Help solve complex math problem... reward if found.

According to Borden's drawing above, if you have one of the actions listed with a magnum bolt face and no recoil lug.
Again, you want to make sure your compound has enough movement to completely cut the cone. Then using the cutter your going to cut cone with (I use a carbide boring bar) you need to zero Y at your shoulder and set the measured dimension of tenon in X. If you move to 0.9 in Y, over to 1.003" in X and lock down carriage and use the compound, that should match their drawing. Now realize, you can't start at 1.003" and start cutting. You'll actually start closer to either bored hole or chamber wall. Then you'll be working X back to 1.003". When you get to 0.705" X in diameter mode, your Y should be 0.814". Now here is the unknown, I don't know what bolt nose clearance that leaves you with. The drawing doesn't have that. But since that last drawing above is guide for a CNC machine, I ASSUME that puts it mid-spec (.005"-.010"). I'd do a test tenon and verify dimensions match old barrel using same tools to measure both.

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Yeah... after I typed my last message, I realized it gets tricky with a tool change to a boring bar. Not impossible, I just need to draw it out.
 
LVLAaron said:
Yeah... after I typed my last message, I realized it gets tricky with a tool change to a boring bar. Not impossible, I just need to draw it out.
Click to expand...

If you can use same tool, then no tool change involved. If you use a V-style tool, you could do both. I use a CCGT for tenon and switch to the boring bar to cut a taper.
 
I can carefully touch off on the shoulder and tenon with the boring bar. There's a couple thou of give and take on the cone. I'm comfortable that I can hit it. Or I could do the whole thing with the boring bar.
 
Just remember to mark exactly where your compound is on zero before your start moving it. Once you start cranking it in and out, you need to get back to 0 for it to match your X&Y coordinates where you started. Again, I set mine mid-travel for a cone and zero the dial, then make a match mark across the base, so when your back to zero, you can see match marks line up. Or you could be off 1 revolution 1 way or the other. Hard to tell.
 
All of this pontificating... it's probably fine to do the tenon, chamber it, and cut the cone to the bottom of the extractor groove. You can put a panda barrel on a border with a spacer. I believe the only difference is the headspace.
 
LVLAaron said:
All of this pontificating... it's probably fine to do the tenon, chamber it, and cut the cone to the bottom of the extractor groove. You can put a panda barrel on a border with a spacer. I believe the only difference is the headspace.
Click to expand...

Yes, a hardened .215" spacer allows a 1.115" HS Stolle Panda barrel on a .9" HS Borden action.
 
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