I took the Maynard to the range, set up single clay birds hanging on a string and fired away with the .410 shells (reloads and some factory loads). From 25 yds, the clay birds disappeared under the withering .410 blasts. 21 shots, no misfires. The barrel and the sleeve adaptor never even got warm. I'll try with a bird thrower next week.
The sleeve adapter cost me about $20 a few years ago. It took some time fitting it with a file and drill press, but it works. 410s can be fun.