Nick-
I seriously doubt that you're going to get anywhere with sabots and sub caliber bullets with this rifle.
So much to the point that I'd never bother with attempting that with the rifle myself whether it were mine or someone else's rifle.
Interior ballistics, pressure curves...
Stick to the right stuff here, Jeff Tanner will make you a custom roundball mould for under $50.00 USD and ship it to your door.
I'm interested to see photos of your chamber casts, really good photos -- contrasty enough to be able to clearly see the condition of the chamber walls on your castings.
As noted, a seven dram rifle will be much heavier that what you have there.
Three inch chambers on an H&H twelve bore rifle lead to that assumption, but considering the overall weight my sense right off the bat is that it's not a seven dram gun.
I'd like to see photos of those barrels, the barrel flats including all proof marks, and the action flats including all of the proof marks, as well as with a ruler laid on the barrel flats justified to the standing breeches.
I wonder if someone at some time has gone in there and lengthened the chambers to clean up a pitted throat.
Also I'm curious to see if it was set up for paper or thin brass cases.
On rifling twist, you'd be surprised at how many high quality brit bore rifles *set up from the factory for roundball* have 'too fast for roundball' rifling twist rate -- and shoot beautifully with roundball nonetheless.
What is the rifling profile?
How many lands?
What is the bore diameter?
Is the bore/groove the same at the muzzles as it is at the breech end?
Compare right and left barrels too, chances are that they're not exactly the same.
Are the barrels actually original equipment?
Photos please!
Can't wait to hear and the specifics on this rifle.
--Tinker
