What is the common method of tapering barrel bands and banded front sights to precisely fit a specific barrel? Do you need to turn a bar to the same taper as the barrel and lap? Buy a tapered cutter for every conceivable application? Thanks--

Wrap some 150 grit paper around the barrel, slide the band on, and lap away.

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Originally posted by billhilly66:
Wrap some 150 grit paper around the barrel, slide the band on, and lap away.

WHAT?????????

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Originally posted by Rick 0311:

quote:

Originally posted by billhilly66:
Wrap some 150 grit paper around the barrel, slide the band on, and lap away.

WHAT?????????

the sandpaper wrapped around the barrel will transfer the profile of the barrel (under the sandpaper) to the swivel by lapping away material.

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Originally posted by new_guy:

quote:

Originally posted by Rick 0311:

quote:

Originally posted by billhilly66:
Wrap some 150 grit paper around the barrel, slide the band on, and lap away.

WHAT?????????

the sandpaper wrapped around the barrel will transfer the profile of the barrel (under the sandpaper) to the swivel by lapping away material.

Whatever you say boss!

I use a boring bar in the lathe for both. Barrel bands are easy & usually tapered only about 0.010" over their short length. Banded ramps take more effort. I generally bore the band to match the barrel taper, then use files & grinding stomes in a Foredom tool on the ramp. Go slow & use Dykem to fit the ramp for a no-gap fit.
Roger

I've always heard that the old fashion way was to use a ball peen hammer with a freshly smoothed face to expand the metal of the band for teh perfect fit. Some of the old mster gunsmithing books I'm sure talk of this process...try The Modern Gunsmith by James V Howe...a great book!
Jeff P

The deep dark secert of tapering the ID of band ramps.

Measure the taper of the barrel per inch.
I normally figure it out for 3 inches so I can mark 3 inches out on the side of my compound slide on the lathe.
Divide by one half, as you are only cutting one side.

So now you have a taper in three inches, for example of .020" divided by half = .010" in three inches.
Now I dial in the compound of my lathe to .009" to .008" in three inches.

Yes you want the taper slightly smaller that the barel. Because the tail of the band ramp will flex as it being bored out. Also the tail will flex upward as you drive it on the barrel.This is IMPORTANT other wise you will have a GAP under the tail of the ramp once it is one the barrel. The RPM of the lathe will have to be slow, I set my lathe at 240 RPM, and try to take a max .005" depth of cut per pass so as to reduce the chatter in the tail because of the interupted cut. You can rough it out and then sharpen the cutter and do a couple of final passes.

When boring out a swivel band the dial in the taper dead on, because the length is so short as most are .600" to .750" in length.

Now with the tail of the ramp inside the three jaw chuck (this way you will not smack the tail of the ramp with the tool holder) bore the ID of the hole to with in .001" smaller that the diameter you need. Using the compound slide to bore out the taper.

Then you can polish the ID of the band with an split rod and emery cloth for the last little bit.

You want to be able to slide the ramp on to with in .100" of where you want it. You will be surprized how far you can drive the ramp on with a plastic mallet.

For the last 15 years I have used locktite to afix ramps and swivels, the old number used to be 609, it is used for bearing and bushings.

Jim Wisner
Custom Metalsmith

I had Jack Belk do one for me some years ago and he grabbed a round file and in about 30 minutes had a perfect fit, soldered it and I was on my way home...I can now do that myself after I did a couple of them, use a little smoke or Dicon if you must....

I suspect Jim Wisners approach is the better way, but the fact is if you can use a file, it will work...

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but the fact is if you can use a file, it will work...

Sadly, most cannot. For them, I think Mr. Wisner's approach will yield better looking results.

Great information, just what I was looking for. Thanks to all.