doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Drilling butt stocks for through bolts

Start from Square blank is best. Go at it from the butt plate end with a Frosner bit large enough hole to accommodate whatever bolt & washer and more important driver bit you will be tightening with. Then go deeper with a regular twist bit, far as it will reach. Then use the same twist bit from the action end. Now you have to get out the center. Not a lot to be taken out Home Depot bell hangers bit will do it. but a home made gun drill is better. Just takes time to make one up. If so use the bell hangers bit to make the gun drill.

I use the wood lathe with the blank supported on a drilling table held in the steady rest base. Could use the machine lathe but don't like wood chips all over it. If you don't have a lathe use the drill press, it's just as good if set up right. Put a small tube in the chuck run a plum bob through and index on a board with protruding screw clamped to the table. Most drill press quills don't have enough travel to go all the way. Not far to clean out the center and nobody sees inside the center of the hole, you can finish with a hand drill from both ends .

If I had to drill a finished stock would make up a plywood box to clamp it firm and give square sides to index. Finished stock is risky better make the start holes perfect

Boats

I use a forsner bit for the large hole with extensions as the hole deepens and a brad point bit from the action side. I set my drill press up with a point in the 4 way vise and make sure it is in perfect alignment with the machine head. Put the point on where you are going and know where you are starting from. Be careful on the web you leave between the action and large diameter hole. If you make it to thin the through bolt will interfere with the inertial block and the gun won't function. I also try to use a few Bellville washers behind the bolt head to compensate for any crush of the wood during use.

bill

Good tips, Lot of how you do it depends on the bolt to be used, how long what size. Most of the time using the drill press I index the table end on a lathe center dropped in a drilled in plywood hole. That way when reversing the index is fat enough to find center in the Frosner bit hole.

If the job to be drilled is under about 36 inches almost always use the lathe. Not any better just faster to set up.

Boats

Here's the one I use, .375 diameter; some guys leave the tip much flatter but I like a bit of an angle similar to a regular drill. The flute is about 2" long.

Craig,
Thanks for the images. Is a cutting edge applied or is the tip of the rod simply shaped and then the quadrant is removed with an end mill?

You are welcome. The end of the drill is relieved by grinding/filing just like a standard drill; the "lip" on the bottom in the first photo becomes the cutting edge.

Craig

Craig what kind of stock did you make the drill out of ? Harden it ?

Boats

Yes, I think it was O1 or A2. Hardened after milling/grinding and then stoned to polish and keep sharp.

The depth of the milled slot is exactly half the diameter of the drill in both planes.

Craig

Craig,
Thanks for the drill information. Got the drills made early in the week and got the hole in. As you can see a modified gun drill design was used for the 5/8" part of the hole and it uses a 5/16" pilot for guidance. I used O-1 drill rod and hardened before use.

Here is the final result with the action inletting completed:

Very nice, Dennis; glad it worked out. Beautiful stick on the Martini as well, love that random marbling.
Craig