Under gassed?

[Drifter]

If you open the gas port, do it carefully. Use a method to prevent the drill bit from going too deep. Put a wooden dowel inside the barrel also. You don't want to harm the rifling. It will likely require very little port enlargement. While it will hopefully solve your undergassed issue, you might need an adjustable gas block to curb excessive gas. You might lose a little velocity since more gas will be bled off.