[Brian Pfleuger]

The RSI system (linked by AlenJ) is nice but has it's quirks. (I have one.) The biggest hurdle is correct and accurate gauge placement.

There are companies that will test your ammo but (as far as I know) they all do it in SAAMI test barrels, which is to say not in your gun, so it really doesn't tell you anything that published data doesn't tell you, if such exists for your particular powder/bullet combination.

The other option is QuickLoad, which is a software simulation of internal ballistics but has proven itself to be remarkably accurate with bottleneck rifle cartridges and when properly "tweaked" to match conditions.