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View Full Version : Tapered bore in the Uberti Hi-Wall



Buckshot
12-05-2007, 05:34 AM
.................Anone else notice this? I had upset a slug in the barrel just ahead of the chamber when I got the rifle. The result was .373" x .3794". This evening I was making a core forming die for a second shot at a swage die for paper patching for this rifle. The rifle was leaning against the bench and since I had the pin gages out I took a .373" (they're a minus .0002"set) and it wouldn't go.

Neither would a .372". It would just accept a .371" pin. While I had put a couple hundred rounds through it to date, I thought there still might be a wire edge turned up at the bore. Checking with 10x magnification it was good with no problem. Another quick and dirty test was to put the inside jaws of an electronic dial guesstimator in the muzzle.

It too showed a .371" bore. It couldn't decide between .379" and .3795" for the groove, but since it's resolution is a half thou I'm going to go with the .3794" the mike gave at the breech. At least until I get around to upsetting a slug at the muzzle. Inspecting the bore again from either end showed nothing I'd take as an abrupt change in the bore.

At least it's .371" at the muzzle and .373" at the breech and not vise versa :-)

...............Buckshot

DonH
12-05-2007, 06:41 AM
Harry Pope and other old-timers worked to achieve a taper in the bore to the muzzle. If it worked for them it works for me.

Boz330
12-05-2007, 09:35 AM
Pedersoli's are supposed to be the same way.

Bob

KCSO
12-05-2007, 10:46 AM
If you cut rifle a bore with older tooling it tapers automaticly as the cutter compresses slightly as ti travles from the breech end to the muzzle. That is why in the old days the breech end on a blank was always marked. I have found some modern rifles with tapered bores and have found a couple of rifles that wouldn't shoot well because the tapered barrel was installed backwards. According to Pope a bullet started at the muzzle should press in and then either dop to the breech or should slide there by blowing in the muzzle. The barrels I have recut with a slick all show at least 2 thou. taper.