oscarflytyer: I got the 3 groove. Haven't slugged the barrel yet to get measurements. Funny, this all started for me with a mold I re-hab'd for a friend's .375 H&H. I liked the look of the boolit and had it laying around when another friend got to see it. We laughed and talked about the boolit and, the long story short, I got my '94 converted, he went out and found a used Marlin 336 which is about to be converted, and another friend just quizzed me about the whole process so he can go out and have one of his '94's converted. It all started with a mold re-hab project.