I picked up a couple of the Greener Martini police actions at a recent gun show. I am going to build a 12 bore rifle on one of them but am looking for some thoughts from you gentleman before I order a barrel.

E.R Shaw offers a 24 inch 1 in 28" round barrel but I am more inclined to go with a longer twist, say 1 in 88" and octagon. The Gun Works has said they could do a 4140 barrel for me and they'll cut about any length and twist I want. I'm thinking the octagon barrel will weigh enough more than the round barrel to mitigate the recoil to a degree and I would like a bit longer barrel.

I intend to shoot primarily round ball in this rifle with brass cased shells. I may also use a conical from time to time. I know Accurate Molds has a couple of good looking 12 bore conicals.

I'd welcome any thoughts on this build as to barrel length, twist rates, bore and groove diameters, anything you thing might be helpful.

Thanks in advance guys.

Marty

Sorry
My modified large martini is in 444 Marlin



Originally was a 577-450 SHOT

Below are my regular 577-450 and the 577 Snider



Mike

That's a skookum barrel on that 444. I've ordered a 12 bore tapered octagon rifled barrel for one of my actions. Now I need to find someone to fit the barrel, hopefully here in Alaska.

Thanks, it is non-tapered and full diameter, it is for bench sitting and recoil taming.

I have a 12GA takedown Greener GP gun for which I had a second rifled barrel made. It was made from an ER Shaw blank. I just completed a fore end and have begun to shoot the only slugs I currently have for a rifled bore. They are Hornady 300 grain slugs in a sabot. The are very accurate but shoot high. I'll have to try something else. The gun is very accurate, however. I'll post a photo in a day or so.

You could try one of these. It an 12 bore, 1100 grain monster. The mold belongs to a friend of mine. He uses it in his Martini. His has a 1/36" barrel and he says it drives tacks. That's a 45 caliber 300 grain bullet for comparison.

Marty, I had good luck with conicals from NEI Mold #399, their .732 cotton spool weighing 835 grains, but this was in a Kodiak percussion double in .12 bore. They might need sizing down to fit your brass and chamber.
Love to see your gun when completed.