Barrel contour for a Greener Martini rifle

[rickw55]

I have a Greener Martini action that I hope one day to make in to a .45-70 rifle. I plan on using it for hunting and some non-competition target shooting.
I have a .45 barrel blank for it made by the Borchardt Rifle Company that I plan on using. I am confident that I can thread and install the barrel just fine. However, I can’t decide on what barrel contour to give to the barrel. I don’t want it to be too heavy, yet I don’t want it to be too light either.
What would you recommend? Which one of the standard contours would be suitable for this rifle? Or, would there be another contour that isn’t standard? I really like the look of a half-round, half-octagonal barrel, but I can’t do that with the equipment I have.
Thanks in advance for your replies.
Rick W

[elk hunter]

Rick,

Welcome to Cast Boolits.

You pose a difficult question as most of us do not know what standard contour you're asking about. For a 45 caliber hunting/light target rifle I favor a 30" barrel that is 1.30" at the breech and tapers to 1" or so at the muzzle. For target only I would go with 34" and straight 1.125". I too like half-round barrels and if you have access to a lathe making an octagon barrel into a half round one is quite easy. If you don't have access to a lathe then a machine shop or local gunsmith could do the work for a reasonable price.

Good luck with your project.

[rickw55]

Thanks for the reply.
The contours I was referring to are the ones listed on some barrel manufacturer's sites like Green Mountain:

• #2 Taper = 1.00" breech tapering to .85" muzzle
• #3 Taper = 1.05" breech tapering to .95" muzzle
• #3-1/2 Taper = 1.12" breech tapering to .95" muzzle
• #4 Taper = 1.12" breech tapering to 1.08" muzzle
• #5 Taper = 1.16" breech tapering to 1.12" muzzle
• #6 Taper = 1.30" breech tapering to 1.15" muzzle

My barrel blank is 30" long and 1.3 in diameter, so I could accommodate all of them. I wasn't sure what would be suitable for a .45-70.
I do have a lathe, but I'm at a loss on how to use it to make an octagon on the barrel, unless I file it. Can you elaborate on that, please?
Thanks for the welcome. I'm glad to be here!
Rick W

[elk hunter]

Rick,

You'll need a milling machine to make your round barrel octagon, then a lathe to turn the front of the barrel round. Someone with a NC or CNC mill can make your blank octagon for you. It can be done on a manual mill but, would probably be more expensive due to the time the operator has to stand there and run the machine.

Regards,

Elk Hunter