2400, 158 gr LSWC hardcast in .38 +P

Archangel my Lyman pistol and revolver manual 3rd edition I bought last year shows 5.4gr of Unique with the 358156 (155gr) bullet. That is a max +P charge. The max charge for the 358311 which is the 160gr RN is 5.3gr of Unique. I think that the reason that Lyman don't show data for a 158gr LSWC is because the 358156 could easily weigh 158gr. It just depends on what the individual caster uses for their bullet alloy. Lyman lists the 358665 RNFP bullet as being 158gr. However the ones that I've come across usually weigh in at 165gr.
I'm sure you're right about the alloy throwing different weights for the same mold. Like you said, the 160gr data is just as good for the 158gr bullet. I was making sure the data I posted wasn't misunderstood.
 
Bullets from the same mold will follow these rules:

Softer alloy=Heavier & smaller bullets.
Harder alloy=Lighter & bigger bullets.

The main point in any of this "difference in bullet" discussion really comes down to two things when talking about lead bullets, #1: Seating depth; #2: Bearing surface. I need to qualify that statement so as not to be misunderstood. There are other factors as well, none that will affect results MORE than these two.

I know, hardness, crimp and yada yada yada, will affect pressure too. None as much as the two mentioned above. Combine any two or three, then matters change drastically! ;)
 
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