Since you asked...
The 781 practice are reloadable, the 576 buckshot are reloadable, I also have a patent on flashbang/stingball 40mm rounds that I reload, as well as comercially sold wood baton, rubber baton, smokes and flares. I use resin molded plastic, and make my own 576 carriers, that can be loaded with flechettes or #4 buckshot. I'm working on a sabot type carrier for flechettes at the present time, and have designed a few rounds for ALS Technologies. The casings made by CTS, ALS, MK Ballistic systems, and Def Tec can be easily reloaded, as well as the M-212 casings. As far as the HE type rounds, the casings can't be reloaded, but you can register a 407, and make it into a 406 HE, as long as you can produce RDX. Destiny Densley (Small Arms Review author on 40mm articles) has done just that. I prefer to reload the resin molded rounds, where I can produce rounds that look like and function like the real military pyrotechnic rounds.
It's a hobby...
Oh, and it's 2.4 -3 meters for the 381 and 382, 13.71 meters for the 433, to 14 meters for the 406 and 397 OCTOL.