When I started shooting NRA "Bullseye" ( now called "NRA Precision Pistol") a couple of years ago, my interest in 1911 Gunsmithing shifted primarily to accuracy. I still enjoy building custom guns, but Ive spent a lot of time reading and discussing barrel installation and have put countless rounds down range from a Ransom rest, fitting and re-fitting barrels, welding and machining frame rails, all in the quest for accuracy from a handgun.
I Thought I would share some pics of the tools and techniques I use. Everyone does it differently, this is only my process, and it is subject to change any moment, but I know there are some other ODT tinkerers who fit their own barrels and might enjoy seeing how someone else does it. I posted some of these pics in another forum as a review of the Weigand fixture, but I thought I would just do a overview of the process here.
I use Kart barrels and EGW bushings. EGW also makes some great tools, Like the hood length gauge. Without the EGW tool, its difficult to accurately measure the slide for the needed hood length of the barrel, EGW makes it easy.
Next step is measure the opening in the slide for the hood at the breach face. I use calipers then verify with gauge pins.
Once Ive got the slide and barrel measurements, I figure out how much metal to remove from either side of the hood to make sure it fits perfectly in the slide and stays centered in the frame. I shim the lower lugs centered in the frame and use the Z axis display on the Mill to take this measurement. This one is critical, and the mill will measure to .0002"
Once everything is blueprinted, I can make the cuts. I use a Jack Weigand barrel fitting fixture for the mill cuts on the hood and lower lugs. It was an expensive tool, but for me, worth every penny.
First level and indicate the barrel in the fixture
Then make the cuts
If all the measurements worked out, the barrel will fit into the slide with a slight press fit. We are looking for less than .001" hood to breach face and about .001" on either side. After the first few rounds are fired, it will seat itself with a friction free fit.
Now its on to the upper lugs. The idea here is to fit the upper lugs with .040"- .050" engagement. The firing pin hole should line roughly up with the center of the primer hole in an chambered empty case. I shoot for .045" with even contact (using transfer ink). Ive heard of some people setting upper lug engagement based solely on centering the firing pin on the primer. While its nice to get a perfect firing pin strike, this can be a dangerous path to follow. Chasing after a centered primer strike can lead to serious timing issues and battered/ peened lugs and frame. Proper lug engagement is key, the firing pin will be close if all else is correct.
Now its time to fit the bushing. Im a huge fan of EGW angle bore bushings. Send them the measurements of your barrel and slide and you get a bushing set for the perfect 1 degree angle of lock up.
With the bushing installed and the barrel fixed in battery in the slide, I use a Wilson lug cutter with a undersize cutter. This will make the initial cut on the lugs level with the slide stop pin holes in the frame.
Then I use gauge pins to verify how much more material needs to be removed at the mill.
The end result are lower lugs cut with an .080" flat, cut at a 1 deg. angle of lockup. An appropriate link is installed and the barrel timing is checked.
Here are the marks left on the slide stop pin after a few rounds
I Thought I would share some pics of the tools and techniques I use. Everyone does it differently, this is only my process, and it is subject to change any moment, but I know there are some other ODT tinkerers who fit their own barrels and might enjoy seeing how someone else does it. I posted some of these pics in another forum as a review of the Weigand fixture, but I thought I would just do a overview of the process here.
I use Kart barrels and EGW bushings. EGW also makes some great tools, Like the hood length gauge. Without the EGW tool, its difficult to accurately measure the slide for the needed hood length of the barrel, EGW makes it easy.
Next step is measure the opening in the slide for the hood at the breach face. I use calipers then verify with gauge pins.
Once Ive got the slide and barrel measurements, I figure out how much metal to remove from either side of the hood to make sure it fits perfectly in the slide and stays centered in the frame. I shim the lower lugs centered in the frame and use the Z axis display on the Mill to take this measurement. This one is critical, and the mill will measure to .0002"
Once everything is blueprinted, I can make the cuts. I use a Jack Weigand barrel fitting fixture for the mill cuts on the hood and lower lugs. It was an expensive tool, but for me, worth every penny.
First level and indicate the barrel in the fixture
Then make the cuts
If all the measurements worked out, the barrel will fit into the slide with a slight press fit. We are looking for less than .001" hood to breach face and about .001" on either side. After the first few rounds are fired, it will seat itself with a friction free fit.
Now its on to the upper lugs. The idea here is to fit the upper lugs with .040"- .050" engagement. The firing pin hole should line roughly up with the center of the primer hole in an chambered empty case. I shoot for .045" with even contact (using transfer ink). Ive heard of some people setting upper lug engagement based solely on centering the firing pin on the primer. While its nice to get a perfect firing pin strike, this can be a dangerous path to follow. Chasing after a centered primer strike can lead to serious timing issues and battered/ peened lugs and frame. Proper lug engagement is key, the firing pin will be close if all else is correct.
Now its time to fit the bushing. Im a huge fan of EGW angle bore bushings. Send them the measurements of your barrel and slide and you get a bushing set for the perfect 1 degree angle of lock up.
With the bushing installed and the barrel fixed in battery in the slide, I use a Wilson lug cutter with a undersize cutter. This will make the initial cut on the lugs level with the slide stop pin holes in the frame.
Then I use gauge pins to verify how much more material needs to be removed at the mill.
The end result are lower lugs cut with an .080" flat, cut at a 1 deg. angle of lockup. An appropriate link is installed and the barrel timing is checked.
Here are the marks left on the slide stop pin after a few rounds