COL tollerances- what's yours?

castnblast · September 22, 2007, 04:38 PM

Just curious...due to variations in ogive, and soft points, for your HUNTING rounds, what do you accept as an acceptable tollerance in COL variations? I've been using a .003+or-. These rounds are not being loaded to the lands and grooves. They are pretty close to factory specs...in particular, 22-250. I'm using 2.350 as my median.

kirbymagnum · September 22, 2007, 07:22 PM

I keep my hunting rounds with in 0.002" + or - of eachother.

Linear Thinker · September 22, 2007, 08:53 PM

It depends. Minute-of-moose accuracy requirement is not the same as minute-of-prairie-dog.
I always seat on the ogive, my COL with soft-pointed bullets is +- 0.010. With plastic tipped Nosler and Hornady 22 and 6mm bullets, the COL is within .003.
LT

30Cal · September 24, 2007, 02:04 PM

I don't worry about it. The ogive is what counts, not the tip. The seating die should seat from the ogive. Tips vary on the bullet from one to the next, so if you make all the tips the same, then the ogives (what counts) will be all over the place.

Ty

rwilson452 · September 24, 2007, 03:07 PM

I would suggest you start seating them out further I would suggest you seat them out in 0.005 steps you should see a pont of maximum accuracy. Don't seat all the way into the lands. Generally you will find that somewhere between .015 and .030 off the lands works best. with some rifles the throat is so deep you can't do this. you want to leave about .224 of bullet in the case at least. I can't resolve this any closer for you as every rifle is different. Once you get the best C.O.A.L you might want to tweek your powder charge again.

firechicken · September 24, 2007, 05:55 PM

I use a Stoney Point comparator to find the seating depth of my precision rifle loads. It measures the bullets from the ogive instead of on the tip. I've found that when I use quality bullets....or at least medium quality bullets......that the variance is 0.000". That's using the Lee "dead length" seater die.

castnblast · September 28, 2007, 02:40 PM

Thanks. I'm going to look into one of those. How do they work? (Stoney point comparator)

September 22, 2007, 04:38 PM	#1
castnblast Senior Member Join Date: July 2, 2006 Location: Corpus Christi TX Posts: 1,148	COL tollerances- what's yours? Just curious...due to variations in ogive, and soft points, for your HUNTING rounds, what do you accept as an acceptable tollerance in COL variations? I've been using a .003+or-. These rounds are not being loaded to the lands and grooves. They are pretty close to factory specs...in particular, 22-250. I'm using 2.350 as my median. __________________ VEGETARIAN...old indian word for bad hunter

September 24, 2007, 05:55 PM	#6
firechicken Senior Member Join Date: April 17, 2006 Location: Savannah, MO Posts: 224	I use a Stoney Point comparator to find the seating depth of my precision rifle loads. It measures the bullets from the ogive instead of on the tip. I've found that when I use quality bullets....or at least medium quality bullets......that the variance is 0.000". That's using the Lee "dead length" seater die. __________________ The only thing necessary for the triumph of evil is for good men to do nothing. - Edmund Burke

September 28, 2007, 02:40 PM	#7
castnblast Senior Member Join Date: July 2, 2006 Location: Corpus Christi TX Posts: 1,148	Thanks. I'm going to look into one of those. How do they work? (Stoney point comparator) __________________ VEGETARIAN...old indian word for bad hunter

September 22, 2007, 07:22 PM	#2
kirbymagnum Senior Member Join Date: October 15, 2005 Location: Alberta Posts: 410	I keep my hunting rounds with in 0.002" + or - of eachother.

September 22, 2007, 08:53 PM	#3
Linear Thinker Senior Member Join Date: February 10, 2007 Location: Blue State, NE US Posts: 202	It depends. Minute-of-moose accuracy requirement is not the same as minute-of-prairie-dog. I always seat on the ogive, my COL with soft-pointed bullets is +- 0.010. With plastic tipped Nosler and Hornady 22 and 6mm bullets, the COL is within .003. LT

September 24, 2007, 02:04 PM	#4
30Cal Senior Member Join Date: December 3, 2002 Posts: 1,264	I don't worry about it. The ogive is what counts, not the tip. The seating die should seat from the ogive. Tips vary on the bullet from one to the next, so if you make all the tips the same, then the ogives (what counts) will be all over the place. Ty

September 24, 2007, 03:07 PM	#5
rwilson452 Senior Member Join Date: June 10, 2004 Location: Tioga co. PA Posts: 2,647	I would suggest you start seating them out further I would suggest you seat them out in 0.005 steps you should see a pont of maximum accuracy. Don't seat all the way into the lands. Generally you will find that somewhere between .015 and .030 off the lands works best. with some rifles the throat is so deep you can't do this. you want to leave about .224 of bullet in the case at least. I can't resolve this any closer for you as every rifle is different. Once you get the best C.O.A.L you might want to tweek your powder charge again.