The heaviest caliber for this match would be 300 Win Mag.
However, we will be hosting a 1 mile shoot this coming spring, more info on that later... then you can bring the big gun.
Since we have to spot our own shots for this Practical Long Range Riflery shoot, it's best to have a rifle that doesn't "get away from you" on recoil... many guys shoot silencers... most of us do not. Muzzle brakes okay... just 300WM max.
I actually shot a stock Savage 270 in the last match, with a 4 power scope. I don't score my own hits, since I'd basically have a "home field advantage," but I did want to demonstrate that hits could be made at long ranges with pretty unassuming equipment. The Savage 110 was totally unmodified (I didn't even lighten the Accutrigger from factory setting), and I used a cheap Bushnell 4 power scope to dial shots. I made first round hits at 825 and 1040... I fared less well at 600 yards for some reason... but a second round hit at 750 wasn't bad.
I said that only to emphasize that you can really do this with some pretty standard gear. I designed a little "rev and clock" system to mark zero ranges on the Bushnell 4x scope's coin slot turret... and oddly enough, it works.
So you don't necessarily need a high dollar rifle to get in on the fun--and perhaps even win. The winner of last Saturday's match was not shooting the most expensive rifle on the line--far from it, but his score was the important thing--and he took home the 100 dollar top prize.
We hope to have these shoots every month to 6 weeks, even through the winter... planning a "polar bear" shoot in January or February of this coming year. Should be fun.