Just a heads up though, we did a movie last year using replica weapons (M4, M16) and there were some police issues to deal with, because government rules are an epic win, even if the replica isnt capable of firing anything.
There is no penalty for being in possession of a "replica firearm." There is a penalty for manufacturing or transferring or advertising or offering to sell a "replica firearm."
However, in our case, it was also including possession.
The fine isn't pleasent, I believe they also take the devices aswell.
So, just a handy dandy reminder, and if you're seen on the street with them, with a friend or something, or for some reason the local authorities invade your house, you still get in quite the large trouble. =P
Just be careful what you do with them if you make replica firearms, because they are illegal.