My browser is acting funny' I hope this doesn't go in multiple times. If so, I hope the moderator will douse all of 'em but one :-)
Since abt. 1962, looking at R. Southgate's work in Franklin TN, just below my Nashville home, I've been interested in making a barrel myself. Well, I've gotten into a project for which the home reboring fits quite well.
Has anyone on the forum done this using a home0made machine? Want to advise?
I've conceived a very compact and rigid machine thart I can easily build under my shade tree. It is convertible for both boring and rifling, though I may use my engine lathe for the goring.reaming chores.
This project is a short, full0stocked woods rifle, Mannlicher0style, on a Swedish Mauser. I've had the rifle sporterized for quite some time and it shoots well in 6.5mm. This conversion will just be barrel work. I plan to shoot a .40 cal, 300-330 gr paper jackreted cast bullet at around 16-1700 fps.. IOW, I want a good solid 200 yd deer/bear/boar rifle to these E. TN mountains.
Some of the information I lack may need to come from the black powder forums, but I';; put all the queries here and ask folks on those forums to congregate here if the are willing to help.
Taking the gunsmithing questions first, I have been unable to find what a rifling cutter looks like. I can imagine the cutting form easily, but I wonder if it uses a single hook or multiple hooks on one cutter/ If multiple, to the successive teeth get taller and if so, by how much? I've designed the cutter carrier rod with a milled slot, cut at the spiral angle, in which the paper strips can be placed to raise the cutter for successive passes.
What can I expect as far as amount of cut per pass? How many passes for each sheet of paper? Should this paper be really thin, or will something like .003" thickness work? Are all grooves (6) cut progressively, or cut one fully then go on to the next (I suspect the former)?
BTW, if anyone knows of websites that show this, I'd appreciated links... I have looked, and resscearched in books, but I'm severely visually handicapped, so research is slow and spotty for me.
Now, as for sizing the bore, I can make this any caliber whatsoever, and for reasons having to do with neck thickness of brass, I haven't entirely settled on it yet, but let's talk about a .416" groove-to-groove diameter, just to put some dimensions down. What I've read indicates that rather deeper grooves are better for paper jacketed bullets, but I've not found a fixed number for that. I've read that the bullet should cast or be sized to exactly the fore diameter. So, if the grooves are .005" deep, then the bullet will be made .406". Are these good figures? I've never shot PJ bullets, so I'm in the dark except for some reading. If the grooves don't need to be that deep, i'd be pleased to know.
How about groove width? Lands & grooves identical width? Better if grooves wider? The most convenient would be to have grooves 1/8" and lands 3/32" wide... this makes the tooling a bit easier, but not importantly so..
Well, there's the first round of questions. I'll stop here and see if anyone is interested in this project. Your experienced comments/advice are welcomed, but I'd really rather not have "speculative insights" from well-wishing but inexperienced folks. I'd invite those to pull up a bit of ground around the campfire, grab a cup of coffee, and learn along with me :-)
Cheers/buffler
