Oops, Sorry Bill it was 500Nitro that transitioned to the Martini Action.

Well, darn, my mistake.

Here's my plan. Numrich has an 1 1/8 58 cal. 27 inch octagon muzzleloading barrel.

Since the GP is a take down action l thought I would build an inline muzzle loading barrel for the GP. Interchangeable 12 guage shotgun. 58 cal muzzle loader. Not a muzzleloading Paradox gun I know. But a something to take up my spare time when I retire.