Win 540 is now HS-6
Much dirtier then Auto Comp. I bought an 8lb jug from my gunsmith that he had laying around.
They used to use it to make power factor in 38 super etc back in the day. It still works it's just a dirty powder.
I'll use it for steel loads etc, not for major.
Oh, and yes you do need more 540 then Auto Comp to make the same power factor.
I'm using 7.8g of Auto Comp with a 125 Zero JHP and making 174PF out of my 38 Super.
It has 2 popple holes and a 6 port comp made by EGW.