Apologies, but this is not really going to help now but I'm a stainless fasteners nut (excuse the pun) type of guy and use them where structurally safe. I have found 'dome heads' easily cheese because there isn't the shoulder material in the bolt head to support a torquing allen key / socket. Consequently they are used for low torque applications but often requiring thread lock as a result.

Everyone knows "right tool for the job" but quality keys will fit properly and reduce/stop the rounding out effect.

Disc bolts usually have a stepped shank so you can't just put any old bolt back in. Plus a "full cap head" allen bolt may actually contact the calliper when the wheel rotates.

In the past I have cut a groove in the bolt head with a Dremel and used a flat blade screw driver. If you've chewed the allen head out of it then that bolt is written off any way. You're going to have to order new ones and they ain't cheap. Easy on the hammer thing too.

Best of luck.

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I have a lot of growing up to do. I realized that the other day inside my fort.