Same rifle. Same story. I find the 338 WM rather difficult to load for. Don't expect factory ammo to shoot well although it would be awesome if it did. I noticed my Ruger only had contact on one lug. Hey, it's not like Ruger's are Tikka's. I finally put a new stock (bedded + Limbsaver pad) and barrel (floated) on it. Still didn't shoot that well although it looked like it might want to at times. I want to use Barnes 225 gr. TTSX bullets so I stayed with that bullet throughout testing. It's very important to find the correct seating depth. Currently mine are seated @ 2.285" COL. The same bullet seated @ 3.330" throws 2-1/2" groups. Also the right powder is critical. The regular recommendations didn't work at all (4350's, H-4831SC, H-Hybrid 100V, RL-19, Varget, 7828SC, Ramshot Magnum). Varget was decent but about 300 fps to slow. 7828 SC was looking good but just as groups were coming in, the case wouldn't chamber because I crammed to much powder into it. Finally tried H-414 and things improved. If you have some Winchester 760 sitting around, it's said to be the same powder, just different labels. It has the same load data so I suspect they're nearly interchangeable but as always, work your way up. Here are my components for this load:
Barnes 225 gr. TTSX, Remington Case, H-414, Federal 215 primer (not match).
I just cleaned my barrel and loaded 6. First one was on paper (cold/clean), second was about and inch high and an inch left, the next 4 were stacked on top of the 2nd shot with 5 shots measuring about .6". I might be onto something. I then shot a second group of 6 with the same load but switching the primer to Federal 210M. The group opened up to 2+ inches. Change one component, maybe change everything.
My personal opinion is that generally speaking, if you want your 338 WM to shoot, you need to customize a load. Pick a bullet you want to use, pick a powder that might work, pick a magnum primer. I wouldn't get to caught up in the theory that seating the bullet as far out as you can will make it shoot best. Mine shoots best at just under a quarter of an inch jump. Since my rifles are for hunting, I load to use the magazine which usually means a significant jump. If you load beyond listed manual COL, be sure it's safe. I follow Bergers advice and load strings of 6 bullets in .040" increments with a powder charge about 2 grains below manual maximum (be sure that charge is safe). One group will shoot better than the rest. That's where you start your load development. You can fine tune seating depth later.
Although I know the changes to my rifle contribute to how well it shoots as of late, I wish I had tried to work up a load with 414 first.
