Pilots who like frangible rounds but can't get any of the government issue
can easily make their own by loading .45 cal shot shells with bits of wire
and small birdshot.
The Israelis, who have been using armed guards for years on their
aircraft, use a low velocity tumbling bullet that will stop a person but
supposedly will not decompress the aircraft if it misses and hits the
cabin wall.
I don't understand how filling a 45 cal shot shell with birdshot and
wire would achieve the same result.
Or is the US following a different path?
--
Tony Roberts
PP-ASEL
VFR OTT
Night
Almost Instrument 
Cessna 172H C-GICE