Blind Tapping

[tikka308]

Beginner question here regarding tapping...

Is it possible to blind tap a hole? Most of taps I've used don't fully-tap the bottom ~1/2" of the tap, and thus for a blind tap, I would have to drill the hole about 1/2" deeper than the tapping threads? Is there anyway to avoid this and have a blind hole that is "fully" tapped?

[Ken_Shea]

You can get pretty close using a bottoming tap. All taps have some lead on them which prevents fully tapping a blind hole.

EDIT:
Never done it but you may be able to start the tapped hole with a conventional tap and then carefully grind most of the lead away and finish with that.

[tikka308]

Ah - bingo - "bottoming tap" must be the type i'm looking for. if I'm manually typing (i.e. by hand), should I first use a standard flute tap and then chase it with a bottom tap or can I do the whole tap with a bottoming tap?

[Ken_Shea]

tikka308 (great rifle BTW)
If you are hand tapping you may find it a little easier to to start with a standard tap. Really depends on the size, setup, material and experience.

Ken

[tikka308]

Ken - thanks!

You a shooter? My Tikka Sporter with 168bthp has to be one of my favorite combinations ever...

[Ken_Shea]

Have a gun store and very familiar with these guns, used to shoot a lot, not much time any more, need to make time, shooting is a world of fun.

I'm not much of a hunter, used to be, can hardly kill anything now, don't get me wrong, I am not anti-hunting, wrong business for that, hunting is esential to many animals existance. just not for me any more, I still like to kill targets though

[tikka308]

Good stuff! Where's your store? I'm actually not a hunter at all - just a long range competitor. I gather you're probably familiar with this - but many folks don't realize the similarities between long range competitive shooting and machining.

what kind of machining work do you do?

I see you're from Ohio... I grew up in Zanesville - about 60 miles east of Columbus on I70...

[Ken_Shea]

Precision machining or long range shooting is not done by accident, it takes practice and skill.

My store is about 45 miles due north from Columbus on St Highway 42.

My machining is quite varied, from gun related (my favorite) to machining things I have no clue and am not told what they go on.

I do not consider myself a machinist even though I may tend to under estimate my abilities.

Doubtful there is a better bullet for the 30 cal then the 168gr BTHP.

One of the most unlikely and surprisingly accurate short range bullets that I have shot is the Speer 30cal 110gr HP.


Ken

[tikka308]

What barrel twist are you pushing a 110gr though?

Hmm, the only thing I know north of Columbus is Fin, Feather & Fur...

Are you running CNC or manual?

[Ken_Shea]

It has been quite a while back and I do not recall the twist, barely recall the gun, think it was a Savage but I was very suprised, that is why I still recall it.

Fin Feather and Fur is kinda a mini Cabela's, which I am neither

They probably have more in boots then I have in inventory

Milling with both manual and CNC mill , manual lathe.