serpantino: I should point out he's in the UK ;) things are rather different over here to the US.... also you can load an M203 with a buckshot round.
Wraith's location shows the US. And it doesn't matter where you're from, a shotgun is a shotgun and a grenade launcher is a launcher. There
are civilian sales of m203's, but under the NFA as it is, they're classified as "Destructive Devices" and their price reflects that (upwards of $2K + $200 FFL transfer tax). There are 25mm, 37mm, and 40mm flare launchers for sale on the civilian market that don't require a license to buy (but a hazmat license to sell and ship), but if you were to modify them in any way that allows for the firing of explosive shells, they automatically fall back under the Destructive Devices category, and now you've also got an illegally modified weapon, the punishment for which varies from state to state.
I know that teenage males (and some females) have a naturally unhealthy interest in explosives, but I will tell you from first (and second) hand (and foot, and various other body parts) experience that these are
not toys.
Back to the topic on hand. If you're going to handload, make sure you use top grade materials to minimize corrosion and other degradation. Cleaning after every session is great, but some chemicals "go to work" on the steel of your barrel as soon as it makes contact.
The best commercial rounds (IMHO) are Federal Premium or Fusion and Hornady, but they're not the cheapest. Winchester also sells what they call "Military Grade" ammo, replete with plain brown box and OD shells, but these are not, REPEAT:
NOT surplus military issue. Everyone who's tried them seems to love them, though.
If what you
really want is cheap plinking, invest in a .22 GSG-5. It looks cool (patterned after the HK MP5) and is a treat to shoot.