Ok, I can see that a light hit might cause strange primer ignition, I guess, which could cause the powder to burn weird, if you failed to follow through on the trigger pull. Maybe. But as I mentioned earlier, the H&R transfer bar won't even come up if you don't follow through. If you stop the trigger pull as soon as the shot breaks, the bar won't even come up. You've got to follow through to bring it up at all. Maybe if you stop the follow through just after the shot breaks, when the transfer bar is partially up, it could cause such a strange situation.
But I don't see it as a problem with the rifle. I still see it as a problem with the shooter's trigger technique. I've never seen this happen, though, and I've had H&R rifles for eight years.
Possibly the pin holding the transfer bar is broken, and only allowing the bar to come up partially. But in that case, the 'fix' is to replace the pin. I guess if this were happening to me, and I were SURE that it wasn't my technique, I'd take the assembly apart and verify it was operating properly. But I wouldn't blame it on a "known problem" of the rifle.