JB weld is used to bed the base to the action.
I own a model 788 Remington 308. I wanted a picatinny rail to mount my scope on it. I was stuck with buying a EGW. I got it in 20 moa so I could stretch the 308 out a bit. I used JB weld to bed the base to the action. I used 8541 tactical scope base install instructions. Google will get you were to the site. I have not shot out past 300 yet as I have mot had time to get to a range any farther.
The reason why I bedded my base was the EGW did not fully meet the action with out a gap. I shot the gun before I bedded the base and it was all over the place. Talked to a friend and he suggested bedding it. Now it is a great shooter out to 300 so far.
Good luck and hope this helps