Drilling and tapping

[yotebuster]

Anybody ever do this on your own? This should be a really simple one. I have a Winchester model 70 that has two holes with proper spacing on front and only one on back. Spent an hour on the phone with leupold trying to find a one piece base that will fit it so I don't have to drill a fourth hole and their best suggestion was to drill another hole on the rear and use their two piece base. I should be able to mount the rear base and torque it down and mark the hole with a punch easy enough so lining it up will be simple. I'm just scared to do it. The nearest smith to me here in BFE North Dakota is 2.5hr drive. I tried to retap a stripped out 10/22 receiver in high school and did a horse sh1t job of it but that is a soft aluminum receiver. Not sure if steel is easier or worse?

[firstcoueswas80]

Why not research going with a different type of Base?

[Kaffer62]

Do you have a drill press? Drilling a tapping generally isn't the hard part. Making sure your measurements and depths would be the more critical aspect of it.

[AzPlumber]

I would check with a local machinist. A threaded blind hole takes a bit more expertise and tooling.

[yotebuster]

Why not research going with a different type of Base?

I have. No one makes a one piece model 70 base that has the proper hole spacing. I'm thinking this gun was drilled after the fact as the spacing doesn't line up with anything leupold could find.

[MULEPACKHUNTER]

I ordered a one pc minus the holes from egw and drilled holes in base myself.

[mattys281]

 

Why not research going with a different type of Base?

I have. No one makes a one piece model 70 base that has the proper hole spacing. I'm thinking this gun was drilled after the fact as the spacing doesn't line up with anything leupold could find.

What thread is it? I might have everything you need laying on the bench in my shop.

 

If you want the hole in the right place, square, and with good size threads (not wallowed out) you need to a.) Spot drill it, b.) Drill it) and c.) Tap it using a tap guide of some sort that will keep it all in line.

 

Or d.) You can bring it and a six pack of beer out to Avondale some evening after work and we'll get you squared away.

[yotebuster]

 

 

Why not research going with a different type of Base?

I have. No one makes a one piece model 70 base that has the proper hole spacing. I'm thinking this gun was drilled after the fact as the spacing doesn't line up with anything leupold could find.

What thread is it? I might have everything you need laying on the bench in my shop.

 

If you want the hole in the right place, square, and with good size threads (not wallowed out) you need to a.) Spot drill it, b.) Drill it) and c.) Tap it using a tap guide of some sort that will keep it all in line.

 

Or d.) You can bring it and a six pack of beer out to Avondale some evening after work and we'll get you squared away.

Man I appreciate the offer and would take you up on it in a heartbeat but I'm in ND! I should fly down there anyhow just to get out of the cold!!! It's the standard thread that leupold bases are (6/48???)

[mattys281]

 

 

 

Why not research going with a different type of Base?

I have. No one makes a one piece model 70 base that has the proper hole spacing. I'm thinking this gun was drilled after the fact as the spacing doesn't line up with anything leupold could find.

What thread is it? I might have everything you need laying on the bench in my shop.

 

If you want the hole in the right place, square, and with good size threads (not wallowed out) you need to a.) Spot drill it, b.) Drill it) and c.) Tap it using a tap guide of some sort that will keep it all in line.

 

Or d.) You can bring it and a six pack of beer out to Avondale some evening after work and we'll get you squared away.

Man I appreciate the offer and would take you up on it in a heartbeat but I'm in ND! I should fly down there anyhow just to get out of the cold!!! It's the standard thread that leupold bases are (6/48???)

 

 

 

I get cold just thinking ND in February.... no thanks!

[yotebuster]

I would check with a local machinist. A threaded blind hole takes a bit more expertise and tooling.

.

 

I'm gonna check with a machinist. The hole on my other model 70 (that I know is factory drilled and tapped) goes clear through on both rear holes so it should be a fairly easy hole for a machinist to drill.

[AzPlumber]

Hopefully you have a local Machinist, should be a quick and inexpensive job.

[300RUM]

There is no reason for the hole to be blind unless it comes out over a locking lug for the bolt.

 

If you can get access to a mill or at least decent drill press you could do it, If you really want to. Find a drill bit that fits snugly in the hole on the base. Mount the base on the action with the other 3 screws and clamp the action to the table level. Place the snug fitting drill bit in the chuck upside down (flat end down). Use the bit as an alignment gauge to center the hole under the chuck. Tighten everything and recheck the alignment. Spot drill to start the whole then drill up to the correct size drill for the tap. Use the chuck of the drill press to support and align the tap & tap handle. Tap slow, back out frequently and clean and lube. The Action is going to be hard and it is very easy to break off the tap. This is a problem that requires special drill bits to resolve.

 

The reality is that unless you already have the tooling it is probably cheaper and much less hassle to have a machinist do it.