I have that same stock on my .338LM since around 2010. When I bought it used, supposedly with only 50 rounds on it, it tested out like shit as received. Like 2-2.5” groups at 100y. And no, it was not me Magnum or not.
I pulled the rifled action and found significant marks on the left of the front block and the right of the rear block. Having never bedded a stock up until then, I knew that’s what it needed. I read up on it, made sure I had what I needed and bedded the action to the stock and ‘chassis’ blocks.
I am not kidding to say that groups went to ragged holes at 100y with 285g BTHP.
Okay whole story. At the same time since I had the stock off, I used a hack saw and then the blade wrapped with a tape handle, to cut in an adjustable cheek piece and also add 2.5-3# of lead into the back of the butt (using marine tex). As received, the rifle was unbalanced and front heavy. I like a balanced rifle that I can shoot from Stamding unsupported if needed/wanted.
If I hadn’t already decided that this was a budget ELR precision rifle, I would have added an adjustable buttstock. As is, it is totally red neck and yet fits me and shoots.
View attachment 8166730 A thirteen inch 3-shot consecutive group at 1840y in heavy mirage. Yes, with S&B PMII, Verified on camera. Off of an elevated platform on a pickup truck.
The extra weight in the butt balances the rifle perfectly and changes the recoil substantially. For even a better recoil impulse, get a suppressor. It changes the recoil to a push instead of a punch and reduces muzzle blast considerably. A totally different experience.
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