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Posted By: TheBig1 Seating Depth Question - 07/31/16
I'm a new reloader so please bare with me and enlighten me.

The lands on my rifle are at 2.210 ogive and to sit back off of them I like 2.116 ogive.

My question is, with sshorter bullets it doesn't sit very deep in the case. How much of the back of the bullet should be in the case? Or is it not practical to be able to seat at that length all of the time?

Posted By: NVhntr Re: Seating Depth Question - 07/31/16
Good practice is to match caliber with seating depth as a minimum.
IE: a .223 bullet would have the bearing surface seated at least .223" (boat tail doesn't count).

I have gone a bit less at times reaching for the lands with target bullets.

I wouldn't go less with hunting bullets.
Posted By: TheBig1 Re: Seating Depth Question - 07/31/16
Thanks NV. I'm reloading for a 22-250. 55gr Hornady FMJ'S were getting a little short on the back so I jumped to a 60gr Sierra HP for more length.

Now that I'd like to try other bullets, I need to know where that middle ground of trying to reach the lands and keeping enough bullet seated in the case is.
Posted By: mathman Re: Seating Depth Question - 08/03/16
Originally Posted by NVhntr
Good practice is to match caliber with seating depth as a minimum.
IE: a .223 bullet would have the bearing surface seated at least .223" (boat tail doesn't count).

I have gone a bit less at times reaching for the lands with target bullets.

I wouldn't go less with hunting bullets.


There are a whole lot of 300 Win. mag and 300 Savage rifles out there that dispute the necessity of said good practice.
Posted By: Tejano Re: Seating Depth Question - 08/05/16
They can be a good bit shorter than caliber length. I have some loads that only use a third of the neck. I test them by pushing the bullet against a piece of scrap wood pretty hard and if they don't move I'll leave one in the magazine for 10-20 shots then again check for any movement.

If they do get shorter I will try more neck tension and repeat the exercise.

The one caliber or more neck length is a good standard for case design but not a hard and fast rule for seating bullets.

The main requirements for bullet seating are that it is straight and it doesn't shift.
Posted By: TheBig1 Re: Seating Depth Question - 08/05/16
Thanks Tejano, I appreciate that.
Posted By: 1minute Re: Seating Depth Question - 08/05/16
On another tangent-With Weatherby's and free bore it's near impossible to reach the lands. Still I played a lot with seating depth to the extreme that I placed each round in the chamber with only about 0.1" of neck holding the slug. Running them through the magazine and action would have induced runout. Groups tightened up when I had things shoved in to about the caliber distance. Pretty much using all of the neck to grasp ones slug. My suspicion is that a good consistent grip by the neck helped stabilize ignition pressures and thereby accuracy.

Without free bore, I'm nudged up pretty close, but I don't use light for caliber slugs.
Posted By: NVhntr Re: Seating Depth Question - 08/05/16
Originally Posted by Tejano
They can be a good bit shorter than caliber length. I have some loads that only use a third of the neck. I test them by pushing the bullet against a piece of scrap wood pretty hard and if they don't move I'll leave one in the magazine for 10-20 shots then again check for any movement.

If they do get shorter I will try more neck tension and repeat the exercise.

The one caliber or more neck length is a good standard for case design but not a hard and fast rule for seating bullets.

The main requirements for bullet seating are that it is straight and it doesn't shift.


Hence the term, "good practice". How's the runout using 1/3 of the neck?
Posted By: 1minute Re: Seating Depth Question - 08/06/16
In my Weatherby efforts just cycling a cartridge with shallow seating through the action could induce bullet run out.
Posted By: Tejano Re: Seating Depth Question - 08/09/16
Even with the shallow seating the run out was acceptable at least according to the wobble test. Rolling the cartridges across glass.

Like 1 minute if the cartridges were dry cycled or banged around in my pack more run out could occur but not enough to hurt mid range hunting loads. If I can get close to the same accuracy by seating deeper I do. I stop at about .003 neck tension as well as other things happen with tighter necks like bending the neck or buckling the shoulder slightly.

My accuracy standards are not that high for hunting loads. Once I get consistent groups of around an inch or less I usually stop load work and go hunting. On a really accurate rifle I will tweak around trying to get half inch or less groups but don't worry if it doesn't get there.
Posted By: TheBig1 Re: Seating Depth Question - 08/09/16
Thanks Tejano.

One question that I do have and don't understand as of yet is about "Neck Tension".

Can this be explained a little?

I really only know a little bit about nothing as far as it pertains to reloading.
Posted By: Oldman03 Re: Seating Depth Question - 08/14/16
In short, neck tension is how tight the bullet is held in the neck of the case. Too loose and the bullet could move or fall out during normal operations. Too tight and it will effect accuracy and possible cause case problems.

When neck sizing or FL resizing, the die reshapes the neck, usually but not always, stretching it, thus the need to trim the case.

Here is an article that will explain it better than I can.

http://www.accurateshooter.com/technical-articles/reloading/neck-tension-not-just-bushing-size/
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