Well folks, live and learn! I've been wrestling with a Howa 1500 .338 Winchester I picked up used several years ago. I could never get it to settle down...until today! I restocked (from "Tupperware" to a Boyd's laminated JRS). I glass bedded/free-floated. I recrowned. I full-length bedded (after which, the gun became more consistent...but hardly a shooter). Most recently, I've bugged you guys about adjusting dies to headspace on the shoulder instead of the belt. I even bought a Stoney Point OAL gauge.
After neck sizing, the gun would shoot consistent 2" 3 shot groups @100 yards. Well, O.K. Certainly good enough to hunt with, but I was really hoping for something a little better. Then, as I was rereading Brian Pierce's .338 article in the Feb. '07 issue of "Handloader", I noticed that he mentioned loading close to max loads. (I'd been loading a mid-level receipe of H4831). So I thought, "Let's bump up a notch and see what happens." Just before lunch, I loaded three rounds with ONE GRAIN more H4831. Then I ran out to squeeze off the experimental rounds. Results: An honest 1" 3 shot group!
After work, I ran back to the bench to load three more. I had to see if this was a fluke or maybe a breakthrough. Results: 3 shots that measure 5/8"! And here's the thing, both groups landed in the same 1" square on the scope target (different targets/same square). Imagine that much difference from moving up ONE GRAIN!
I'm almost afraid to put this in print, but I think I've finally come to an understanding with my "problem child" project.
Now, if I can just find some really big prairie dogs...