On any rifle it should be front trigger first, without regard to bore size. The hand movements become so automatic it would be disasterous to use one method with large bores and another method with small bores.

In an analogous situation, this is the reason I cannot own a rifle or shotgun with a single trigger. Every time I try to shoot a single trigger gun, on a follow-up shot I find myself pulling the rear of the trigger guard and wondering why the gun won't go off.

If the shooter is doubling a large rifle because his finger is slipping off the front trigger he needs to improve his technique. That shooter certainly isn't up to the task of hunting dangerous game, and switching to rear trigger first is not an improvement of his shooting ability.

Curl