I am using two different loads of HS-6 in two different open guns. The with poppel holes I use 125 gr JHP with 8.5 gr of HS-6. The gun with out holes I use my 8.1 gr of HS-6.
I talked to two different open gun Gurus from two different ares before getting in to open, and they both had the same opinion that HS-6 has an easier pressure spike and is less likely to do damage to the guns. One had over 75,000 rounds with no crack to the slide and the other had almost 125,000 with no crack to the slide. They both also said the same thing about auto comp, that it has less felt recoil but has a sharper pressure spike, and most cracked slides they saw were when using it.