I have a FMJ model D derringer made by FMJ Company in Ducktown TN. I never had the guts to fire the thing It's a single shot breakdown design with a 3 3/8ths in barrel. It's chambered in .45 cal. LC and .410 shotshells in 2.5 in length only. I'd love to hear from someone who shot one or would like to shoot this one at Popguns some day I am there. Any takers?