A C3 dealer can purchase post-86 machine guns for demonstration and sale to LE and authorized agencies.  To get a post-sample they need to get a letter from a police dept. or agency requesting a demonstration of each specific weapon. As long as they have their license, they can have the weapons; when they give up or lose their license the weapons can either be sold to another C3 dealer who can get a demo letter or they can be destroyed.  Getting the demo letter can be very difficult though if you're not properly connected.

A LEO can only possess and use a post-86 MG in the course of their employment. As far as getting post-86 MG's for their own personal use and possession, they're prohibited just like any other Joe Schmoe.

I have few questions about this as well

1) How can dealers rent post sample guns out for rent?  What part of that is demostrating for LE purchase?  Dont get me wrong, I like the ability to do that, just wondering.

2) How can dealers get demo letters for stuff like AK-47's and FA 10-22's that seem to have almost no use for LE in the US?  i.e. what PD in the US would consider buying a FA AK?

thanks

1.) You gotta get the letter.  Its as simple as that.  Once you've got the letter, you can get the guns.  Once you got the guns, you can rent them out - they're yours for as long as you have the license.

2.) Thats the hard part, and thats what I mean by being properly connected.  Guys I know have gotten letters for all sorts of nifty things; MG42's, AK47's, MAG58's, etc.  Not much "law enforcement use" for any of that stuff so have fun trying to convince the chief of police he needs to consider an MG42 for his dept.  Of course, if the chief of police is a fellow gun-nut or your buddy...

1: easy nothing prevents them from doing so once they get the letter they can do whatever they want with the gun.

2: get real cushy with a department head and they will probly sign for anything