Todays 124 gr +P ammo has a WIDE range of fps speeds form all the various ammo makers, as well as pressures of their loads.
Bullet make up plays a large part on the fps, be it a all Copper bullet, a heavy wall copper jacket or the "plated" type JHP for one company, that ALL require a different fps to expand correctly.
If you get a chance, look up the loads on Luck Gunner, to see what I am talking about.
Lots of ammo to choose from, and see what your ammo is like.