According to this report a box of .45 ammo on the U.K. black market cost from £2,000 to £3,000 ($4000 to $6000). Talk about opportunities for a profit! That has to to be more lucrative than drugs.
At second thought I think there must have been a mistake made somewhere along the way. They also say a .38 “bullet” cost £0.50 which would translate into about $50 for a box of fifty. Why would .45 ammo cost 100 times that of .38 ammo? Still there is more than adequate markup for someone with a Dillon 1050 to make a lot of money in their basement.