I've used some of the 6.5x55 ammo from Hot Shot, mostly just to obtain more cases for reloading for hunting ammo. I've found it to be very inconsistent at best myself,,so much so I gave up on even trying to use it to sight anything in. I went through 4 box's and never did get it to hit in the same place twice in a row!!! It drove me crazy,,and it's not the gun,,my reloads I used the next time out I was able it get it close within 4 rounds,and touching the same hole after 10 rounds, so it's defiantly not the gun ,scope or a loose mount.
In the 6.5 I can't say much good about it, other calibers , I couldn't tell you much sense I haven't used any Hot Shot in any other calibers. Keep us posted on the 223/556,,inquiring minds need to know!