On the subject of which ammo is best for the 392......I have had very good success with JSB 18.13 gr and for that matter, Crosman domes. Not the hp. A noticeable diff. That said, I recently tore down my 392 completely, drilled/ported the valve exhaust, two spring mod, drilled the transfer port to match the valve outlet......and now can NOT hit hit a bullseye to save my life. As Tim says, I'm gaining experience LOL. The bore on the 392s is rumored to be on the large side and pushing a pellet through the barrel would support that. I have had best accuracy with the H&N in 5.54 head size and just ordered a 5.55mm batch to see what there is to see. I had to go an mess with it. It doesnt' shoot any faster but it does shoot much less accurately. I've found the HN 5.55 to be the best pellet in my 392. Still not nearly as accurate as most of my vintage guns.