I just bought the dies to start reloading .45 LC and was going to use some old Winchester large pistol primers I've had for probably 20 years. I loaded a few primers into resized once-fired Starline cases from HSM cowboy loads. I placed one primed case in my Uberti and set it off. It fired just fine but the cylinder wouldn't rotate. Finally got it worked around to the loading gate and the primer had obvious pressure signs. I have heard of pressure issues with old powder but never thought an old primer in an empty case could show pressure signs like that.

Could it be something with the cases?

Thanks.