I haven't heard of a 45-70 that it doesn't feed smoothly in. However no one has asked about Winchesters or Brownings either. Lets find out. I can send you a coupld samples if you want use the M profile, or--
If I were using a 45-70 I would use the LFN without a crimp groove. It will feed very smoothly in any lever gun when seated to the proper depth for the gun. Crimping with a Lee factory crimp finishes the ammo so the bullets can't be driven back into the case from recoil. The LFN had a larger meplat so it kills well with a bit less velocity than the M bullet.
The M bullet is at it's best when driven to the guns limit, for milking the maximum range, flatest trajectory possible from a 45-70, with good killing power, but not optimum killing power. Since most 45-70 lever shooters are most interested in woods ranges, say out to 200 yards, AND DON'T WANT HEAVIER RECOIL THAN NECESSARY, the LFN is actually the best suited. It definately isn't limited to 200 yards, but it's trajectory is a bit more curved than the M.
