Arrrrg, just accidentally deleted entire pre-written post. Ok take 2, probably going to forget things. Main statement I'd like to make is
my on-person round count is directly proportional with how far I am going to be traveling from my home. If I am less than three miles from my home I will be more inclined to have a fully loaded gun with one reload on my person. 9 out of ten times this is my SW1911 with one in chamber 8 in chip mccormick, and one ten round chip mccormick on my person. If I am looking at ten to 20 miles or so from my home I'm likely to carry three additional S&W 1911 mags in a 'smart carry' aka thunderwear. Basically I have no reason to expect trouble, but I do NOT want to kick the bucket early, or worse yet live the rest of my life wishing I could have saved someone and hadn't been able to due to lack of ammo. Also, you never know when you'll get a chance to plink a few, so I like to have a mag of FMJ either as one of the three in the smart carry, or whenever I have a backpack, just in case a safe, fun opportunity arises. If I am traveling in excess of 100 miles from my home (and arsenal!) I will usually bring the 12 gauge, thoroughly locked and unloaded, usually well-hidden, perhaps even with cable lock through action AND trigger lock. Also have a bandolier of 00 buck, 000buck, hollow slugs and long range slugs that goes where my shotty goes. This is basically in case the world as we know it decides to drastically change for whatever reason. I'm a firm believer in Murphy's law, I try to take it into consideration as much as possible without letting it ruin my fun

My most common carry is my SW1911. If my clothing permits, I also carry a beretta .32 tomcat loaded with JHPs and a bag of a few extra rounds easily fits in the pocket of my smart carry behind the 1911 mags. In the winter I sometimes switch to my Ruger gp100 in a shoulder rig, with a total of three additional speed loaders, one in each side jacket pocket, and the third wherever is ideal. This is for comfort and because a winter jacket makes it easier to conceal. Also sometimes because my 1911 is filthy and/or soaking in oil after a good shoot.
i have one s&w factory 8 round mag fully loaded with golden sabre .45acp jhps that just stays in my car at all times. it's the 'i really hope I never need to use this' mag