i agree with deker ,short barrels are better for shooting from vehicles,standard lenght barrels are slightly quieter than short ones using the same moderator.heavy barrels are no more accurate in the field than standard but are more consistent if a long string of shots are fired,as for cleaning every 15 shots this particular myth has been responsible for ruining more than one 17hmr rifle barrel that i know of.i dont recommend this to others but i have carried out an experiment with my cz452 17hmr.ihave not cleaned the barrel for 500rounds checking to see if its going "off" every 50 rounds,,las