use the same data for jacketed bullet, velocity will be close to the jacketed but pressure will be lower.
if you have data for next size up, its ok to use data from heavier bullet but not the opposite, LEE Reload manual #2 is full of good reading
NOOOOO! use specific data for the bullet. Using jacketed data in a blowback pistol lke a 380 and a cast bullet will give substantially more velocity and can cause problems. Pick up the Lyman manual. They have a bunch of cast bullet data
In life, strive to take the high road....It offers a better field of fire.
"Robo is right" Fuzzball
Cast bullet loads require their own data. Lee and Lyman typically have good cast bullet loads. It seems to me Lee has a fairly good selection of loads for the 380 and cast bullets. I'm at work so can't check that.
no if you use jacketed data for cast, the velocity will be the same but lower pressure
check with any of the guys on castboolits.com
I have used that rule for 20 some yrs,never hurt anything. I shoot 454,45-70,204 ruger, and 223
the guys at cast boolits site have tons of insight on cast boolits