I know that it is not a problem to seat out in a contender and seating down can raise pressure. Sometimes accuracy can be improved by moving the bullet closer to the rifling. I was not questioning the safety of your load, just to inquire about accuracy.
The C.O.L. that I was referring to is from the TC only 357 Max loads in the Hornady handbook.
The load that I was using last year for hunting was 18.5 grs of H110 under a Hornady 180gr SSP with a CCI 400 primer. Accuracy was decent, but I think it could be much better. I was not impressed with this bullet on deer, although it only went 50 yds.
Further testing this summer will be with 180 gr. XTP's and 180 gr. Remington HP's. I have not determined yet if my barrel likes the .357 or .358 bullets.
I did not test XTP's last year in 180gr but did shoot some 158gr XTP's with very good groups. I will not be using any more SSP's for deer.
That's one of the nice things about the max, there is a lot of different loads to try.
Heck, I'm even playing with 110 and 125gr varmint loads, can't wait to see how those shoot.