d.i.y. fluting/dotting bolt ?'s

[logic factory]

i have finally purchased my one rifle for life and knowing that it will be several months before i will shoot it i have began my personalizing of the action. i ended up making a jig that allowed me to center punch the 72 holes i plan on adding to the bolt with an acceptable consistent spacing.

i understand that for very hard material one needs to keep the drill bit cool; this should be done by running on a slow speed and using some sort of fluid to keep friction down and disperse the heat being generated. having said that i have not been successful yet with the one cobalt bit i have bought; 1/4 inch with a smaller steeped nose.

here are my next tentative plans that i ask for critique on:
1. buy another cobalt bit that is about 1/8 or a little smaller and using this to dig a little hole that i can then use for the larger bit.

or

2. the few times i have made some decent progress with stainless steel i used some sort of burring bit which lead me to my second option. seems like some literature i read suggests the use of tungsten burr bit.


im leaning more toward option two at this time.

what say you?

the end result should look similar to how twistedbarrel.com does their dots.
image taken from their website.

[keeki]

carbide requires high speed (850sfpm) with quick jabs to keep it cool. Run that drill fast, just dont stay in the metal long and use fluid. Or you can get you some 1/8" shank carbide cutters.

[keeki]

if those cutters you have in the post are carbide they will work fine

[ellobo]

if those cutters you have in the post are carbide they will work fine

+1 on the carbide. The bolt sleeve is hardened enough to make cobalt drills tough to use.

El Lobo

[logic factory]

thank you all, for the vote of confidence and correcting my speed for the carbide burring bit.
i will look through the burring bits i have and wont mind buying a new carbide one on the way home from work tomorrow if i have to.

[sharpshooter]

A single flute carbide drill would work better. The carbide burrs have a shallower relief and don't cut well from the end. The hardened case on the bolt body is about .020" deep.