Ive used speer BTSP for over 30 yrs , shot deer, elk , moose, mountain goats , bighorns, black bear, grizzly, antelope coyote out of 30-06 22-250 7mm-08 280 and 264 I like them.
There is not a 264 BTSP on their website.
Ya they were speer product but not sure which, sold it in the mid 80s the 22-250 were 70gr semi-spritzer as well.
