Leading

Like the .30-30 the .32spec/.32WCF cannot push a cast bullet beyond its max. Well, you can if you're casting pure lead and shooting a really light bullet, but even with something that soft if you are .002-.003 over groove and you have a decent lube. Most anything with a rim does well with cast and likely was designed for them originally.

No reason if the barrel's in good shape why it might not do better than 2"@100 if it likes the bullet and I bet it will pieplate at 200 if you figure the drop at range. Well worn m94's will often still shoot MOA with the right load if their bores didn't get eaten by corrosive primers and/or poor barrel hygiene.

You're using a Lee 8mm 175RNGC, right?
Alloy/size/lube/groove diam./please?

I will be loading that bullet for a friend this season in his m94 .32spec. I doubt this 40yr+ old rifle has had two boxes shot through it. Looks like it just came out of a time warp straight from the factory, not a scratch on it anywhere. 100% condition, Marbles post flip-up peep, kid got presented g'grandpa's rifle after using (successfully) a single shot shotgun the last three seasons. (If you knew how few deer there are around here you would be VERY impressed by that.) I'd leave it in the safe and hunt with a beater it's so pretty. Must have been g'g's spare rifle because no one has ever hunted with it. Somehow I can't see him letting me slug it unless I give him a Depends then drug and hog tie him, so it will be trial by error on the size and he can use the practice.

Let me know what powder you started with. I will likely start with 3031 and probably won't have to go any farther, but I have a dozen I can try. I actually have some .32 brass, won't have to form many and he should have some, too.