I posted this to another thread, this is how it is done in Fast Draw for popping balloons at 18-20 feet should work for CMS
The Ammunition - There are two types of ammunition used in Fast Draw: blanks and wax bullets. The blanks are generally a mixture of black powders and pistol powders. Often (especially in competitions) the blanks will have a layer at the bottom of the shell that is made up of a combination of 4F black powder and bullseye smokeless powder. This is the kicker. The rest of the shell is often filled with a combination of grainier powders that will break the balloon. Usually this is 1F black powder and a grainy pistol powder like 4831.
What type of blanks are used in Fast Draw?
For practise I generally use a very easy to load blank. This consists of filling the .45 Long Colt shell all the way to the top with 1F black powder (very grainy). I then push a half inch circular stationary sticker just far enough into the shell so that the edges curl up and stick to the shell (you can find these at almost any stationary store). Many shooters use thin cardboard or styrofoam as the wad and keep it in place with a thin layer of nail polish. You don't want to fill the shell so that it's overflowing because you will then crush the powder when you push in the wad. That would turn your 1F powder into finer grains that wouldn't be as effective at breaking the balloon. Conversely, you want to fill up the shell as much as possible to get as much powder as you can. That way you'll have more powder flying out to break the balloon.
For competition I want a load that has slightly more kick to it, and possibly better pattern. I put about a quarter or a third of an inch of a mixture of 4F black powder and Bullseye powder in the bottom of the shell as a kicker. I tend to use slightly more Bullseye than 4F. I then fill the rest of the shell with a 50/50 mixture of 1F and 4831. The 4831 is a very grainy, slow burning powder that will not burn up before getting to the balloon. I then place the wad sticker on top. Every shooter has their own competition load recipe. This just happens to be the one I use.
By the way, most shooters in the sport use standard primers in blank loads, but most people drill out the flash hole in the shell case primer pocket. This tends to reduce the occurrences of primer back-out (which often happens with a blank), and helps speed up the ignition of the powder. You want to make sure that you don't drill out the flash hole enough that the anvil in the primer (the three pointed metal star inside the primer) can go through the hole. I've found that a 1/8 drill bit does a good job.
