Modifying an Investarm barrel?er building forum so please

[Canuck Bob]

I have an Euroarms of America Mountain style rifle I bought cheap, no pitting and in sound condition. Typical Investarms half stock .45 with a 28" barrel percussion rifle bought cheap. I also have a 9" South Bend lathe that turns 36" between centers.

My questions revolve around using this collection of parts to make a LH flintlock rifle homespun kit. The headstock draft of the lathe is 29/32 and the barrel is a 15/16" .45. Rifle sellers make 13/16" barrels for .45 as what looks like a standard small sized barrel. I found no 3/4" .45 barrels in a quick survey.

Is 3/4" round Investarm steel barrel a safe size for a .45 flintlock rifle? Or maybe a 13/16" breech straight for a few inches then tapering to 29/32 then a long taper to 3/4" at the muzzle. I will be shooting 50 paces range loads mainly but want it safe for hunting loads if I move it on.

I'm also considering a NW Trade gun octagon to round profile with 7/8" octagon tapering to the wedding bands. I'll have to work the current 15/16" breech with a file and have no idea if this is even possible for 6-8" of barrel.

I have very little into this rifle and am more than willing to use it as a disposable flintlock rifle building education for a much more correct build later.

I've posted on the other building forum as well.

 

[eggwelder]

Canuck Bob, you may get better or some answers anyway over on another forum. am sending you a PM

 

[Zonie]

According to my calculations, the reason you aren't finding any 3 /4" barrels in .45 caliber is because of the resulting wall thickness.
When rifling depths are added to the .45 caliber bore it leaves only about .143" of wall.

IMO, you can leave maybe 8-10" of the octagon and then start tapering the barrel down to the smaller size without having any problems with safety.