Gunsmithing Stripped Ruger 10/22 Receiver - Question about tapping.

[b7tac]

I stripped 3 of the mount holes in the top of my 10/22 receiver. One hole is stripped worse than the other two, but I think I stripped the other two to the point where they wont be secure for long. I am going to tap the holes to the next bigger size (from 6-48 to 8-40). I think it will actually be a little stronger with the bigger threads anyway.

Here's my question. Can I just tap the receiver over the existing threads, or is it necessary to drill first. I would think with how soft the aluminum is, it would be easy for the tap to rethread without drilling.

I wanted to see what you guys think before I do something else that I am going to regret.

 

[cal50]

ALWAYS use the correct size drill for the tap and chamfer the hole before tapping.

8-40 NS #28 drill (.1405")


Tap Drill Chart

 

[nzgrip]

What he said ^^^, especially with small taps like 8-40. Remember it's a lot quicker to drill a hole than it is to remove a broken tap.

 

[xringaccuracy]

Remember it's a lot quicker to drill a hole than it is to remove a broken tap.

Amen