Originally Posted by tinkerer
Everything I know about pistol reloading:
A. For semi-autos, they don't like roll crimp, they like "squeeze" (wrong term) crimp.
B. AFAIK, one seating die, properly adjusted, will work for "most" rounds.
C. Invest in carbide dies, they work better.
D. Check each and every cartridge for proper powder throw, no double or light charges. Both are bad.
My sum total knowledge I bequeath to you, grasshopper.
+1 on Larry's comments
A taper crimp is the only way to go for a semi, but I'm not sure if your 38 super dies will have the roll or taper crimp die. If they are new they will be a taper, but if they are older/used the die MAY be a roll crimp.
The reason, the 38 super at one time was assumed( and made to) to headspace on the pathetic semi-rim it has. Newer pistols have better chamber tolerances and will headspace on the case mouth; hence why the crimp style has changed for this caliber. Better accuracy with more positive headspace with the taper crimp assuming a good snug chamber.
Make sure you are a couple of thou. under flush with your seated primers also as you COULD slam fire the pistol otherwise.
I've never loaded the 38 super but have played with the 9mm luger a good bit many moons ago.
As far as seating plugs for different bullets; same as for rifles; usually one will do all, but occasionally you'll need a different one. I have both rn and fp punches in my 44 mag dies.