If you are going to use this stuff a chronograph is a must. If you have a load for H335 that you use and you know the velocity of that load.(as tested by you)
Then just load up a run of wc844 loads, Maybe 3 each from the starting load, going up 1/2 gr per 3.
Then run them across your chronograph. When you get to the one that matches your velocity. Stop... Thats your load.