I have 2 rifles with Mil dot equipped scopes and I'm still in the process of verifying the bullet drop out to 1000 yards with the loads I use, so I don't actually use the Mil dot to it's capability yet. I want to get to where I can use it to range a target, figure the hold over (or under as the case may be) and just hold over for the long shots rather than adjusting the elevation knob. I know there are scopes with built in BDCs, but if the load is not exactly the same as the BDC cam then out at really long range the difference in POI could be off a fair amount.

Anybody else actually use a Mil dot scope the way it was intended? How reliably can you hit using it for hold over?

I have mildot scopes on my important rifles.  You can use it to range objects of a known size, although I rarely do that, having the advantage of a laser rangefinder.  I could give you the formula, but I don't remember it, and use a handy little slide calculator called a MilDot Master (get one if you are serious about mildot reticles: www.mildotmaster.com to figure things quickly.  As far as using it as a BDC, I can use it fairly well to about 500 yards.  You have 3.5 moa between the centers of each dot; therefore you have 17.5 moa from the crosshair to the top of the lower post in the reticle (5 mils).  Accurately using it depends on knowing the exact muzzle velocity of the ammo lot you are using, but as a SWAG, use this formula for a 100 yard zero:
200 yds= 1.5 moa holdover
300 yds= 5.5 moa
400 yds= 9.5 moa
500 yds= 16 moa

You can increase this ability by zeroing your rifle at longer distances; I believe Marine markmen zero for 600 yards, effectively raising their mildot use to something like 1200 yards.  However, using mildots as aiming points is always secondary to having a good range and manually dialing in the elevation on the scope; you can't see the subtle differences a few yards in distance can make in elevation correction on the mil scale at longer ranges under most field conditions as well as you can dial them in.

Leupold's website also has a mildot reticle explanation page.  I hope this rambling helps;
good luck!

I have two of them, and I find them quite useful.
One is on a Ruger M77VT in .223 and the other is one a Ruger M77VT in .308
Both rifles are quite accurate and for each I have ballistic printouts (courtesy of the Lee Shooter computer program) of their primary loadings. I have found actual ballistics to be quite close to projected numbers.
Combining a mil-dot scope with ballistic tables and of course a laser rangefinder and you no longer have any excuses for a miss.
Loads of fun too, do your part and you should be able to outshoot just about anyone.

Check out the demo on this site. I think I'm gonna go ahead and get the cd.
www.shooterready.com/lrs.html

I know and understand how the Mil dot system works, and have the Mil dot Master booklets. I've also practiced using them to determine distance to objects. I was just wondering how many people really know how to and/or use them, because I think a lot of people just get them because they are "cool".

BTW, today at our LR Tactical match I was talking to the guy who won - shoots a .300 Winmag - and he uses the MIl dots exclusively over the course for el and windage even though most all the course is known distance.

I don't currently own one, but I plan on getting one once I get a serious bolt-action .308 (I'm thinking a Rem 700 VS).  I like the idea of a rangefinder that doesn't run out of batteries.  The math is pretty simple.  (Height of target in mils*1000)/Height of target in meters=range to target in meters. Mind, that's for a fixed 10-power scope.  If you use a different power, you have to divide the power by 10, and multiply that number by the range in yards to get the true range.  If you get really bored (as I did on a lazy day fishing), you can re-work the math and convert it into inches, so you can use mil-dots to find the range to a 10-inch tall prairie dog instead of a 2-meter human.  Then you can memorize common measurements with the dot scale (and memorize bullet drop for the load you're using) so you don't have to look at a slide-rule.

Don't mind me, I'm just sitting here dreaming about what I'm gonna do once I get a good rifle.