM.
Reply With Quote
  #6  
Old 03-19-2020, 09:40 PM
log man log man is offline
Senior Member
 
Join Date: Feb 2007
Location: Riverside County, CA
Posts: 14,145
Quote:
Originally Posted by Dan13 View Post
Thanks all for the replies. My question is more of original design intent. Was it designed to ride the link and some smart gunsmith discovered increased accuracy if you could get the slide stop pin to get more support from the lug feet? Or, is this a case where parts are purposely produced out of spec to allow fitting? Or, was it designed to only be supported by the link? Any documented definitive answer?
Pages of argument have been written about this. The patent document seems to favor riding the link. Regardless the patent was sold to Colt to do as it wished, and production dictated the the careful fitting required for a barrel to stop with the upper lugs and ride on the lower lug not be followed. In fact the Colt drawings of the barrel are clear that the upper lug recess will allow well over .050" of engagement, as much as .056", but .040"-.045" is the depth of the first lug recess cut of a GS fit barrel, which then limits the engagement, so fitting the lower lug to hold the barrel up against the slide lug holds the barrel firmly in battery. The 1911 was designed, or produced, by Colt so a bucket of parts could be assembled and work. Over 100 years later many alterations and improvements have been made.

LOG
__________________
Warning, do not remove any material from your pistol or any of it's parts if you do not know the result and it's consequences! .......it gun....gun dangerous...Email: [email protected]

Reply With Quote
  #7  
Old 03-19-2020, 10:10 PM
megafiddle megafiddle is offline
Member
 
Join Date: Oct 2019
Posts: 358
The old 1911 ordnance specs also show that the barrel would ride on the link for parts at mid spec.

niemi24s over at m1911.org did extensive work on determining this.

-
Reply With Quote
  #8  
Old 03-19-2020, 10:32 PM
James's Avatar
James James is offline
Awesome
 
Join Date: Jan 2001
Location: Southeast
Posts: 2,829
If better fit/accuracy was my goal, rather than buy an oversized slide stop and tinker around with less than ideal or "bargain" parts..I would buy a "gunsmith fit" barrel and properly fit it.

If I simply wanted to use a barrel I got cheap, I would make sure the barrel was linked into proper position/engagement with the slide and would not worry about how close the feet rode the slide stop to get there.

I definitely wouldn't arbitrarily shorten the link or egg out the hole...both of those potentially create less than acceptable lug engagement. No matter what I did I would verify lug engagement depth before firing the gun. Just swapping those parts and trying them is not ideal.
Reply With Quote
  #9  
Old 03-20-2020, 06:24 AM
passx passx is offline
Member
 
Join Date: Mar 2017
Location: NW Indiana
Posts: 1,268
So it’s interesting that this thread has come about as I’ve been working on a similar issue.

Late last year I bought a Kimber long slide 6” target gun where the slide stop pin was around .195in and the frame was at about .199in with the barrel link at I believe .205 with light contact on the barrel lugs. I ended up ordering an EGW oversized slide stop, changing the barrel link with one that is the same length but a smaller hole that gave me a clearance to the pin of just slightly over .001in , I also reamed the frame holes slightly to provide a .0005in clearance to the pin.

This gave my Kimber much more consistent accuracy with tighter groupings .


Now I just bought a new Baer Thunder Ranch Special and cleaned it yesterday and measured everything, I found it had a .200in stop pin and the frame holes had about .0006in clearance, not bad. But the link hole has 012in clearance to the stop pin, I was shocked it was this loose on a “custom” gun.

Now I’ll add that it is obviously riding the barrels ramp because the black oxide shows wear marks on the ramp lugs and is a pretty even marking on both ramp lugs.

Is this something that I should either send the gun back for or I was thinking of doing the same thing I did with my Kimber and change the link with a same length link with a smaller hole to match the pin. This is a 1.5” garantee gun that I’ve only put 300 rds through. When I shot it I was a bit disappointed as it seems to not group as well as I had hoped, some of it is the grips are a bit small for my tastes which I think contributed to the variation, plus the shooter wasn’t at his best either.

So what are the opinions on the excessive (my opinion) pin to link Clearance ? Send it back, fix it or just shoot it and enjoy it ?

