A 140 gn .270 BTSP interlock.
One died after running a quarter mile with a nice double lung shot, the one that I took out the shoulder blade on dropped instantly but didn't die for another 10 minutes until we could walk up to it, see it still breathing and end its suffering, after that I switched to Nosler permanently and never had one go more than 10 yards.
My dad still uses hornady in a 308, also BTSP with interlock, and has lost 2 bucks that ran a half mile on to a unneighborly neighbors property, despite finding chunks of lung tissue at the site of impact. I just have a hard time believing there is any significant expansion or damage to internals with their ammo designed for quick expansion. I have only seen two kills I would consider clean with a Hornady, one was a CNS shot and one hit the aorta on a small doe and she bleed out quick.
Hello Lbarr,
And, welcome to the world's best forum.
Your fail-to-expand experiences are exactly the opposite of mine with Hornady "Interlock" projectiles.
I did shoot a caliber .270 Winchester / 150 grain spire point, broadside through a caribou's lungs and the exit wound showed only a very slight increase, compared to the approximately .27 caliber entrance wound.
Conversely, 130 gr spire points in that caliber generally did not exit caribou or blacktail deer, in my experiences with same.
Admittedly however, I've no experience with the latest boat tail version.
All the critters I've shot with Interlocks have been with either their original flat based round nose soft and / or their original flat base spire point, in various calibers.
I have found the pointy ones to be only a tad bit less soft than Sierra's equivalent bullets, in other words flat based spitzer soft points in the same calibers and weights, velocities, etc.
On the other hand, Hornady's good old "Interlock" round nose softs seem fairly tough at "non-magnum" / low to moderate striking velocities (my experiences in both Alaska and Africa as well).
Nonetheless, I've never seen one fail to expand on any hooved animal (they pass through rodents with, judging by the wounds, to be little or expansion-lol).
I guess your own and my own pretty much opposite experiences with Hornady Interlocks, is a perfect illustration of; "One man's bread is another man's poison".
Cheers,
Velo Dog.