PintsofCraft,
As I have pointed out a couple of times on this thread, impact velocity has a lot to do with cup-and-core effectiveness (and hence "toughness). Have not used the .35 220 Speer flat-nose on game that I can recall, but have seen the .35 i8o at work--but at a modest muzzle velocity of around 1850 fps, from my wife's old German combination gun, with a 16-gauge shotgun barrel and a rifle barrel chambered for the 9x72R, a round that originated in black powder days.This gun is nitro-proved, and turned out to have a bore/groove diameter typical of American .35-caliber cartridges. The 180 Speer has knocked the snot out of deer out to around 150 yards (which is about as far as the trajectory holds up), and we have never recovered one.
I'm wondering when you started using the Hornadys? I ask because even before the Interlock ring they worked better than most cup-and-cores. I've only been using the .30-06 for 45 years (Colorado Bob has five years on me), but among the first bullets I used in it were both the 180-grain Spire Point and Round-Nose, which both worked very well at the typical 2700 fps--so well I started using 150 Spire Points in my first .270, at around 2900 fps. They also worked very well, expanding and penetrating great. I found out many years later this was because Hornady used a slightly harder lead-alloy in them--even before they added the Interlock ring.
