how far can you fill a rifle cartridge?

[skyjerk]

This is a newb question.

I'm reloading .308 Winchester using 150 gr FMJ and Hodgdon Varget.
Following their (website) formula, I can start with 44 grains to a max of 47 grains,
so I made 10 each at 44, 45, 46, and 47 grains, to test them out for accuracy.

Well 47 grains fills the case right up into the neck.

The 47 grain formula says "47.0C" and I'm assuming that the "C" means
capacity, as in thats all you can fit in there, although the page does not explain the "C" I can see no other meaning it could have.

The bullet seats fine with no problems so my "gut" says this should be OK.

Just wanting a little confirmation that loading this full should pose no problems...

[Dave in PA]

'C' means compressed, as in the bullet will compress the powder charge when inserted......

[skyjerk]

'C' means compressed, as in the bullet will compress the powder charge when inserted......

Does compressing the powder generally affect accuracy adversely? I must have some effect on the burn rate I'm thinking,
although I dont know enough to guess if that would have a positive effect, a negative effect, or no effect at all.

[Lycanthrope]

A full cartridge of powder can help burn rate. If the cartridge is half full of powder, sometimes the powder settles toward the rear near the primer, when other times it may be forward. Not that either is really bad (I find powder toward the primer helps increase pressure and speed in pistol loads), but you need consistency for accuracy. A lot of this will vary with powder type as well.

I never tooled around much with compressed loads, but it's a valid load with Varget.

[skyjerk]

UPDATE

Well damned if that compressed load wasn't the most accurate of the 4 loads I tested

I shot 10 rounds at 100 yards with real gusty variable winds and 8 of them
were around .75 inch with 2 flyers which I attribute to strong gusts.

I bet that group is closer to .6 with no wind. Cant wait to try again...

Just FYI, this is fired from a brand new DPMS LR-308 with a standard
production 20" heavy barrel. Less than 100 rounds through this rife so far...

[Xringshooter]

Sounds like you found a load that your rifle likes to eat. That's the fun of reloading, when you find that one load that is a tack driver.