I have an SWR 'Spectre' Can and was wondering how often folks clean theirs? I usually clean it 'totally' after every 400-500 rounds, though I do run some brake cleaner and a .22 Bore Snake through it after every use. Is this frequent enough, or is it based on the type of ammo used? I fire it with a Walther P22, A GSG 1911, 10-22's and a Spikes Tactical .22LR Upper and also a couple of .17 HMR2 rifles. Thanx for your input ....