Well, for what its worth I've probably had Karl do at least a dozen bolts for me, all with the smooth Campfire knob. I'm guessing the 1st one he did maybe 5 years ago and so far I've never had any issues with any he did. I can say I've saved smashing my knuckle on the scope when running the bolt a few times since the knob gives a little more clearance than a factory one.
