Subsonic 125g or 150g

[Pitt300]

My 300-221 is finally coming together & i pick up my can tomorrow.
I have 125g Nos BT & 220 & 240g SMK loads that I'm working up for me.
I'm cheap & I have a number of people that already want to shoot my new toy.
I can buy either 125 (500 for $65.99) or 150 g Remington (500 for $70.99)PSP bullets pretty cheap from Midway.
Has anyone loaded these subsonic w/H110 or another powder?
I thought these would make a cheap cartridge for me to let my friends blast & keep the good stuff for myself.

[pug]

Not sure which brand you have but my 16" will start cycling at 8.2gr of H110 with a 150 FMJ. Starts going transonic with a hot barrel at 8.5gr. Little bit of room to work with but not much.