I used to load a lot of 45-70. But I no longer have any rifles in that caliber. I do have many friends who do however and some of those rifles used to be mine.
So,,,,,,,,will the 325 FTX "preform"
Yes!

How do I know?

Well I have used 340 and 325 grain hard cast bullets on deer in years past and they didn't expand at all. In fact I have used bullets from 300 to 550 grains at speeds from sub-sonic up to 1900 fps depending on the exact load. They all worked fine, and some, were used to kill bear and elk too. A light load from a 45-70 is the full equal, (plus some,) of any 44 Mag handgun, and I have killed a lot of game with 44s from revolvers. In my life (so far) I have never had to shoot twice either.

If you look out your window I am sure you will NOT see about 167,000,000 buffalo.
One of the reasons you don't see them is the old 500 grain round nose soft lead bullets of the 1870s-1880s and they left the muzzle of 32 inch long barrels at only about 1200 FPS, but killed 1500 to 2300 pound buffalo easily, and at some pretty long distances too.

The 45-70 is still a fairly popular rifle for Wyoming hunters in the northern and western parts of the state because they kill elk very well, but also because they are very comforting when you are surrounded by grizzlies. We are!

The FTX has a reputation for being fairly "soft" and expanding very violently and for a lack of penetration as compared to many other bullets.............when used on elk, moose, big bears and buffalo.

But you are talking about deer!
Don't over-think this! You are very well armed with a 45-70. Trust it, and go out and practice until you cna hit running rabbits with it. If you shoot well you will NEVER have to worry that your 45-70 may be lacking.

I think about ANY bullet you can load in a 45-70, at ANY muzzle velocity of 900 FPS or faster is going to be just fine for ANY whitetail that ever walked in the N. American continent.

Go kill some and then come back here and tell us all how well it worked You will not likely recover the bullet, but we'd be interested in the shot angle and the size of the wound channel.

Last edited by szihn; 06/25/18.