Winchester makes a cup and core round, sort of a half jacket, but the velocity isn't much higher. With all the black powder .38-40s out there, nobody makes a .38-40 for rifles any more.
100 years ago, there was a Winchester HV load offered for rifles only, but not now. Someone would shoot it in a '73 Colt or Winchester and sue.
Alliant lists some .38-40 loads using RE7 that raise the velocity quite a bit, without exceeding the old BP pressures. As I recall, one involves the Sierra 180 gr. HP .40 pistol bullet with MV of 1750 fps or so. I haven't tried it yet, but it sounds interesting.
