Anyone come up with a action Cycling Subsonic Load yet

[GregP42]

I was out in a gun shop about 100 miles from home last weekend, and I found two boxes of the .264 160gr round noses. I can seat these out a lot longer in my Grendel and was wondering about a starting load with these. I am using a m16 bolt carrier and A2 buffer and tube with an 18" barrel on my rifle. I will be using IMI brass with CCI #34 primers. Since I have never tried any sub-sonic loads before I thought I would ask here if the loads you worked up with the .268 bullets would be ok to start with in my rifle.

Thanks,
Greg