I have trimmed case length so the ogive would not be set back in the neck and crammed 75 AMAX's to mag length. Then I was too chicken poop to shoot them.
I may need to do it just to say I had the Cahones.
77 SMK at mag length did not give me the accuracy the Hornady 75 HPBT did. This may have been because my barrel is 1/8.5, but I think that should have been plenty for 77's. I use 23.9 grains of RL15 for my 75's and pull 2675 at 90 degrees.
I will be trying to get this one to 750 really soon as my 30-06 will hit the smith for its' 6.5x55 rebuild. My ten year old carries this load to 500 on a regular basis.
According to my charts, it has a whopping 505 ft lbs at 500 yds. For comparison, my 30-06 smacks the snot out of a steel sihoutte swinger at 500 so much so that you have to wait for the swinging to stop before sending the next round. The 223 only makes it wobble like a fart in the wind. You see more bullet splash than anything to mark your hits.
My wife got some vids just Saturday of my son on the line. I need to get them from my wife and post em.