Brother Dano, I have a few things to say, and they are all good. First, and foremost, I am SOOOOOO glad to see that you took your #1 shooting partner, and our next generation of shooters!!! We need to keep making them, because most kids shoot from a computer. Our industry, and heritage is dying to a computer. As far as your speed, I don't think that you are far off of your mark. Remember, with a high BC, you don't need THAT much speed. I wouldn't want to get hit with it! As far as the pressure goes, as the bullet is seated further out of the case, powder room increases, but, you are closer to the riflings. So it is sort of a slippery slope we walk at times. Effectively, if you were to fill that void with powder, the pressure would spike pre-maturely, due to bullet engagement, without a way to equally release the pressure. Result? flat primers, shiny spots, you get the drift. I think you are at a happy spot. Good accuracy, predictable, and SHOOTABLE!!!!! That last one is a biggy!
And I'll bet the dust really does kick up when you shoot prone. Mine kicks up dust without a brake, and will catch the grass on fire if I ain't careful. I have been having very good luck with RL25 in this Winchester. I have 3 loads and three bullet weights that it shoot very well, and it SEEMS to NOT be as temp sensitive as 22 so far.
Good luck to you and your son, and thats a great way to build memories that last!