I've just loaded a few of different batches of .308win for load development...

Using a digital caliper and a Stoney Point comparaor to measure the COL to the ogive, I am getting a consistency of .001" on some batches and 0.0005" on others. Is this good, bad or indifferent?

When I come to vary the COL to fine tune a load,
in what increments should I vary the COL ie .01 or .05" or what???

Thanks in advance,

Pete

Pete

Measuring to the ogive and COL are two different things, as you know. Only the first is important to accuracy.

If you are getting 1/2 to 1 thou variation you have some damn fine ammunition.

Start with the bullet seated into the lands. That way you have only one direction to go to fine tune. Start with .010 increments. When you've narrowed it down you can fine tune to .005. Don't be surprised if the sweet spot is right back where you started, i.e., touching the lands.

Ray

quote:

Originally posted by Pete E:
I've just loaded a few of different batches of .308win for load development...

Using a digital caliper and a Stoney Point comparaor to measure the COL to the ogive, I am getting a consistency of .001" on some batches and 0.0005" on others. Is this good, bad or indifferent?

When I come to vary the COL to fine tune a load,
in what increments should I vary the COL ie .01 or .05" or what???

Thanks in advance,

Pete

It sounds like your measurements are fine.

I work in 0.010" increments when adjusting the COL and when I find a lenght that seems to be what the rifle likes I try 0.005" on both sides of it to see if there is any improvement.

Warning Pete...don't stuff any mono-metal bullet up against the rifling first thing in your load development. Back off .050" and adjust in or out as needed. Barnes, Nosler and GS copper bullets need to jump into the rifling on firing.

Ol' Joe and Cheechako's advise is good for cup-and-leadcore type bullets only. And it is good advise.

Thanks Gents..

I'm taking my reloading a little bit more seriously these days and without getting into anything like neck turning, I'm trying to get my ammo as consistent as possible...Next it will be run out, something I know absolutely nothing about!

Regards,

Pete