Yeah it was around 1/2" give or take, that's kinda what it shoots on average. I have not done much load developement with it though. At the F-class shoot I think I was shooting .3105 174 gr Hornady FMJ, and I can't recall the powder but I was using Norma brass, 210M primers, and it was running somewhere in that 2600-2700 fps range. Nothing like lobbing lead.
If your gun is shooting 1/2" on average you did get lucky with that barrel. I've shot a ton of these things and most times you are lucky if you get 1" at 100 after all the tuning without replacing the barrel. They were never meant to be tack drivers but to hit a man at 1-200 or so yards.
Forgot to mention, my rifle weights about 16 lbs.