256 Falcon 75 grain

I have a few boxes of 75 Speer HP bullets that I tried in my 257 Raptor barrel. I didn't find a load that it liked but would like to use the bullets to see if the 256 Falcon does. Manual has no listing for any bullets lighter than 85 grains. I'm sure there is a reason for that but has any Misfit tried it with success and if so would you share your loads? d p s j d j @ h o t m a i l . c o m