Okay, went out this past Sunday, and shot up the ammo I'd loaded.
I started with the minimum load as stated by the Sierra 50th Anniversary reloading manual, using the 69gr Sierra Match Kings, IMR 4895, and Hodgdon's H335.
I had 3 different loads for the 4895...I increased by .4gr each load. Same for the H335, but I had enough bullets for 2 different loads.
The 4895 did the best with 23.4gr, the groups tightened up really nicely to between 1/2 and 3/4"...but 3 of the 4 groups had a flyer...I was shooting between 2 guys with FALs, and each time one of them fired, it would knock my POA to hell...so I had to kinda squeeze my shots off in between the two of them...not the most ideal conditions.
The H335 did okay, both loads around an inch, but never got any better. So far, it looks like the 4895 is the way to go.
Next batch of bullets, I'll start from the 23.4gr and see what happens from there. Also, the trigger in this rifle was atrocious...actually painful to shoot after about 40 rounds, I could feel that one tendon in my carpal tunnel being strained. When I got home, I tweeked it...it's much easier to pull now, and I'm sure that will help tighten the groups up as well.