I'm not very shotgun smart and I need some help. I have an old H&R Topper in .410. The stampings say it will take 3 inch shells. When I look in the chamber there is a little ledge in the bore about 3 inches in that is obviously positioned to accomodate a 3" shell. My question is will using shorter shells hurt anything? I'm guessing no, but I want to be sure. Thanks for any input.
Thanks guys. I know the ledge doesn't position the shell, rather I was concerned that with a 2.5 inch shell the ledge would be half an inch in front of the shell. I didn't know if the gap between the end of the shell and the ledge would cause a problem. I'm guessing it's too short of a distance for anything to expand enough to get caught on the ledge. Am I correct or am I missing something?
The stampings say 3"FULL and then there is a P with a circle around it. I figured out 3" chamber with a full choke barrel. Don't know about the circled P. You can look down the bore and see that there is a taper that runs from the chamber to the muzzle. You can also see where the chamber was machined in. The transition between the parallel walls of the chamber and the tapered bore is a step consisting of two 90 degree angles. The step is slightly thicker on one side where the machining was not perfect. If it was a quick taper I wouldn't be concerned, but this hard edged step makes me pause and ask some questions before I tear something up. I just looked at it again to be sure of the hard edge and that's what is in there. Am I still good? Thanks for the help.
I guess that the step at the chamber's end is cheaper to machine in than a short taper would be. But that doesn't change the advice you've been given. You can safely use 3" shells, and also anything of shorter length.
The P-in-a-circle is a proof mark, I believe. If I'm correct, it indicates that the barrelled action has withstood a certain level of overcharge, to prove that it's safe to use.
I, too, believe that the 3"FULL mark indicates a full choke and a 3" chamber.