1911Tuner
Moderator Emeritus
I picked up a rough but functional '42 Colt a couple weeks back, and decided to turn it into a project for pseudo restoration. Pseudo because it had a gaggle of parts from several USGI contractors, and like I said...it was pretty rough. I could always use another beater.
The slide-to-frame slop wasn't too bad, considering how the gun looked...
so I decided to forego welding and refitting, and opted for swaging. I brought the rails down about .005 inch to remove the vertical play, and since the sideplay was actually pretty good...I decided to squeeze the slide a bit.
Always dreading the malevolent "tink" that looms over every rebuilder...If you squeeze enough of'em, you'll eventually hear it...and because the slide was in very good shape mechanically speaking...I baked it at 200 degrees for an hour before proceeding. ( I REALLY didn't wanna hear it go "tink")
Squeezing just a tiny bit tightened it up nicely, and it required only a little lapping compound and some elbow grease for a smooth, wiggle-free fit to the frame after truing up the frame rails with the files.
Then came the moment that I've been planning for awhile...The Kart E-Z Fit barrel was waiting. I tossed it around and decided to use the old Colt
for the "Kart Trial" instead of going with a full hard-fit. I was curious and had to see what it was all about.
I was initially impressed with the obvious quality of the barrel as it came out of the wrapper. Nicely done, Fred! The chamber was a bit tighter
than I like, with just a tiny bit of taper toward the stop shoulder. Not a big deal, since the finishing reamer would clean it up.
I read the instructions and tossed'em into the can. Not because I didn't feel that I needed to follow the directions, but because the system works with fitting the hood so as to address the #1 lug only in horizontal lockup...
and I like to have at least two lugs bearing in the horizontal plane....so I
cut the fitting pads down just far enough to allow access to the load-bearing frace of the #1 lug, and fitted to the #2 lug by facing #1 back until #2 began to make contact. My gauge suggested that facing back on #2 in hopes of picking up #3 probably wouldn't work out as hoped...so I stopped and decided to go with what I had, and turned my attention to the hood.
I cut the hood until the barrel would press into the slide with light pressure
and returned to the two patented pads in the lug slot. This was where it got tedious, as I wanted a tight vertical lockup, so it was a "One Stroke and Try" exercise. The hood width provided ample side clearance, so no fitting was required there. As it turns out, there's about .004 inch per side,
which is pretty good.
By the time I got the vertical lockup I wanted, the Patented Pads were nearly flush with the slot. This was in part due to swaging the rails down .005 inch, and it worked out nicely with .051 inch of vertical engagement.
I actually had to take a light cut in the #2 slot...maybe .003 inch...to get the barrel to lock smoothly. At this point, I checked the firing pin strike.
It was very nearly dead-center with the original, worn slidestop in the gun.
I fished around and found a new old stock Remington Rand grooved stop
with a .199 diameter pin and tried it. The tight vertical lock returned, so I took another swipe at the fitting pads until the barrel went into battery smoothly and without binding. When I rechecked the firing pin strike, it was centered, and I now had a bit more vertical engagement on the lugs...about .001 inch shy of full depth. Nice!
Back to the hood...I like to see about .003 inch clearance between the hood and breechface in non Match-Grade pistols...but I opted to remove just enough material to get rid of the press-fit. When I dropped a GO gauge into the chamber, it sat dead flush with the face of the hood, and when I checked the gauge with the barrel in the slide, there was zero clearance betwen the rear of the gauge and the breechface. In other words...After fitting the lugs for horizontal engagement, the headspace was dead on SAAMI minimum specs...and actually just a bit tighter. Going strictly by the feel of the GO gauge going into battery, I'd say that the headspace was .897 inch...
I cleaned up the taper in the chamber with the finishing reamer, and rechecked the headspace. Perfect! I was rightly impressed by the close tolerances that kart had held on this particular barrel...and at how well it all came together. Whether or not it would happen again is a matter of conjecture. It did this time, and I was pleased with the results. I decided to go ahead and dress the face of the hood for light contact and stop.
Finally, the barrel bushing had to be fitted to the slide...and even that part went smoothly, and required only lapping compound to fit.
Barrel to slide clearance in linkdown was too tight for comfort...MY comfort anyway,
so i removed a little material from the frame bridge and from the bottom
radius of the barrel behind the lower lug to get a little more. Again...probably due to lowering the rails. When the rails go down, they bring the slide and barrel down a like amount...so I had to compensate.
As it worked out, the barrel is being stopped by the link just slightly in compression, so I clearanced the top of the hole in the link a little, and
freed it up. Linkdown timing was good, and the slide now cleared the barrel by .014 inch a quarter-inch of slide travel.
I had intended to test-fire the gun Monday...but because the initial work went so smoothly...I headed out early today. Function was perfect, and
everything fed...even cast SWCs...and I brought the gun to the bags to
see how it shot.
In a word...WOW! At 10 yards, tossing out the first round with PMC ball, the gun shot into one ragged .650 inch hole about 4 inches high. 25 yards produced a 1.7-inch group that was still a little high. The amazing thing was that the first shot only opened the group about half a bullet diameter
when I shot another group without throwing the first round away. That was small enough to call it a fluke, or blame it on ammo variation.
So...Okay. The Kart E-Z Fit system is all that is claimed. I would have preferred to have had a little extra material in the lower lug feet to work with...but it all came together in magnanimous fashion, and I'm well-satisfied with the results that I got with about 2 hours work involved.
