How far off the lands do you start?

bnewt3

Lil-Rokslider
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Nov 5, 2023
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Im assuming once you work with a rifle/barrel a bit you learn generally what it likes, but what is your default when developing a load on a new rifle/barrel?
 
.020 on this stw and 195's, will be around there when I swap to a 7PRC. Will look at some load data from guys I trust, pick a distance and leave it there.
 
Often the magazine dictates the maximum length. Many new rifles have shown up opening day and the magazine won’t feed because the cartridge length is too long, so make sure and cycle at least one full magazine before the season.

If the magazine doesn’t limit length, .020” is commonly picked because it’s close enough without usually causing issues. The danger of being too close, like just a few thou from touching, is slight differences in length might put some bullets into the lands and other not, which is never good.
 
Depending on what I'm loading for...I start at either .010 off the lands or max magazine length and work away from the lands.

For example, in a 25 Creed with 135s...I start .010 off the lands and see how it looks in the mags. If I need to seat deeper to fit in the mags...then that's my new starting point....then I go deeper if needed.

For things like a 22 Creed with 64 TGK...I just start .010 off because I'm not gonna be anywhere near mag length anyway.
 
I usually set them about 50-60 thou off the lands to start. Reason? This article came out a while back and it made sense to me. https://precisionrifleblog.com/2020/04/05/bullet-jump-load-development-data/ Along with others indicating things are less likely to get wonky as throat wear occurs if you've got a longer jump. I tend to start with bullets not known to be particularly finicky about jump and am happy to avoid bullet jump testing most of the time during load dev these days.

Obviously mag length and how much bearing surface is in the neck plays a part too. A tikka 6.5 creed chamber for example seems to need a longer jump if you want a 140 hybrid to have a decent bit of bearing surface in the neck or fit a mag.
 
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