I go about every other week. If I'm shooting either my 9mm Para or 9mm Makarov, then 150 rounds per gun. I run through failure drills, practice hammering the target with a full magazine as fast as I can acquire sight picture, point shooting, weak hand, etc. Ranges don't exceed 15 yards for that. If I do well in all aspects and don't have any need to correct what I'm doing with close-in stuff, then I'll take the target out to 25 yards and do some accuracy shots with whatever ammo is left.
When I take out the .38 snub, then it's usually less than 30 rounds in a single sitting. Anything more that I start leaving blood and pieces of skin on the gun and practice starts becoming counterproductive. With the little revolver, I never shoot past 10 yards and about 2/3 of the shots are done weak hand only. I do want to eventually get a set of CTC grips for this one and see if I can extend my range and accuracy with this piece.