>What kinda ranges are we talking here, broke down in >rifle/pistol/shotgun ranges?
As said above - it varies quite a bit. I think the shortest range I've shot at was about 3 yds (with all three guns), and the longest so far has been: rifle = 200yds, shotgun = 110yds, pistol = 40yds. Most common is somewhere in between. What's been the hardest to get used to is the up close rifle shots and the long shotgun (slug) shots.
>Are there power factors like in IPSC?
Sometimes yes, sometimes no. I attended a match in which guys shooting .308 (like me!) only had to hit a target once to neutralize wheras guys shooting .223 (everybody else) had to hit it twice. It seems like pistols are always "power factored", but rifles only sometimes.
>I notice keepin the shotgun loaded seems to be the biggest >issue. How many rounds are we talkin?
Again - it depends. The most I've had to shoot on one stage was about 25, the least I think 3. Whatever you setup for "tactical" shell holding capability (side-saddles, butt cuffs, bandoliers, etc) you can pretty much guarantee somebody will come up with a stage in which you need more than you can carry, and you're reduced to fumbling around in your pockets for extra shells
>What shotgun loads?
Usually bird shot (4's and 6's are common) to preserve the targets. Buckshot is not allowed. As said above, clays and steel are common targets for shot. I've only been to a few matches that required slug shooting and selection, and they used steel and paper for targets. No pellet counts that I've ever seen.
>Is 3 gun more of an IDPA thing, more of an IPSC thing, or is it all >by itself?
I would say it's more of an IDPA thing. Most 3-gun matches are designed with an effort to stay "real." In fact - I make it a point to shoot "as I would carry" to reinforce that fact. My pistol is a G27 in an IWB holster (concealed, if it's cold). My rifle and shotgun are as stripped down as I can have them and still function well (no unneccessary bells and whistles) - the only exception is I'm a walking ammo-storage-unit at a match - cramming spare mags and shells everywhere I can fit them.
>Run me through a course you've recently done please, using all three guns. Gimme your gear setup too, like mag pouches, bandoleers, whatever.
Here's a "long range rifle" course of fire with some shotgun thrown in at the beginning:
We started behind a barricade with the shotgun (only 3 in the gun), had to hit 4 clays that were on stakes around 15 yds out, but the kicker was that a clay was thrown across the course as soon as you made your first shot, so you have to engage the flying target as well, all while reloading at the same time. Switch to slugs and make two hits each on two IDPA steel targets (maybe 50 and 75 yds), and hit a "bonus target" at around 110yds with slug if you have any left. Move to another barricade, retrieve rifle and hit each of the remaining eight targets twice each (all targets steel, scattered on the hillside from about 80 to 200yds) A few of them were 6-8" circles mounted on car springs, so they bounced when you hit them the first time (especially with a FAL) so your 2nd hit was on a moving target again. There were also IDPA-type, and some reduced IDPA-type. Any position is allowed, reload as necessary.
HOWEVER, that's only one example - they can vary quite a bit -
I've shot on the move, dropping, crawling through tunnels, from a car (through the driver's side window!), through ports, from a MOVING PLATFORM with a pistol, rifle, and shotgun.
You'll do reloads on the move, long shots (up to 200 yds), short shots, fast shots, slower shots, changing weapons with retention, leaving weapons empty, and on, and on.
I wear two rifle mags on my left hip, three pistol mags right in front of that (left hip also), pistol holstered on the right hip (pretty far back). For when it's necessary I'll slip two shotgun shell "butt cuffs" on my forearms to hold an extra 10 shells at the ready. That's part of the fun of these matches - figuring out what works and what doesn't as far as your gear goes. Think about what makes sense, try it, then don't be afraid to ditch it if it doesn't work out (you'll probably feel like throwing it!).
Good luck, and let us know how it goes!
Matt