Been a while, old fart can't remember, need help

[DaveInFloweryBranchGA]

With most barrels, when you're wanting to get the groove diameter, one simply pushes a lead slug through and measures the diameter. This becomes a bit more difficult when the number of lands is odd instead of even, such as in a Lee Enfield 5 groove.

At one time, I'd read and used a method of using getting/measuring the groove diameter on odd number of lands, but didn't write it down and for the life of me, I can't remember how it was done.

At the present, I've got a Pietta revolver that I'm told has an odd number of lands, so I'm wanting to measure it. Would somebody help the old fart out and remind him of how to measure odd number barrels? I could probably figure it out, but I'm hip deep in alligators trying to start a new business and can't see the swamp. I'm so darn busy I don't even have time to shoot or reload.:(

But I do want to get this revolver ready to shoot when I've got more time in a month.

[Master_Mechanic]

Slug it traditionally, wrap a known size feeler guage around he slug mic it and subtract twice. The thickness of the feeler guage.

[RedHawk357Mag]

http://castboolits.gunloads.com/showthread.php?t=119952
This was a help if I remember correctly

[Char-Gar]

I was measuring such odd number groove slugs long before folks started saying it can't be done with an ordinary micrometer. I slowly rotate the slug as I open the mic jaws. You will feel a slight tic as it rotates at it's largest diameter. It will be on the outside edge of two grooves. The measurement will be as accurate as those taken with special equipment and lots of fuss.

[Bzcraig]

I was measuring such odd number groove slugs long before folks started saying it can't be done with an ordinary micrometer. I slowly rotate the slug as I open the mic jaws. You will feel a slight tic as it rotates at it's largest diameter. It will be on the outside edge of two grooves. The measurement will be as accurate as those taken with special equipment and lots of fuss.

I don't know how accurate it is but I use the same method and haven't had any problems with leading so I guess it's good enough for the girls I go with.

[DaveInFloweryBranchGA]

I remember something along the lines you fellas are suggesting and I'm sure they're going to be accurate enough for my purposes, which is to match boolit size reasonably well to groove diameter. Lead, especially soft pure lead, is a forgiving material when working with it as a boolit, assuming you have with a certain degree of caution and stay within boundaries.

I'll get myself a fishing sinker out, slug the bore and see how things go.

[edctexas]

Careful about those fishing sinkers!! Most of what is sold today are not soft lead! How do I know?? Look at Cabelas online. I went to a local place that has both shooting and fishing gear. They had no lead sinkers. Their gunsmith gave a piece of lead wire to use. The new sinkers are California compliant!

Ed C

[DaveInFloweryBranchGA]

Ed, that's certainly true of fishing tackle bought today. Luckily for me, mine were bought a good long time ago and I don't use very many. Gotta love that backdoor gun control effort, eh?

[Char-Gar]

A moment of truth telling: There really is no serious need to slug the bore of standard factory made firearms either rifle or handgun. The cast bullet sizing is determined by the size of the throat (chamber or cylinder) in the firearms. Barrels sizes are pretty much irrelevant and are 99.9 percent within a fairly narrow range anyway.

The old mantra "slug the bore" is pretty much hog wash. That is not the first thing you do, it is the last when you are having problems and throat sizing is not cutting it, which is pretty much never.

[BruceB]

Dang.... Chargar and BruceB are on the same wavelength AGAIN!

I simply don't remember the last time i slugged a bore. It was certainly many years ago.

My normal routine calls for loading bullets which are sized "on the high side" of whatever diameter is nominal for the cartridge involved. For example, ALL my .30-caliber rifles shoot bullets sized at .311", with the "fat thirties" and older-production rifles get something larger.... these would be the .303 British and .30-40 Krags, for example.

The ammunition works great, and the complexities are much-reduced.

K-I-S-S, y'all.

[DaveInFloweryBranchGA]

Char-Gar & BruceB,

The issue with the Pietta isn't a problem revolver persay, it's an undersized cylinder related to the barrel on these Italian made revolvers. I want to be able to shoot a boolit/ball that's not going to be sized down more than I want by the cylinder when the revolver is loaded.

So this is why I'm wanting a groove diameter. I want to get the revolver chambers to a closer match of the barrel. Sounds like another methodology might be preferably, perhaps one with some (another brain fart) that casting material?