I have 2 J-lock Rem 700's, a .300 Win Mag and a 7mm08. Both are quite accurate hunting rifles and I've never had any issues with them. I'm not fond of the J-lock but it doesn't seem to affect accuracy on my rifles. However, I'm about to install Gre-Tan firing pin assemblies with a regular bolt shroud in both of them so we'll see if it makes any difference. My concern with the J-lock is that it could inadvertently lock up your bolt when you don't want that to happen.
