short COAL

[MTBMaine]

Hi all, I recently rebarreled my savage 12 with a shilen .308. When trying to find distance to the lands using a hornady overall length gauge I am getting some very short COALs. With a 168smk I'm looking at a COAL of 2.7, that's with a .025 jump. Does this sound abnormal to anyone else?

Thanks

 

[TylerErickson]

Depends on a couple things, Sierra's book says for that bullet 2.800" is the COAL, how are you measuring your length, from base to ogive, or base to tip of bullet?

 

[jo191145]

Sounds quite short to me.

Are you sure your case gauge is releasing the bullet smoothly and straight. Sometimes a tight fit on the neck of an unconcentric gauge can force the bullet to exit sideways just enough to jam in the throat. No lie it happened to me.

Hold rifle with muzzle facing floor. Drop bullet down the chamber. Insert case gauge tool in chamber and lock rod as normal. If you still get a coal of 2.725 then that's it.

 

[MTBMaine]

Base to Ogive.

 

[jo191145]

COAL. Stands for cartridge overall length. Base to tip. 2.725 would be rather short for a 168 smk.

If 2.725 is your distance to lands using a comparator at its specific datum line that changes everything.

 

[MTBMaine]

Sounds quite short to me.

Are you sure your case gauge is releasing the bullet smoothly and straight. Sometimes a tight fit on the neck of an unconcentric gauge can force the bullet to exit sideways just enough to jam in the throat. No lie it happened to me.

Hold rifle with muzzle facing floor. Drop bullet down the chamber. Insert case gauge tool in chamber and lock rod as normal. If you still get a coal of 2.725 then that's it.

Thanks, Ill give this a try. Im going to talk to someone from Shilen also, maybe this barrel has a short throat for a reason?

 

[MTBMaine]

COAL. Stands for cartridge overall length. Base to tip. 2.725 would be rather short for a 168 smk.

If 2.725 is your distance to lands using a comparator at its specific datum line that changes everything.

I am measuring the distance from the base to the Ogive using a comparator

 

[jo191145]

Then your chamber is probably just fine. I'll assume your comparing your numbers using a comparator to numbers you see in reloading manuals. Reloading manuals use base to tip measurements.