Seating into the lands?

JDLawrence3

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Dec 25, 2021
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I am fairly new to reloading, at least for long range. I have experience with handgun, 223, and 450 BM loads, and stick to SAAMI specs with them. My simple question here, is this. Is it safe to seat the bullet so that it is in the lands when closing the bolt, as long as I do not see pressure signs? If so, how far is acceptable?

Here is how I got to this question, for anyone that wants/needs some backstory to answer my question.

I recently purchased a Savage Elite Precision in 338LM. After getting ahold of what I could get my hands on and doing a little research, I started a few initial loads. My first loads were with GWT brass, Remington 9 1/2 primers, LRT, and 300 gr. A tips. I started with charges of 97, 98, 99 gr. to see what grouped best. After sighting the rifle in at 100 yards, with some 285 ELDM handloads from a buddy (which were sub MOA once dialed in), I started with the 97 gr. rounds. These rounds grouped the best out of all of the charges (roughly .6 MOA at 100 yd.) and were pretty consistent going straight to 600 yd. I noticed that there was a little stiffness closing the bolt, but didnt think much of it, as it is a new rifle and I had not had a feel for it yet (my mistake). It wasnt until after shooting and wondering why the bolt was stiff, that I realized that the rounds were loaded to 3.861" instead of 3.681". I was loading one round at a time into the gun, therefore, I didnt know that the rounds did not fit in the mag. Once this mistake was recognized, I inspected all of my brass that I fired at that OAL for pressure signs. None. I went back and loaded rounds, with the only difference being the correct OAL. My groups went to shit (2.5 MOA at 100 yd.). I ordered the Hornady OAL tool and modified case for 338LM and measured my gun to see the distance to the lands. My measurement came out to 3.855". I loaded up rounds with 97 gr. at 3.845" and shot them yesterday. My group improved, but not by much. Is it safe to go back to 3.861" and see if my original success with the setup is repeatable?

I have heard that these A tips are very sensitive, and have proved to be so in my experience. I have shot 285 ELDMs and 300 SMKs at 3.681" and had MOA or better groups. Id like to think that it is not me throwing shots, only with A tips and not other projectiles. I understand that Lapua brass and different powder could help, but other projectiles dont seem to mind the GWT or the LRT. They are also what were available to me within reason, in today's market. Thanks for any help!
 

Doom

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Loading at or into the lands has one goal, accuracy. It also has drawbacks. It does raise pressure versus seating away for a given charge. Another issue is it’s hard to be consistent getting the same jam on each round.

On a bad day you may chamber a round then have to unload it unfired. That case extracts, the bullet stays in the rifle, and powder is ......

There is a whole series of articles on the Precision Rifle Blog that discuss seating depth. I would suggest a trip over there.
 

JDLawrence3

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Dec 25, 2021
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Lincoln, DE
Loading at or into the lands has one goal, accuracy. It also has drawbacks. It does raise pressure versus seating away for a given charge. Another issue is it’s hard to be consistent getting the same jam on each round.

On a bad day you may chamber a round then have to unload it unfired. That case extracts, the bullet stays in the rifle, and powder is ......

There is a whole series of articles on the Precision Rifle Blog that discuss seating depth. I would suggest a trip over there.
Thanks. Ill check out some of the articles when I get an opportunity.
 

MinnesotaMulisha

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    At some point, no matter how much jam you have, the lands will seat the bullet deeper into the case.

    I can’t begin to say how much as there are too many variables.

    I would load .020” off and start from there.
     

    spife7980

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    Jamming is perfectly fine so long as you dont have too much powder in the case. Obviously lol.

    I would work up powder with it jammed and then seat deeper to jump rather than jumping them for powder tests and then proceeding to jamming. You dont have to worry about it unless youre sorta close to your max already as you seem to have found out.

    I, too, would seat at .020 and then test in deeper seating depths rather than going back to jam.
     

    alamo5000

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    I am fairly new to reloading, at least for long range. I have experience with handgun, 223, and 450 BM loads, and stick to SAAMI specs with them. My simple question here, is this. Is it safe to seat the bullet so that it is in the lands when closing the bolt, as long as I do not see pressure signs? If so, how far is acceptable?
    When and where you seat into the lands matters.

    Let me give a non shooting related analogy. Imagine if you were some place and needed to drive over a curb in your pickup truck. If you slowly creep up to the curb and make sure both front tires are square and making even contact and then tried to drive over....

    vs

    You get back 10 or 15 feet and you get up a little head of steam before driving over the curb...

    Which one will work better, and how so?

    In the first example you will need a lot more engine power to accomplish the goal. It's not a perfect example but it demonstrates a point. That being when shooting/reloading the same principle applies. If you load way out into the lands the probability of high pressure spikes goes way up. The energy from the powder not only has to overcome the weight of the bullet and the friction of the barrel, it also has to overcome an additional initial barrier (just like with the truck up next to the curb). It can do it but the pressure will be a lot higher depending on the circumstances.

    It's pretty possible to have good or even great loads out in the lands (I guess), but I personally have never seen a need to do it.
     
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    Missalot

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    I don't like it because as Doom notes, there is the possibility the you will end up with a bullet jammed in the lands when you open the bolt on an unfired round. Then you will be looking for a way to tap the bullet out and will have to clean the chamber of powder before you can load the next round. A real pita if you are in the field.
     

    Haney

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    Jamming is perfectly fine so long as you dont have too much powder in the case. Obviously lol.

    I would work up powder with it jammed and then seat deeper to jump rather than jumping them for powder tests and then proceeding to jamming. You dont have to worry about it unless youre sorta close to your max already as you seem to have found out.

    I, too, would seat at .020 and then test in deeper seating depths rather than going back to jam.
    Are you talking jamming or soft-seating ? Jamming does not push the bullet into the case ,soft-seating does .
     

    Haney

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    And no where in my comment did I address or even allude to anything of the sort. So quit trying to read into stuff just enough to pick fights you dumb ass.
    Maybe where you mention the amount of powder in the case ? dumbass JAMMING does not reduce case capacity. Nice try though .
     

    spife7980

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    Maybe where you mention the amount of powder in the case ? dumbass JAMMING does not reduce case capacity. Nice try though .
    No, but if you have enough powder in the case up towards the maximum then the additional increase in pressure cased by starting jammed might be too much to handle.

    So no where and I discussing the jamming seating the bullet deeper nor its impact on case capacity.
    Again, quit picking fights with you smooth brained insights and stay on the short bus.