Marlin 336 or 1895 base screws

[303carbine]

On these rifles ,I usually file the front screw a bit.
This prevents the screw from binding and creating chambering problems if it's too long.It's only happened to me once but that was enough to take the precaution of filing the front screw.

 

[gunrunner100]

A good idea when putting screws in any rifle is to place them in first, torque them with the action open and then try to close the bolt. Sometimes the screws are too long and prevent the bolt from opening or closing.
If in doubt on the length of the screw, take a paper clip and place it in the hole, bend it over once it reaches bottom (if applicable), then compare it to the screw. If it's too long, file it down and radius the first part of the threads.
When putting new screws in a rifle, use some nail polish remover or some other grease/oil remover on the screws and the holes. Torque and Loc-Tite as needed/desired.