Fox Collectors

Hi,
I have a Sterlingworth 12 gauge with what are not bulges but two very small "pimples" for lack of a better word on the underside of the left barrel. Not very noticeable. One is at 6 1/2 inches from the muzzle and the other at 16 inches just a couple inches in front of the for-end. Looking inside the best I could I don't see anything unusual.
Was wondering if someone could tell me what could have caused these and if they need to be looked at for a safety issue. I don't plan on shooting anything but RST in it.

Thanks much!

If the pimples are small, shot size, dents from the inside out you may be a victim of leaky reloads. If the less-than-tight crimp of the shell in the left barrel spits a couple of shot into the forceing cone on recoil from the right barrel discharging, pimples will appear as the second shot goes off and the wad and shot charge run over the loose shot. These little dents usually appear in the left barrel (second barrel fired) and on the bottom, where the loose shot settles. It happened to me. Steve Hutton knew what the cause was and explained it all. They are usually small enough to tap back in and should not be a safety issue.
Cheers,
DoubleGun

Thanks Doublegun. First time I've ever heard of this. It may just be the case.