I had an AWA Lightning in 45 colt. It was worked over by Eldon Penner. It fed like oiled ice. Never missed one as long as it was not run too fast. With the ramp feed, if you shoot too fast, the cartridge hops off the carrier and noses into the top of the chamber on the way in. He felt that the 44-40 was better and the 38-40 was the best cartridge in them because they fed better. It would make sense that the smaller the bullet, there would be less tendency for a bullet hopping up and snagging on the top of the chamber edge on the way in.
Eldon also mentioned that the bottleneck seemed to have less blow-back because of the nature of the 44-40 and 38-40 case being thinner and sealing the chamber better.