If it needed 6 screws, TC would have put them on there. But then again, TC isn't loading your ammo to your pressures. You may need 6 screws to keep your mount in place. If you do need to add two more screws, DO NOT attempt to do this yourself. LET TC or an EXPERIENCED barrel maker like SSK, Bullberry, etc add the holes for you. If you drill too deep, you will get into a pressure zone and can have some horrible results.
I have seen two burst Contender barrels. Both had the 6 hole bases on them. Both were re-chambered to larger diameter cartridge. Both peeled liked bananas from the chamber forward. You can imagine what happened to the base, screws, scope, etc. Shrapnel imbeds in soft tissue!
Be safe first and foremost.
Steve
