Well now, since ya axed the question, I'll tell ya what I do. When I venture out shootin along my favorite shootin spots, a lot of the time in a wooded pasture with a river runnin through it, I carry spare ammo in a variety of ways. Sometimes wearing a pair of green camo bibs, as Delmonico penned, "the original tactical britches". Sometimes wearing one of my several pairs of military BDU's with all those wonderful pockets. Usually have several bandoleers slung crossways across my upper torso and/or a belt with loops around my waist. Something I found handy years ago while a LEO were M1 Carbine double ammo pouches. These neat little green pouches are perfect made for all the HXS speed loaders I used for shootin double action .357 (and any DA revolver). They hold two ammo loaded speed loaders perfectly. Used to strap around six of them all loaded up around my waist. Now please don't get all jumpled up saying "Hey this is a old timey forum, not about modern handgun shootin". They work, I've even put six loose rounds of 45 Colt in each space, ie 12 rds per pouch.
I bought several Russian Mosin-Nagant rifles 7.62x54 rifles for my WW2 military collection. Ugliest gun out of all that came out of that era (IMO), but they're shooters. Anyway with every gun came a Russian ammo pouch, you've seen them. Great ammo carrier, even use them to carry balls and wads when shootin my cap and balls. Bought a few extra for slingin through a belt and strappin around my waist. Old 12 round slide ammo loops from my LEO days are pressed into service when shooting 38/357 guns-even employ a 38/357 double ammo dump pouch. Around the waist loops are used also. Cooler weather brings out my old Vietnam era green Army jacket with its spacious pockets. A cross chest heavy duty camo condura pouch that has a lot of room for all kinds of ammo and whatever is sometimes used. Back in the early days, I took an old leather white purse of one of my sisters, dyed it black and it was slung on me along many of shootin jaunts in thee ol sandpit we used to shoot in, river bankin shoots, huntin expeditions, etc. Used to get a lot of razin' about it from friends, but they were always glad I had it when they needed some of the various things besides ammo I carried in it. Water bottle, screw drivers, gum, hard candy, chew of RedMan, etc.
Sometimes I just keep it simple, wearin nothin but a pair of bluejeans, stuffin as much ammo in their pockets as I can, and go plinkin, usually wish I had brought more. I like this shootin over any paper punchin, stage shootin, or any other. Very fun and relaxin. OK, this got longer and more wordy than I planed. Back in the 60's-70's a country music player by the name of Tommy Collins, wrote and recorded a song called "Remember Opal, You Asked Me" about a guy telling his wife why he was leaving. A comic list of reasons, its on the web (You-Tube) if your curious. I know it's not something to make light of, but Collins wrote/recorded a gem. OK, I'm done, I know some of the items I carry ammo in aren't cowboy, SASS/NCOWS approved, period correct, etc, etc, but they work and as in the song--- "Remember You Asked Me"!