Machine a Davidson base blank for an action???

[Phil]

What is the best way to machine an action radius into a Davidson base blank????

My action is 1.35" in diameter,but has unique hole spacing.

Phil.

 

[dalewoolumjr.]

There are several ways. I have used a boring head and machined the base vertically. Used Dan Lilja's method http://www.riflebarrels.com/articles/50calibre/scope_bases.htm. But now I am lazy and have a CNC so just 3D profile the radius in the base. All work well it just depends on the tooling you have at hand.

 

[rayjay]

Yep, bored vertically in the milling machine. I don't remember how I located the hole spacing hahhaha

 

[butchlambert]

Just screw some pins into the action and measure them. Won't the action manufacturer share the hole spacing?

 

[Phil]

Butch,

The guy`s who made my action are no longer in business,but that won`t stop me..... 8)

 

[butchlambert]

I would get a couple long screws and put them in the receiver and measure them or have your machinest guy do it.

 

[RandyB]

I believe the question was regarding the radius and not the hole spacing. RandyB.

 

[butchlambert]

Randy, You read better than I did. Why would you ask that question about the radius? If you are making a custom base you should have measuring equip. Mic the diameter of your receiver and divide it by 2. That will give you your answer.

 

[RandyB]

Butch, Yes Sir I know how to measure and determine the radius. I understood the OP was asking how to machine the radius into the bottom of the base to fit the action. It is something I have never quite figured out other than a ball end mill cut to dimension. Regards, RandyB.

 

[Phil]

Butch,

I appreciate your input on this.

My question, maybe it is worded to vague, is about what different ways people are machining a radius into a scope base.

I have all the measuring equipment and can locate hole centers. ;D

This is about using a Davidson base blank,not machining one from scratch.

I`m a welder, with only aspirations of some day becoming a machinist......just trying to learn something...

Thanks again,

Phil.

 

[rayjay]

Be sure and use a dial test indicator to verify that you have the blank base vertical. I also start with an undersized dia and work my way up. This allows me to experiment with feed and speed and tool profile to get a good surface.

 

[butchlambert]

I do it on a mill with a boring head.

I just started on the base shown. Crank in a few thousandths at a time.

A poor pic of the finished base.

 

[Jay Christopherson]

butch, not to derail the OP's topic, but where did that bolt handle come from in your pic? The engraving on that is pretty cool.

 

[butchlambert]

It is 2 handles tig welded together. Dans 40X welded the Pierce part of the handle to the bolt and then put one of his handles on the stub. Jerome Glimm did the engraving.

 

[Jay Christopherson]

It is 2 handles tig welded together. Dans 40X welded the Pierce part of the handle to the bolt and then put one of his handles on the stub. Jerome Glimm did the engraving.

Bummer, it looks like he's stopped checkering bolt knobs. Very cool detail.