On Starline's website, under the text for the 44-40 case, I found this:
*It has come to our attention that some Uberti revolvers have issues with light hammer strikes and will only fire with Federal primers, which we generally recommend for revolvers anyway."
In my own experience with various, mostly vintage, Colt and Smith & Wesson revolvers, I have had no problems with various primers from all the "usual suspects" - CCI, Winchester, Remington, as well as Federal.
Have you guys noticed that Federal (pistol) primers are easier to set off than other brands?
I didn't know this, and am not certain it's true, although Starline is a reputable outfit, I don't think they would put this on their website unless they had good reason. What say you?