Yes, but they present multiple challenges. First, they are launched using black powder to keep pressures low enough to fire in the cheap, plastic flare pistols. Your shotgun will require cleaning like a muzzleloader. Second, if they are fired anywhere but over water, they will ignite any combustible material such as dry grass. The 12 gauge flares almost always burn all the way down. Don't ask me how I know. I much prefer the 26.5 mm surplus flare pistols and ammo. They can be ordered online from Dan's Sporting Goods and marine supply outlets.
