The "secret" to the success of the .30-30 is (and has always been) that it uses a relatively heavy bullet at a velosity that allows a fairly flat trajectory over 200 yards or so.
No matter how you try, the .30-30 will NEVER be a .308 or .30-06. It makes no sense to try to make it something it was never intended to be......such as using a lightweight bullet (130-150 grains) in an effort to flatten trajectory and thus losing the one thing it does well......penetrate!
The .30-30 made it's reputation with a 170 grain bullet and that bullet still works today. It's not spectacular, but it does the job it was intended to do with a heavy bullet at relatively mild velosity. Dropping down to a 150 grain bullet will not gain enough extra velosity to make the .30-30 into a flat-shooting killer......but it will reduce penetration to the point that it may (or may not) do it's job on heavy game.
The .303 Savage was basically identical to the .30-30 ballistically, but had a reputation for being a better killer on larger game (elk, moose, ect.) due to one thing......a heavier 190 grain bullet. It penetrated better and thus killed better. THAT is the "secret" to using a relatively mild round on heavy animals......bullet weight!
The Buffalo Bore loads with a 190 grain bullet in the .30-30 duplicate that performance. Will it kill better than a "standard" 170 grain load???? Probably not in most circumstances.....but it DOES give a bit of an edge if things aren't just right. It will duplicate those eary .303 Savage loads that earned a reputation over the typical .30-30.....for a REASON. They work!!!
