Minimum seating depth for bullet neck tension??

[Colin78]

I got some 140 Elite Hunters for my creedmoor but when touching lands only .376" of the bullet is in the case neck and approximately.200 of that is boat tail. I'd like to start off .010 off the lands so that would give me .386" of total bullet in the case back but with .200 of that being boat tail that only gives me .186" of the neck gripping the bullet. I'm sure that's not enough right? What is the proper minimum length of bullet grip!

 

[ar10ar15man]

it will never work in a creedmore.
it is plenty i have use as little as .180 on a 308

 

[Colin78]

it will never work in a creedmore.
it is plenty i have use as little as .180 on a 308

I'm confused.... it will work or it won't?

 

[243winxb]

The bullets bearing surface thats in contact with the neck is 1 factor.

Neck tension is another.

Then action type, bolt or auto matters.

No easy answer.

Chamber and extract a few rounds. Measure OAL, has it changed?

Has the bullet become crooked in the neck from hitting a feed ramp?

My 223 minimum. .170" https://www.thehighroad.org/index.p...m-bullet-shank-in-contact-with-neck.1429/full

 

[ar10ar15man]

it should work just fine.
as suggested make a couple of dummies, cycle them and check for length change bent.
( i was joking that it would not work because it was a "creedmore")

seating depth is not a fixed number. oal of the bullet, caliber.

I'm confused.... it will work or it won't?

 

[DUSTY NOGGIN]

the rule of thumb that i have heard is bullet diameter deep , not including boat tail

but i dont know whos thumb it was , or if he/she even still has one ??

i think that rule came from a hunter , who planned on handling em loose in his pocket

since you are likely to be putting em in one at a time anyways while shooting paper/steel/target at a bench ... you will be fine cause your only moving em from the box to the action then back to the box ...

you just gotta know you are deciding to give up bullet support that you would have, if you set them deeper ...

maybe starting at the short seat, working longer something might shoot awesome with a little jump and be able to keep more support at the neck?

 

[Colin78]

Thanks for the replys. This is a hunting rifle and surprisingly they do fit in the magazine. I will seat a few and see how well they hold and make sure they can't be easily knocked out of place.

 

[dok7mm]

That's not much for a hunting round and if you have to chase the lands, it will only get worse over time.

I've got the same problem with eroded lands and vlds. I'm approaching it a couple of ways. I just loaded up a Berger test, to see if I can find accuracy with more jump and more bearing surface in the neck. The other option is to use a bullet with a shorter ogive length, like a tangent or hybrid bullet. Or a heavier pill with longer bearing surface & shorter ogive.

 

[Colin78]

That's not much for a hunting round and if you have to chase the lands, it will only get worse over time.

I've got the same problem with eroded lands and vlds. I'm approaching it a couple of ways. I just loaded up a Berger test, to see if I can find accuracy with more jump and more bearing surface in the neck. The other option is to use a bullet with a shorter ogive length, like a secant or hybrid bullet. Or a heavier pill with longer bearing surface & shorter ogive.

I agree, and I don't want to risk having a bullet get crooked or loose or something on a hunt where there could be a once in a lifetime shot opportunity blown due to this. I'm going to seat them deeper with a long jump and see what happens.

 

[misterc01]

I have found a variety of "rules" on this, many saying the minimum is the diameter of the projectile, others saying no less than 1/2 the diameter of the projectile. In practice, it should be in far enough that the bullet is straight, that is, properly aligned with the case - not tilted or misaligned which means bearing surface - not on the boat tail, and that there is proper neck tension. Neck tension is another viable with different thoughts on what is "correct." From what I have read and put into practice - .003″ less than the loaded outside diameter with bullet in place give excellent accuracy, and is a good starting point as you "tune" your particular firearm.

 

[Greyfox]

You should OK, but it's quite possible you can find a solid performance node seating .050-.100" off the lands. I have found this to be the case with several of the 6.5 Berger designs, including the VLD's. I'm going on 8 years of consistent performance with +1000 shots in my 6.5x284 using .075" OL with 140 VLD's. At the time of initial testing this was my optimum seating depth, and still is, with no throat erosion so far. Hunting cartridges tend to get a lot of handling and cycling making them more prone to getting knocked out of alignment if there is too little contact area in the neck. IMO.

 

[adam32]

the rule of thumb that i have heard is bullet diameter deep , not including boat tail

but i dont know whos thumb it was , or if he/she even still has one ??

That's the unofficial "rule of thumb" for neck length when creating a cartridge...I'm not sure if there's a rule of thumb for how much bullet needs to be in the neck...

 

[dougduey]

the rule of thumb that i have heard is bullet diameter deep , not including boat tail

This rule of thumb is correct. I've read it many times in different manuals.
Now, if you want to make very concentric ammo, you need to seat the bullet deep enough where the base of the bullet (flat base like a Partition) or the junction of the boat tail/bullet body (any boat tail bullet) is seated to the junction of the neck/shoulder of the brass case. I used to do all sorts of bullet seating depth tests, then I read about what I stated above. Rechecked the seating depth on my pet loads and found that they were all about this exact seating depth.

 

[misterc01]

Some find their sweeet spot with the bullet (ogive) seated in and on the lands.