Well, I intended to follow the directions to the letter this time... I really did, but when my handy-dandy gauges revealed that if I had just cut the hood until the barrel fit into the slide, the #2 lug would have been the only player in the recoil game... so I cut the pads down a bit and started alternating between the face of the hood and the face of the #2 lug until I got the barrel into the slide a little ways.
Nope... I didn't use the 40-dollar tool kit that has to be ordered separately. I already had everything that I needed, so why spend the bucks?
Setting the face of the lug back about .004 inch brought #1 into the game, leaving #3 kissing about .002 inch of air... but I can live with that until the gun sees a couple thousand or so rounds and hopefully starts to pick up #3.
I turned my attention to the fitting pads and wound up with .038 inch of engagement depth with a tight vertical lockup. Firing pin ding is well- centered. Linkdown timing was good, but the barrel didn't clear the slide bridge quite as much as I like, so I took .003 inch off both the frame bridge and the lower radius of the barrel to get more.
I had just a touch of stem bind as the pistol fed, so I turned my attention to the throat and ramp. The leading edge of the barrel throat didn't quite make the requisite .032-inch gap at the top of the ramp, so I hit it a couple of file strokes and re-cut the throat. I scraped the top corner a bit to help with the stem bind, and all was well.
The bushing was a little too tight in the slide for a simple lap-to-fit, so I drove over to John's and borrowed his mandrel... since I can't find mine yet... and used the lathe to remove .002 inch off the bushing OD with a file. Final fit was done with 5 micron lap, followed by straight J&B bore cleaner. Curiosity being one of my weaknesses, I also checked the fit with the MGW bushing that had been in the slide. The ID was almost an exact match for the Kart supplied bushing... so I decided to try'em both when the gun goes to the proving ground.
The link... The link was like the other one on the barrel that I fitted to the GI Colt. The slidestop pinhole was oversized at .208 inch. I figured that the other one was a fluke... one that had slipped past QC, but now I see that there's a purpose behind it...though I'm havin' a hard time figgerin' out exactly what that purpose would be. Anybody able to shed some light on why an otherwise excellent barrel would come in with what is essentially an out-of- spec link? Enlighten me! A Wilson #3, lightly relieved in the top of the hole to get the barrel off the link as it cammed up into the slide worked out nicely. The barrel didn't lock on the link... just rode it around the forward radius of the lug.
Checking the headspace revealed that the barrel was slightly short-chambered at .595 inch from the breechface, so I dropped a finishing reamer in it, and set the final depth at minimum (.898) just for chuckles, since I have hopes that the locking lugs will set back a couple thousandths over time and increase the headspace a like amount. If I see any reliability problems when the gun gets dirty, I'll sink it another .003 inch deeper. Tight headpace is good for accuracy... sometimes not so good for dead reliability when the chamber gets canked up and hot. I'll forego a half-inch tighter group at 25 yards to get reliable return to battery any old time. Ain't all that freakish over pistol accuracy anyhoo.
Final hood to breechface fit was set at .002 inch and it'll open up another thou or two with a use. 3-5 thou strikes a good balance between tight fit and dirt tolerance... and ya'll just know how anal I am over reliable. Any problems within 2,000 rounds dirty and things will immediately be made looser across the board... Count on it.
Did the standard clearance check between the barrel and the extractor and test-fired 7 rounds. Function looks good so far. May take a teeeeensy bit of tension off the extractor at some point... just because. Accuracy and reliability testing will likely have to wait a couple weeks. I start some back on some meds that make me a little too shaky to shoot... but I should be acclimated to'em well enough by the end of the month to make a range run.
Still impressed with the overall quality of the barrel and the fitting system. Not real happy with that link hole thing though... There's just GOTTA be a logical reason for it.
Stand by... This may take a while. If I don't get squared away until this thread gets buried, I'll start another one.
Decided to start the med regimen later this A.M. and jump on into the reliability test phase. Lit out for the range at 9 with 36 magazines loaded up. 252 rounds later, with a 5 minute cool-off at the halfway point yielded zero malfunctions. The gun was too hot to hold, so I let it have a break to prevent any damage. I didn't dunk it in the water though...
No pure accuracy testing was done, and all rounds were fired at the 8-inch falling plate machine at 10 yards at the rate of approximately one round every 2 seconds. I killed many plates, which made up in part for my dismal shootin' Friday when kartracer went with me. Just one of them dang days, Joe...
Ammo was PMC hardball from a 2-case lot that I'd had stored for 3 years and broke it out around daylight in honor of the occasion. The rest of it will go through the gun between now and the end of August... hopefully well before. We'll see. Accuracy testing will be done with the last 50 rounds, and an additional accuracy/reliability testing will be done with a variety of factory hardball and hollowpoint ammo at the conclusion of the 2,000 round settling-in procedure. Cleaning/re-oiling will be performed at 500-round intervals.
Thanks for the report Tuner, sounds like that ol' gun is shooting well.
The barrel transplant bidness sure is booming. Revived another old Springer, huh? How many rounds did this one have in its past? With you rebuilding 'em every 20-30,000 rounds there's no need to buy a new one.
It's the GI Mil-Spec that I tried to destroy last year. Everything was upgraded with good parts except the 2-piece barrel. Nothin' wrong with it really... it just bothered me, so when I chose between that one and the NRM Colt to try another Kart E-Zee fit barrel in... the Springer got the nod. The Colt already has a decent barrel.
So far, the accuracy looks good on the plates... as near as I can tell with the "Old Eyes" syndrome and those little-bitty sights. The sandbags will tell the tale though.