Barrel Fittically Correct.( In case anybody was wonderin'.)
Note:
Although I wracked my brain in the effort to remember all the details of this saga as best I could, some of the dimensions and procedures given may not be entirely accurate...but they're close. After nearly 40 years, the little things tend to get a bit fuzzy.
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I arrived at the shop two weeks after I started on my journey to truth and wisdom, a wiser but apprehensive lad. Having learned my lessons via the long, hard route...I was duly chastised, and today was the day that I would do this barrel thing for keeps. It was a brightening, nearly sunny Saturday morning...0500 hours. Henry figured that I'd need to get an early start. He was right.
Uncle H opened a package that contained a match-grade barrel, still covered with the odd-smelling oil that had been there for many years. Void of proof marks, this wasn't a Schuemann or a Kart or a Storm Lake. This one would be worth mucho dinero if it hadn't been opened that Saturday.
All critical dimensions were oversized for hand-fitting...and the chamber was semi-finished.
Short reamed by .015 inch so that the final headspace could be chosen by the armorer. A true hard-fit barrel. I was scared.
The first step was to gauge the slide for lug locations and record them. The measurements were done 3 times, and an average of the three taken for a final fit dimension. Likewise for the barrel, from hood to front lug faces. This barrel was to be fitted to pistol #2...since the first barrel was dead in the water. It was a 1944 production Remington Rand.
Henry told me that the process would be a bit different this time, since the second thrust face in the slide was located a bit too far to the rear. I wouldn't start with the hood this time. I would start with the #2 barrel lug.
Checking the final measurements determined that I would have to cut the face of the #2 barrel lug back by about .003 inch in order to bring #1 into contact. This cut must be made straight and true, and no more than .0005 inch out of square. That's a half-thousandth of an inch. If you had a sheet of steel that thin, you could probably read through it. It was to be one stroke of the file and measure...repeat, until the dimension was reached.
Lug #1 was within reach...On to lug #3. That one was now almost .005 inch off the slide's abutment. Too far for proof equalzing. Time to cut the faces of lugs 1 and 2 by enough to
bring #3 into play, or at least close enough to equalize it by proof-firing...which is a maximum of .002 inch. This meant that the static headspace would be increased by .008 inch by the time all lugs were equalized, leaving .007 inch at most to finish, depending on how close I could get it
in the initial fit. A sheet of 20-bond typing paper is barely more than .004 in thickness, so I'd have to be deft with the reamer. The fact that it was spankin' new would make the job easier, but because it was so sharp, just a little too much pressure
would cut farther than Henry wanted me to. Initial static headspace was to be set at .895 inch...or .003 inch under minimum.
It took me 6 hours to get the lugs into contact. #2 was solid. The others were lightly kissing,
allowing just a little for final equalizing. Now to the hood. it had to be carefully cut...by hand...to allow the sides to enter the recess with just a bit of light contact. Final adjustment to be made after the length was set. Length was to be cut so that the barrel would enter the slide with medium thumb pressure. A square was used to check the lateral misalignment, and adjustment made on one side of the hood. Final clearance was just .002 inch per side with a light interference fit at the breechface. Static headspace checked with a special short GO gauge and a strip of paper suggested an approximate dimension of .890 inch. I wanted to go home, but I had to stay with it, if I had to stay until midnight.
On to the lower lug and the test fit into battery. There were no handy lug cutting tools...just a round file, a scrape made from a lathe bit...and my trembling hands. The round file was used in a draw-file motion, pulling it sideways on the lug to shorten and blend with the rear radius.
The scrape was used for fine adjustment after trial fitting. The gun finally went into battery with hard pressure on the back. The slide was just barely rearward of the frame. The disconnector reset as per design, but the thumb safety notch was a little shy of perfect alignment. Vertical lockup was tight, to say the least.
Out came a ground and hardened .196 rod and the lapping compound. The rod had a T-handle
brazed to one end. Another identical rod with a .198 diameter was also on the bench...in case we needed it...and the lapping began. I moved the slide forward and inserted the rod through the slidestop pin hole...and let it go under recoil spring pressure...and turned the rod to walk the slide forward. Reapplying the compound on every other pass, I got the slide to battery
about the time my hand felt like IT was locking up.
He handed me a slidestop. The slide refused to go smoothly, and we turned to the .198 rod for the final fit. It didn't go much faster than the initial fit because after every pass, I had to take the gun apart...rinse out all the compound...and try the slidestop. When the slide finally went to battery on the slidestop...just a wee bit tight...lapping compound was again applied to the
stop crosspin, and the slide hand-cycled about 5 times. Perfect!
Whoops! A problem with the barrel to slide clearance in full linkdown emerges...The clearance is good at .015 inch...but it occurs at .300 inch of slide travel instead of .250 inch. OMG!
Not a biggie, sez Uncle Henry. The barrel is stopping on the vertical impact surface like it should. The problem is at the front radius of the lower lug. It's not letting the barrel drop fast enough. Reshape it to reduce the sizeof the radius...elongate the top of the link hole just a bit,
(Seems like it required .002 inch) and you're probably good to go. Turned out that he was right. Imagine THAT!
Lug equalizing was done under pressure with handloaded rounds with cases measured to
insure that the gun would go to full battery. Three rounds later, we returned to the bench and
looked things over. The short GO gauge was inserted...but this time the strip of paper slipped out from between the gauge and the slide without tearing. Headspace was estimated at
.894 inch. The lugs had seated and increased the static headspace, and this about was as far as it would go. Time to decide. Was I building the gun for maximum accuracy...or was maximum reliability my goal? I opted for reliability. Henry was a little disappointed, but let me go with that. He said that I'd need to open up the hood clearance another thousandth or two per side. Okay then...Remember to cut a bevel on the underside of the hood. Yessir.
He attached a stop collar onto the reamer and reminded me of the "Rule of Halves." I placed the reamer into the chamber and pushed it into contact with the shoulder... and slid the collar
lightly against the chamber hood. The reamer had a little light interference in the forward (approximately) 32nd inch of the chamber, and he told me to turn it once slowly to remove the taper...then bring the reamer out and clean the chips off. The second pass still suggested there was still a little taper, and the process repeated. The third pass put the reamer into solid contact with the shoulder. I slipped the collar back into contact with the face of the hood...under its own weight only...and locked it down. With light forward pressure on the tap handle, I turned the reamer once...backed it out...cleaned the chamber, and checked the headspace with a standard .898 GO gauge. Almost! Cleaned the reamer again and
reset the stop collar. NOT...quite! A tick more. DAMMIT! Too much! Henry reckoned that my final static headspace was .900 inch. Firing the gun a few hundred rounds would probably open that up by maybe another thousandth as the lugs settled in and took a final, solid seat. The barrel was now not only precisely fitted to the gun...it would likely wear completely out before the headspace would increase to the point of causing a problem. The locked breech pistol was now as strong as the design would allow. The light "seating" flange was dressed off the lugs with a stone. (Lookin' good, just like Hollywood!)
The bushing fit was straightforward, done pretty much like any other match bushing with just the tiniest bit of interference as the barrel approached final lock without springing or producing any linkdown problems. That part I was able to do without coaching, and the gun was wicked accurate. I actually wound up fitting a second, looser bushing to the gun for reliability...but I don't think it was ever used. I'm still tryin' to buy the gun from my cousin...but he's a tough nut to crack. It'll still part your hair at 25 paces. I shot it about 3 years ago. Cuzzin refuses to sell, but will trade for my Union Switch...NOT!
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