Can the smaller .410 shotshell be used in a .45/70 rifle? Is this true? What will happen if you do? Well, YouTuber The Emporium is taking on the experiment. Well, the shotshell fits in the chamber of this single shot .45/70 rifle. It will also fire, but with donut-shaped patterns due to the rifled barrel. Oh those case heads sure do bulge. In his last shot the firing pin actually pierced the primer. This shows us that you should not try this ever. Always only fire the cartridges or shells that are suggested by the manufacturer. See the 410 shotshell...