1) Grenade launcher
Found on
https://www.crosswordclues.com/clue/manville-gun
The Manville gun was a stockless, semi-automatic, revolver type gun, introduced in 1935 by Charles J. Manville. The Manville Gun was a large weapon, with a heavy cylinder being rotated for each shot by a clockwork-type spring. The spring was wound manually during the reloading. By 1938 Manville had introduced three different bore diameter versions...
Found on
http://en.wikipedia.org/wiki/Manville_gun
No exact match found.
