The 0.5 calibre Desert Eagle gun is literally twice the size and your right, I see no practical use for it, I fired one shot and had no interest in firing another. It came as a package, probably about 10 Euros for a single shot.
Another participant fired the most powerful sniper rifle they had which cost 28 Euros for a single shot, Barret M99. I’m not kidding but 10 meters back with full ear defenders it was loud and and any bare skin you had, arms and face felt the shock wave.

https://en.m.wikipedia.org/wiki/Barrett_M99