Last edited by passx; 03-20-2020 at 06:27 AM.
Reply With Quote
  #10  
Old 03-20-2020, 08:00 AM
Dan13 Dan13 is offline
Member
 
Join Date: Sep 2019
Posts: 97
Ok, thanks all - I learned something! So original design was for the "dreaded" link rider I have read so much wringing of hands about, but the "desired" consensus is for better accuracy the SS pin should engage the barrel lug feet. So, if my barrel is currently unlocking fine and passes that test using a stock USGI barrel and a Wilson Combat #3 stock spec link, so the SS pin is riding .005" or so above the barrel lug feet (link rider) - that is per original design. If that is the case, and I wanted improved accuracy, I can see no fear of changing timing or engagement by installing a #2 link to drop the SS pin that .005" to contact the barrel lugs, then replace my Wilson Combat SS which is .197" with an EGW pin measuring .201 or so to put the barrel lugs back up to slide lugs in lockup - I get better accuracy without really changing any specs or timing - correct?

James, can I measure lug engagement by measuring the exposed slide lug surface showing through the space between top of barrel hood and underside of slide during lockup, then subtract that measurement from the total lug measurment with the slide off the pistol?
Reply With Quote
  #11  
Old 03-20-2020, 09:34 AM
log man log man is offline
Senior Member
 
Join Date: Feb 2007
Location: Riverside County, CA
Posts: 14,145
Quote:
Originally Posted by Dan13 View Post
Ok, thanks all - I learned something! So original design was for the "dreaded" link rider I have read so much wringing of hands about, but the "desired" consensus is for better accuracy the SS pin should engage the barrel lug feet. So, if my barrel is currently unlocking fine and passes that test using a stock USGI barrel and a Wilson Combat #3 stock spec link, so the SS pin is riding .005" or so above the barrel lug feet (link rider) - that is per original design. If that is the case, and I wanted improved accuracy, I can see no fear of changing timing or engagement by installing a #2 link to drop the SS pin that .005" to contact the barrel lugs, then replace my Wilson Combat SS which is .197" with an EGW pin measuring .201 or so to put the barrel lugs back up to slide lugs in lockup - I get better accuracy without really changing any specs or timing - correct?

James, can I measure lug engagement by measuring the exposed slide lug surface showing through the space between top of barrel hood and underside of slide during lockup, then subtract that measurement from the total lug measurment with the slide off the pistol?
Realize a GS fit barrel's first upper lug recess cut is .040"-.045"so it can not go higher and then the lower lug is cut to hold the barrel up on the slide stop pin with the upper lug in contact. You can clearly see this is the case with pictures of GS fit barrels. This picture shows a new Kart GS fit barrel below and the lug cuts clearly show this.
Attached Thumbnails
IMG_0702.JPG  
__________________
Warning, do not remove any material from your pistol or any of it's parts if you do not know the result and it's consequences! .......it gun....gun dangerous...Email: [email protected]

Reply With Quote
  #12  
Old 03-20-2020, 10:06 AM
James's Avatar
James James is offline
Awesome
 
Join Date: Jan 2001
Location: Southeast
Posts: 2,829
Dan, I am not sure I understand your proposed method of measuring as typed. I use a caliper and with the pistol fully assembled and in battery measure from the top of the ejection port to the top of the barrel along the centerline. I then take a feeler gauge that I have (about the thickness of two credit cards) open the slide slightly, stick the tool between the rear barrel hood and breechface, and allow the slide to close on that. This will wedge the barrel hood up against the bottom of the slide lugs and then I measure from the same place top of ejection port top of barrel again. The difference is your engagement.

I am thinking through the link change though, if you use a shorter link and a wider diameter slide stop, how does the wider slide stop raise the barrel back up? The link is measured from center to center of the holes and the hole in the link would still be centered on the wider slide stop pin.
Reply With Quote
  #13  
Old 03-20-2020, 10:12 AM
log man log man is offline
Senior Member
 
Join Date: Feb 2007
Location: Riverside County, CA
Posts: 14,145
Quote:
Originally Posted by passx View Post
So itís interesting that this thread has come about as Iíve been working on a similar issue.

Late last year I bought a Kimber long slide 6Ē target gun where the slide stop pin was around .195in and the frame was at about .199in with the barrel link at I believe .205 with light contact on the barrel lugs. I ended up ordering an EGW oversized slide stop, changing the barrel link with one that is the same length but a smaller hole that gave me a clearance to the pin of just slightly over .001in , I also reamed the frame holes slightly to provide a .0005in clearance to the pin.

This gave my Kimber much more consistent accuracy with tighter groupings .


Now I just bought a new Baer Thunder Ranch Special and cleaned it yesterday and measured everything, I found it had a .200in stop pin and the frame holes had about .0006in clearance, not bad. But the link hole has 012in clearance to the stop pin, I was shocked it was this loose on a ďcustomĒ gun.

Now Iíll add that it is obviously riding the barrels ramp because the black oxide shows wear marks on the ramp lugs and is a pretty even marking on both ramp lugs.

