Thread: Grouping problem 338LM

I would check to see the brake is tight & shows no sign of getting in contact with the bullet .

It seems you have checked all screws etc , I would pull the bipod off and fire it off sandbags front & rear , and also use the free recoil style of shooting IT , BUT be aware that you may have large groups at 100 & at 500 they are much smaller moa relative , I think some times it takes the big pills a bit longer to settle down .
In a Sako TRG-41 , I found it was not that impressive at 100m ( approx 1 moa ) , but at 500 it was sub 0.4 moa ( 2.25 inche groups ) , just some thing to think about .

Later Chris