I have a H&R model 1915 single shot shotgun that my grandfather bought new back in the early to mid 1940's. He thought it was 28 ga. and bought two boxes of shells with it when he purchased the gun. After firing those two boxes, he could no longer find shotshells that would chamber in it. He and a friend then made a makeshift chamber sleeve to drop it to a .410. Unfortunately, when hacksawing the excess sleeve protruding from the chamber end of the barrel, he accedentally cut a little into the original barrel. He and my dad used the gun as a .410 for years, ejecting the spent shells with a screwdriver and pliers. When I received the gun, I removed the chamber sleeve and bought a box of 28 gauge shotshells only to find that they were .020"-.030" too large in dia. to fit in the chamber. The chamber end of the barrel is stamped "14mm gauge choke". Is this not a 28 gauge? If not, what is a 14mm gauge? By the way, the chamber length is 2 1/2". I have since trued the chamber end of the barrel were it was gouged by the hacksaw and made a better chamber sleeve and new ejector pin to extract the .410 shotshells. It shoots fine, but the pattern is loose as you might imagine due to the oversize barrel. I would love to find a replacement barrel either in the .410 or 28 ga. chambering. Anyone know where I might obtain one?

Thanks, Dave

After much surfing the web this past week, I now know what the 14mm shotgun is. What threw me off track for a while was the fact that the bore diameter of the 28 guage is .550" and a direct conversion of 14mm is .551". In reality the 14mm is a French designation for the 32 gauge even though no dimension of the 32 gauge equates to 14mm. Apparently the 32 gauge is still common in Europe and shells are still obtainable in the US. In fact I ordered a box of 32 gauge shells from Western Scrounger today. I am going to consult a gunsmith about repairing the damage to the chamber end of the barrel. I am still looking for a replacement barrel in chambered in either the .410 or the 28 gauge just because these shells are more readily available. If anyone knows where I might obtain one, please let me know.