I've been researching and doing some homework on bullets and loads for a 300 gr. bullet for the 45-70. What are some of your 300 gr. bullet choices and loads in the 45-70 for deer? Or do you think a 325 gr. or 350 gr. would be better. Any info would be appreciated. Thanks!

300 grain Barnes TSX
But, I actually use the 250 grain version. They work awesome. 2600 fps or so

I use the 405 grain Remington. But I did get some Federal 300's to try out.

The one I like the best is the Speer Unicor/Plinker. It has kept its integrity at muzzle velocities to just over 2200 fps, and I haven't tried it at any higher speeds. Accuracy is on par with the other brands I've tried.

Hornady and Sierra were well-behaved at MVs below 1900 fps, but animals showed signs of frangibility above that.

Not a hand load but I used to get great results with the 300gr JHP Remington factory load. Years ago I picked up a bunch of them on clearance. I was just starting to hand load for the 45-70 and needed the brass anyway.

They were very accurate and devastating on deer. I do not know if Remington still offers them. Other than some cast bullet loads I load 400gr bullets for hunting.

Speer 300gr Unicore with IMR4198 @ 48.5grs has been excellent from my 1895G. My velocity is 1987fps with great performance on whitetails.

The Horn 325 FTX bullet KILLs deer Well - RJ

My Henry shoots Barnes 300gr. TSX fn’s good. Only shot one deer with them, it died.

Over time, I found I prefer to use heavy bullets at a lower speed in the .45-70. I generally use 405 or heavier.

If you want to use 250 or 300 gr, you will most likely find you need to push them around 2000 fps or faster. I like 4198 for this

Every barrel is a bit different. As I recall, for my guide gun, 50gr was the sweet spot for both 300gr around 2000fps and 250gr jacketed bullets somewhere around 2250fps