Slick way to cut a picatinni blank to fit the action?

[LPC]

Small ring Mauser, I haven't found a mount base for it yet and it looks like machining a bank to direct fit the action is maybe the best bet. Someone have a slick idea I haven't thought of to cut that ~.65" radius so I won't need a ball em ground? I'm drawing a blank for something to do a 6+ inch long cut.

 

[Gord0]

You could set it on an angle plate in the mill and use a large adjust boring head. It'd be an interrupted cut so you'd want the biggest bar you could get to work, but it would work. You could also make a setup to do it in a lathe with a boring bar. A CNC could surface it pretty quick. One with a smaller or larger rad could be bedded with devcon.

 

[Wado]

I use Farrell bases on my 98 actions. They offer them for Small Ring Mauser as well.
https://www.kenfarrell.com/index.php?route=product/product&path=20_60&product_id=211

 

[concordshooter]

large radius cutter calculation

sin C = D/2Rc

where C = angle of cutter with axis of work surface
D = cutter dia
Rc = desired radius of surface

std flat btm end mill can be woodruff cutter or carbide router bit
obviously cutter must be larger than radius desired
Bridgeport mill angle head 90deg -"C" --- c is angle from work piece not angle from vertical of head

been a while since I've done it and takes some trial and error to get figured out but does work, mauser's tend to be off slightly anyway so best to cut close and plan on bedding base to action for best fit. I believe EGW makes a small ring mauser base, undrilled best bet if allready been drilled, unless factory or your sure holes will match.