Bullet Seating Depth

[sauced10]

How far do yall go back off the lands? Whats a good starting point. I've read people going from .010 - .200

I'm on the lands at 3.518" on a 300 WM.

[Dennis]

All depends! Some bullet like being jammed in the lands, some way off the lands.

Consult your manual, get a good start on your powder.

Once I have a good group, I start playing with seating depth.

I just finished tuning one today and it likes them .030 off the lands! I have a couple of guns that like them .020 in the lands!

Just remember, the closer you get to the lands, the chamber pressure rises with the same powder load!

What bullet's do you plan on shooting?

[sauced10]

All depends! Some bullet like being jammed in the lands, some way off the lands.

Consult your manual, get a good start on your powder.

Once I have a good group, I start playing with seating depth.

I just finished tuning one today and it likes them .030 off the lands! I have a couple of guns that like them .020 in the lands!

Just remember, the closer you get to the lands, the chamber pressure rises with the same powder load!

What bullet's do you plan on shooting?


I have a ton of core lokt's, nosler partitions and speer grand slams.

[gotcha]

Hi sauced ! Your cartridge length will be dictated by your magazine length unless you plan on shooting only one at a time. Chk. the length of the magazine 1st & leave a tenth inch short to insure reliable feeding. Note from Hornady manual: " When using cases of this size, it is imperative that the reloader work w/ near max. loads. Reduced loads w/ slow burning powder can produce dangerous hangfires, large muzzle flashes and perhaps dangerously high pressure". You didn't indicate bullet weights you'll be using. Hornady recommends RL-22 for bullets of 150/155 grs. & both RL-22 & IMR7828 for 165 gr. & up. Lighter bullets (under 150 grn.) like IMR-4350. I don't load belted cases so hopefully someone that does can chime in & give better detail for this cartridge. :) How's the new r/l equip. treating you ?

[sauced10]

Magazine is fine with .030 off the lands. 180gr

[450rydr]

I typically start off .010 off, but thats my personal preference. I've never had to seat bullets deeper to gain accuracy, just closer.(to the lands)

[wrvet05]

the hornady manual also says that the closer you are to the lands the more accurate your gun should typically be because of how fast the bullet will stabilize in the barrell.

[DanSavage]

I read an article before and it only made sense to me, it said when developing loads start at the lands so when you work up and find a good powder charge there is only one way to go with the seating, in and you won't have to worry about pressure spiking.

[bowhunter42]

mine is set to143 off the lands and it shoots great