this seems to be a fairly simple caliber to reload for, relatively speaking. make sure youre saving your brass, and maybe ask him to show you the ropes.
if you're doing any ammount of high volume shooting, you can really cut your cost per round quite a bit.
there's hardly any trimming to do, the brass being non-military isnt crimped primer pockets (so no swaging or reaming necessary), basically its clean, deprime, resize, refill.
with blem bullets (225 ftx) i've got a plinking load that costs me about $0.38/round.
and on stuff like the barnes or maker loads where you're gonna be paying $2 or more per round, you should be able to save around 70 cents or more per round by loading them yourself. A single stage press can pay for itself REAL fast with those kind of numbers.
http://a.co/0fEW4pU <--- lee reloading kit, $117 right now on sale
https://www.midwayusa.com/product/78730 ... -4-die-set <--- lee 450 bushmaster dies, $35
everything you need to get started except for a tumbler (and you could actually hand clean your brass if needed, with just a green scotch bright pad), and the actual reloading components themselves. If your buddy were to let you use his tumbler to get going, you could have the equipment for making your own 450 ammo for about $150.
1 pound of lil gun is gonna be around $25 (makes ~180-185 rounds) , primers are about $4-$5/100 (or $31-$35/1k ), and bullets themselves will depend on your projectile choice.
just some food for thought.