The hole is not blind as stated by GreGuy. It is as mentioned by JW a 1/4-28 screw.

The original screw is probably damaged on the starter thread. Replace it. Make sure it is the correct length.

If you tap the action be very careful. Us a small file or hone to remove the buggers around the hole first, then tap.

If you have to go up to a 5/16-24 NF or a 5/16-32 NEF Make sure you can get the screws in the length you need first.

As GrenGuy said, too long of a screw will interfere with the bolt rotation.

Next time, take a wood working clamp and squeeze the action into the stock before you install the screw.