Index barrel formula question

[Dave in WI]

Have a barreled action here that possibly has chamber cut a little long (primers back out a little on factory ammo.) Waiting for set of go/no-go gauges. Barrel is already engraved. If I were to set back shoulder, tenon and counter bore required amount, is there a quick formula to figure out the degrees barrel will rotate per .001" of removal? This is a Reminton 700 with 16 TPI.
I know brass can be fire-formed and reloaded to chamber.
TIA

 

[powderbrake]

1 rotation is .0625. (16 threads per inch)

.001/.0625 = .016 of a revolution

.016 X 360 degrees= 5.75 degrees per .001 removal.

 

[edwardware]

Well, 360 degrees of rotation will get you one thread pitch. . . that being the definition of thread pitch and all.

So 1 degree will get you 1/360th of the thread pitch.

primers back out a little on factory ammo.

I don't think I've ever measured a factory round that didn't leave headspace to spare.

Proud primers are more likely to be a symptom of low pressure in normal headspace than slightly excessive headspace. If pressure is nominal, the case will stretch back to the boltface and primer protrusion will be 0.000.

 

[gunsandgunsmithing]

1 rotation is .0625. (16 threads per inch)

.001/.0625 = .016 of a revolution

.016 X 360 degrees= 5.75 degrees per .001 removal.

Beat me to it but I'd wait on the hs gauges, as factory ammo or new brass typically runs a bit short.

 

[Dave in WI]

Thanks for the quick replies. Of course I will wait for gauges. Just over thinking and planning ahead.