Figuring fps

[northmn]

As others have mentioned you need a chronograph. Some loads in manuals seem to be a bit optimistic. I have seen some intriguing differences between published data and actual loads. If you depend on published data for the math and its not right, neither is the math. Garbage in garbage out.

I have loaded more than a few loads without Chronographing them an gone out and enjoyed shooting them. Unless one is in competition where there may be maximum accepted loads or something like that. Load a few and shoot them and see if they meet your desires.

DEP

[KWK]

He stated up front he only wants an estimate for the charge to start with. Wanting about 1550 fps from a published load that nominally might give 2390, he’ll want to start at 65% of that max charge, or about 22 gr. Then adjust charge to reach the desired fps on the chronograph.

[Geezer in NH]

I use a Chronograph and get real time info. Mines cost 99 bucks 20 years ago and has been rebuilt twice under warranty for cost of shipping. Best money I spent for reloading.