cutting a barrel for a coned bolt?

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Robmcleod82

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What way would you guys recommend for chambering a barrel that is going on an action with a coned bolt? (pierce single shot with 30 degree coned bolt)i was figuring I would leave the tenon long and start cutting the cone.
 
Close measurements first... then a bit of trail and error... I prefer to end up with about 5 thou clearance between barrel and bolt when the barrel is tight.
 
Use a feeler gauge between the receiver ring and lug to figure how much more you need to cut from the shank. Feeler gauge thickness + your desired clearance. As your compound will be offset 30* use a dial indicator on the carriage to set the depth of your cut.
 
Always check the angle. It's one of those things you need to creep up on, very hard to measure afterwards. If it's a Pierce why don't you ask them if they have a method they suggest? Kelbly has one on their site. I normally do it the same as PJS.
 
At that point it's too late. Use a protractor to measure the bolt and to set the compound, don't assume 30 on the bolt will match 30 on the lathe. Make a cut to get started then screw on the action with the bolt closed and measure the distance between the face of the action and the barrel. Do this a few times as you sneek up on it and make your last cut by adding .005" or whatever you want for clearance.
 
Ian Robertson said:
At that point it's too late. Use a protractor to measure the bolt and to set the compound, don't assume 30 on the bolt will match 30 on the lathe. Make a cut to get started then screw on the action with the bolt closed and measure the distance between the face of the action and the barrel. Do this a few times as you sneek up on it and make your last cut by adding .005" or whatever you want for clearance.
Click to expand...

This is what I do too...
 
As I sneak up on it I "measure" how much clearance I have by screwing the action on the bbl and insert the bolt while still in the lathe. Put a dial indicator on the bolt (stripped of cocking piece) then move the closed bolt back and forth in the action and measure the distance between when the bolt is touching locking lugs and hitting bbl face. Be sure the bolt handle is not hitting the receiver and you are actually moving the bolt forwards until it hits the bbl face. Just like head space will loose a bit of clearance due to crush when the bbl is actually tightened.
 
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