Back in the early 80's I killed a few deer with 180gr. cast bullets at around 1800fps. Soft lead at that velocity, properly placed in the boiler room, made for some no-fooling-around kills. Certainly on a par with factory stuff.
Fast forward to 2005 'til I killed another one with a .30/30. Savage 99, W-W 170gr. Silvertip. Hit high in the shoulder, smashed spinal column. Bang-flop, needless to say.
Probably the most spectacular shot made with a .30/30 wasn't on a deer. 1992, swung on a running fox at around 75-100 yds in an open field. First shot hit about 2 feet behind him. Second shot at Br'er Fox was probably 50 yds. further on with him now in overdrive. Couldn't tell you how much I led him, but the shot took him through the right eyeball. Talk about luck.
