Trapdoor slugged barrel

[Paulj]

I slugged the barrel on my 1882 model year trapdoor for the fun of it and see where it hardly has any lands or grooves. It measure about .454 and shoots well for my old eyes so I can't complain. Is this a normal looking slug or has the barrel been shot out?
thanks.
slugged barrel.jpg

[Dick Hosmer]

That's pretty clear rifling. I'd question your measurement, though. You need to be sure that the point of tangency between mic and slug is exactly on opposing high-points, else you will read small - which I think is what you are reporting. 0.454" (if true) is UNDER nominal, so it certainly is not "shot out". What diameter bullet are you using? Cast? Factory jacketed? Cowboy?

[Paulj]

I shoot .458 sized cast bullets only with black powder. I'll measure again tomorrow.
Thanks.

[Bob S]

You really need a 120 degree vee anvil micrometer to get an accurate measurement. If you want to send me a slug,
I'd be happy to measure it for you.

Resepectfully,
Bob S.

[Paulj]

Thanks for the offer Bob but I don't want to bother you. I'm happy with what I got and it shoots fine for my needs. What would be normal rifling for an 1882 built rifle? How many lands and grooves? Can someone post pics of there slugged rifles so i can compare? Along with shooting, reloading, casting, etc, since I was a teenager( 60 now) I enjoy all aspects of the guns I have and just want to learn more.
Thanks again.

[Dick Hosmer]

Nearly all .45-70 trapdoors are rifled with three broad lands/grooves of nearly identical width, 22 inch twist, RH. The fact that the L&G are basically equal allows the (careful) use of a standard mic to come awfully close, something NOT possible with other odd-numbered set-ups, as Bob rightly points out.

There are a few exceptions. A handful of guns have the same rifling, but LH twist. These were almost certainly used in determining the drift for the M1884 Buffington sight. I own such a carbine, which will be shown in my forthcoming book.

The Long Range rifles (mostly .45-80) of 1881 have a 19-5/8" RH twist, 6 grooves. In that case, the lands are much narrower then the grooves. Why they picked such an 'odd' twist rate is not known to me. They will also be in the book.

You have the standard service rifling as described in the first sentence. Hope that helps.

[p246]

My model 1884 made in 1889 slugged at .460. It would key hole purchased 405 grain stuff. Got a mold made to drop 500 grain FB using pure lead with tin added. Got a Lee custom .461 push through sizer. Shoots great with that bullet. I use a compression die, drill out the primer flash hole, magnum primer and 60 grains of black. Pokes nice holes in paper anyway.

[Dick Hosmer]

Properly loaded (and bullet size is the key) in a rifle with a fine bore, and with a good shooter, on a good day, the old trapdoor is capable of some surprising results, even occasionally flirting with 1 MOA out to ranges where iron sights, drop and wind take their toll.