Is this something that I should either send the gun back for or I was thinking of doing the same thing I did with my Kimber and change the link with a same length link with a smaller hole to match the pin. This is a 1.5Ē garantee gun that Iíve only put 300 rds through. When I shot it I was a bit disappointed as it seems to not group as well as I had hoped, some of it is the grips are a bit small for my tastes which I think contributed to the variation, plus the shooter wasnít at his best either.

So what are the opinions on the excessive (my opinion) pin to link Clearance ? Send it back, fix it or just shoot it and enjoy it ?
The link hole for the slide stop pin is larger for a very important reason. The barrel link goes past center at battery of nearly .050", then when it is fired the barrel and slide have moved back together nearly .100", this without pulling the barrel down at all is why there is this clearance. The barrel links down during the rest of the travel of .150" for the total of .250" from battery to link down.

LOG
__________________
Warning, do not remove any material from your pistol or any of it's parts if you do not know the result and it's consequences! .......it gun....gun dangerous...Email: [email protected]

Reply With Quote
  #14  
Old 03-20-2020, 12:44 PM
Magnumite Magnumite is online now
Senior Member
 
Join Date: Sep 2001
Location: Belcamp, Maryland, USA
Posts: 7,972
Not only what log said, but a .005” shorter link and a .004” diameter pin is going to pull the barrel away from the VIS. If no lower lug contact is made with the VIS and attendant broken links and damage barrel and slide lugs could result.

One poster mentioned one change will affect multiple dimensions. It is very true when changing any barrel fit parameter.
__________________
The modern production 1911 - high visibility sights, beavertail grip safety, aluminum trigger, good trigger pull, enhanced slide/ frame fit, accurized barrel/bushing fit. If itís not a Kimber, itís a copy.
Reply With Quote
  #15  
Old 03-20-2020, 04:30 PM
BBBBill BBBBill is offline
Senior Member
 
Join Date: Mar 2000
Location: Alabama and Florida, US
Posts: 11,151
Quote:
Originally Posted by passx View Post
Ö

I found it had a .200in stop pin and the frame holes had about .0006in clearance, not bad. But the link hole has 012in clearance to the stop pin, I was shocked it was this loose on a ďcustomĒ gun.

Now Iíll add that it is obviously riding the barrels ramp because the black oxide shows wear marks on the ramp lugs and is a pretty even marking on both ramp lugs.

Is this something that I should either send the gun back for or I was thinking of doing the same thing I did with my Kimber and change the link with a same length link with a smaller hole to match the pin. This is a 1.5Ē garantee gun that Iíve only put 300 rds through. When I shot it I was a bit disappointed as it seems to not group as well as I had hopedÖ
VVVVV

Quote:
Originally Posted by log man View Post
The link hole for the slide stop pin is larger for a very important reason Ö
LOG
^^^^^

First, and not to be contrarian, but Les Baer guns are not custom and lots of folks have had issues with their guns. Not to say that they cannot be a good gun, but shortcuts are taken to produce the gun at that price point. I suspect that you have discovered one of those shortcuts.

As Log notes, the link hole must be larger, however a standard link pin hole is .2045"-.2055" which is larger enough to allow for the .100" dwell time in lockup that most strive to get. Someone hogged yours out while fitting. I don't know how Baer fits his barrels (maybe with a longer flat to keep it in battery a bit longer), but that link is abnormally large. Kart provides an oval link hole on their EZ/Xact fit barrels for a similar reason. I never use them as they are not needed by the time I get through fitting.
Reply With Quote
  #16  
Old 03-20-2020, 05:36 PM
passx passx is offline
Member
 
Join Date: Mar 2017
Location: NW Indiana
Posts: 1,268
Ok log/bill, I guess I wonít worry about it, what I was thinking though was to fit the same length link but with a smaller pin hole, guess Iíll leave well enough alone. The sloppiness just surprised me a bit because otherwise this thing is very tightly fit.

It came with the test target which meets their 1 1/2Ē garantee but I couldnít do it justice as the small grips moved around in my hands a bit, when I could hold onto it, it did group well.
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 01:59 PM.


NOTICE TO USERS OF THIS SITE: By continuing to use this site, you certify that you have read and agree to abide by the Legal Terms of Use. All information, data, text or other materials ("Content") posted to this site by any users are the sole responsibility of those users. 1911Forum does not guarantee the accuracy, integrity, or quality of such Content.

Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
Search Engine Optimisation provided by DragonByte SEO (Lite) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.
Copyright 2015 1911Forum.com, LLC. All Rights Reserved