Sorry this is so late coming-
: Yes- I have shot game, a single moose at 320yds with a .45-70, cast 550gr. bullet at1,670fps from an Italian actioned, custom barreled rifle. My sights were express sights, and the shot/hit were easy. The moose, a large dry cow, staggered 20 yds before dropping.
: I know there are very few hunters out there today, who've the accuracy and experience needed to shoot big game at 300yds with a scoped modern rifle, let alone a large bore with heavy bullets and it's attendent trajectory. There are many hunters out there who cannot hit a deer or moose at 100yd offhand, yet is the round they use only a 50 yds ctg. because of that fact?
: Many people think today as in one aiming point, holding over, etc. I don't. Even with my scoped rifles, I use Mil Dots, or plex posts for range estimations (or a lazer range finder) and know the impacts they give at various ranges. I've been in this game a while & as old Elmer said, "Hitting at long range is accidental, but if you practise at long range, you'll have more long range accidents than the guy who doesn't".
: Just because I said the rifle was a 300yds round, doens't mean everyone is able to shoot game at that range. I know I am, so for me, it's a 300yd round. I've a number of friends who also are capable of this type of shooting. We practise. For many people, it's a 100yd round. I know one like that as well, but then, for him, his .300 Wheatherby only a 100 yd round.
: Perhaps this is what I should have posted above.
: Properly loaded, the round has the power, but there is no substitute for practise.