[Desert01]

Some of the 590's have the Steel trigger group some do not. The 500's have the plasitic trigger groups and are on most of the currently procured shotguns. The clean out tube barrel attachment is the biggest differance between the two models, although the current Mossberg 500 Breaching shotguns use the 5+1 590's clean out tube. You could convert a 500, but the 5+1 barrels are sort of hard to come by and only come in a few flavors 18 1/8" breaching barrel, 14" Short Barreled Shotgun, and 18 1/2" cylinder bore. Add differnat sight options and finishes you have it about covered. Vang Comp makes a +1 extension for it and I believe some of the Choate tubes will also fit.

In all I realy like their shotguns.