View Full Version : Milling hardened steel (10/22 bolt)

12-19-2012, 03:39 PM
Im trying to mill a 10/22 bolt. Fairly unexperienced machinist. Tried using a standard cheap chinese endmill hoping it would work if I took really light cuts, didnt even scratch it before totaling the end mill. I'd rather not anneal it if possible. Will a carbide end mill work?

12-19-2012, 03:51 PM
Carbide might work in a very rigid machine. But why? The weight of the bolt is critical to the operation of the action. How will you compensate for the missing weight?

12-19-2012, 03:51 PM
If your mill is rigid enough it will work fine. If you have a springy hobby mill it will bounce around till the carbide is chipped to pieces.

12-19-2012, 03:55 PM
Carbide will work, quality hss will also work but quality hss will probably cost more than cheap carbide capable of doing the job.

Ruger has a reputation(at least with the gunsmiths I know) for having harder and tougher steel in them than most other guns.

What milling machine do you have?

12-19-2012, 05:39 PM

12-19-2012, 05:54 PM
I would try carbide on that machine. Do not try to climb mill though.

12-20-2012, 12:41 AM
I customized a 10-22 a few years ago which included milling on the bolt. I did it on my bridgeport with a carbide endmill with no problem at all. As always, watch your speeds and feeds. I am betting you had the speed way too high on your first attempt for hard steel. A cheapo endmill didn't help matters either.

Ron of Va
12-20-2012, 09:36 AM
I drilled a 10/22 bolt for the purpose of lightening it to shoot subsonic ammo in an integrally suppressed barrel.

The outer surface is very hard, but once you get into it about 1/16 of an inch, it drills just fine. I burn up the point of the first drill bit I tried. I slowed down, and used cutting oil after that. So once you get through the skin, it will go just fine.