Bullet jump vs mag coal.

[wapitibob]

I don't even have a mag box in my rifle, I load .020 off the lands and leave it.

 

[MT762]

Well folks, did it again today with some once fired united brass. I didn't have to force the bolt to close this time. New measurement is .02" for the 6.5 and .03" for the .308 above mag limit

Basically all cartridges are designed so that with the bullet seated at or around magazine length, it has to jump through space to the lands. Otherwise folks would be getting bullets stuck in the rifling every time they chambered and unchambered a round without firing.

.02-.03 jump to the lands from mag length is generally a good place to be. Lots of bullets won't shoot unless you are jumping them .05. And even finicky bullets will shoot well at a large range of jumps. For instance they might shoot well at .025-.035, but also at .075-.085, at .150-.160, etc. It's fairly rare that a bullet only shoots well at one exact jump.

 

[streamerfish]

Lol, isn't that all of reloading? If I didn't want to think then I'd just keep buying the same factory norma ammo that shoots really well for me.

I feel ya. I like to tinker as well.....but, IMHO, especially on the creedmoor, seating depth tinkering is largely futility.

Tinker with bullets, powders, cases etc. Real world differences to play around with.