The forumites who are close enough to make the drive can come see the
pistol and shoot it for themselves. No! It's NOT for sale...
The slide-to-frame slop wasn't too bad, considering how the gun looked...
so I decided to forego welding and refitting, and opted for swaging. I brought the rails down about .005 inch to remove the vertical play, and since the sideplay was actually pretty good...I decided to squeeze the slide a bit.
Always dreading the malevolent "tink" that looms over every rebuilder...If you squeeze enough of'em, you'll eventually hear it...and because the slide was in very good shape mechanically speaking...I baked it at 200 degrees for an hour before proceeding. ( I REALLY didn't wanna hear it go "tink")
Squeezing just a tiny bit tightened it up nicely, and it required only a little lapping compound and some elbow grease for a smooth, wiggle-free fit to the frame after truing up the frame rails with the files.
Then came the moment that I've been planning for awhile...The Kart E-Z Fit barrel was waiting. I tossed it around and decided to use the old Colt
for the "Kart Trial" instead of going with a full hard-fit. I was curious and had to see what it was all about.
I was initially impressed with the obvious quality of the barrel as it came out of the wrapper. Nicely done, Fred! The chamber was a bit tighter
than I like, with just a tiny bit of taper toward the stop shoulder. Not a big deal, since the finishing reamer would clean it up.
I read the instructions and tossed'em into the can. Not because I didn't feel that I needed to follow the directions, but because the system works with fitting the hood so as to address the #1 lug only in horizontal lockup...
and I like to have at least two lugs bearing in the horizontal plane....so I
cut the fitting pads down just far enough to allow access to the load-bearing frace of the #1 lug, and fitted to the #2 lug by facing #1 back until #2 began to make contact. My gauge suggested that facing back on #2 in hopes of picking up #3 probably wouldn't work out as hoped...so I stopped and decided to go with what I had, and turned my attention to the hood.
I cut the hood until the barrel would press into the slide with light pressure
and returned to the two patented pads in the lug slot. This was where it got tedious, as I wanted a tight vertical lockup, so it was a "One Stroke and Try" exercise. The hood width provided ample side clearance, so no fitting was required there. As it turns out, there's about .004 inch per side,
which is pretty good.
By the time I got the vertical lockup I wanted, the Patented Pads were nearly flush with the slot. This was in part due to swaging the rails down .005 inch, and it worked out nicely with .051 inch of vertical engagement.
I actually had to take a light cut in the #2 slot...maybe .003 inch...to get the barrel to lock smoothly. At this point, I checked the firing pin strike.
It was very nearly dead-center with the original, worn slidestop in the gun.
I fished around and found a new old stock Remington Rand grooved stop
with a .199 diameter pin and tried it. The tight vertical lock returned, so I took another swipe at the fitting pads until the barrel went into battery smoothly and without binding. When I rechecked the firing pin strike, it was centered, and I now had a bit more vertical engagement on the lugs...about .001 inch shy of full depth. Nice!
Back to the hood...I like to see about .003 inch clearance between the hood and breechface in non Match-Grade pistols...but I opted to remove just enough material to get rid of the press-fit. When I dropped a GO gauge into the chamber, it sat dead flush with the face of the hood, and when I checked the gauge with the barrel in the slide, there was zero clearance betwen the rear of the gauge and the breechface. In other words...After fitting the lugs for horizontal engagement, the headspace was dead on SAAMI minimum specs...and actually just a bit tighter. Going strictly by the feel of the GO gauge going into battery, I'd say that the headspace was .897 inch...
I cleaned up the taper in the chamber with the finishing reamer, and rechecked the headspace. Perfect! I was rightly impressed by the close tolerances that kart had held on this particular barrel...and at how well it all came together. Whether or not it would happen again is a matter of conjecture. It did this time, and I was pleased with the results. I decided to go ahead and dress the face of the hood for light contact and stop.
Finally, the barrel bushing had to be fitted to the slide...and even that part went smoothly, and required only lapping compound to fit.
Barrel to slide clearance in linkdown was too tight for comfort...MY comfort anyway,
so i removed a little material from the frame bridge and from the bottom
radius of the barrel behind the lower lug to get a little more. Again...probably due to lowering the rails. When the rails go down, they bring the slide and barrel down a like amount...so I had to compensate.
As it worked out, the barrel is being stopped by the link just slightly in compression, so I clearanced the top of the hole in the link a little, and
freed it up. Linkdown timing was good, and the slide now cleared the barrel by .014 inch a quarter-inch of slide travel.
I had intended to test-fire the gun Monday...but because the initial work went so smoothly...I headed out early today. Function was perfect, and
everything fed...even cast SWCs...and I brought the gun to the bags to
see how it shot.
In a word...WOW! At 10 yards, tossing out the first round with PMC ball, the gun shot into one ragged .650 inch hole about 4 inches high. 25 yards produced a 1.7-inch group that was still a little high. The amazing thing was that the first shot only opened the group about half a bullet diameter
when I shot another group without throwing the first round away. That was small enough to call it a fluke, or blame it on ammo variation.
So...Okay. The Kart E-Z Fit system is all that is claimed. I would have preferred to have had a little extra material in the lower lug feet to work with...but it all came together in magnanimous fashion, and I'm well-satisfied with the results that I got with about 2 hours work involved.
The forumites who are close enough to make the drive can come see the
pistol and shoot it for themselves. No! It's NOT for sale...
)
