Bulleting Depth and amount of bullet that must be seated in the case neck

[ehkempf]

I have a question about bullet seating depth, seating out into the lans when the chamber has a long throat. In other words if it is a long throat and in order to seat touching the lans, or into the lans, very little of the bullet would be left in case neck. Is there a general rule as to amount of bullet that must be seated in the case neck? I would assume (hate using that word) that more tension would be required as less and less of the bullet is seated in the case neck.

Thanks,

Ed

 

[abintx]

Bullet seating depth and neck tension are part of the fine tuning process once your load has been developed. Your barrel will tell you what it likes. The target will record its preference. There is no general rule. Each barrel is different. When any of the components used for reloading change, including powder lot, the whole process begins again including seating depth and neck tension adjustments. A full length die with a bushing cavity aides in the development of the most accurate load. Acquire a variety of bushing for assistance. Try different seating depths in .003" to .005" increments initially. Fine tune with .001" to .002" later. Tension changes are usually applied in .001" increments. Sometimes in .0005". But that's rare. Bullet type, bullet ogive and pressure ring, throat angle and freebore also make up part of the equation.

 

[Wilbur]

I had a rail gun barrel that won everything in sight. I could push sideways on a loaded bullet and it would pop out. Might be the exception but it proved to me that it didn't matter much about depth into the case. If you glued a boat tail into the mouth of a case you wouldn't have to turn case necks or worry about tension.

 

[ehkempf]

Bullet seating depth and neck tension are part of the fine tuning process once your load has been developed. Your barrel will tell you what it likes. The target will record its preference. There is no general rule. Each barrel is different. When any of the components used for reloading change, including powder lot, the whole process begins again including seating depth and neck tension adjustments. A full length die with a bushing cavity aides in the development of the most accurate load. Acquire a variety of bushing for assistance. Try different seating depths in .003" to .005" increments initially. Fine tune with .001" to .002" later. Tension changes are usually applied in .001" increments. Sometimes in .0005". But that's rare.

Thank you for the reply. You answer is good but it really did not answer my question, although my question might be poorly worded. My basic question is there a point of no return, so to speak, when you do not have enough of the bullet seated in the shell case. I have noticed that some times with a bullet touching the lans there is hardly any bullet being seated in the case. Is there a min. amount that must/should be seated?

I was writing this reply before I saw Wilbur's post. I guess that will answer my question.

Ed

 

[Charles E]

This question comes up a fair bit. Don't believe anyone's gone down to zero - no, that's wrong, I just don't know who's gone down to zero -- but when I reply to this kind of question, I point to the Wolf Pup, which has an .085 long neck.

Since that wins a lot, you can be pretty sure that .085 of neck engagement's OK...

 

[alinwa]

In testing this using 5 different reamers my opinion is that "it's nice to have the bullet seated to where the bullet doesn't fall out."

But it has no effect on accuracy.

That said, there's a whole slew of people, including the bulk of the competitive short range Bench Rest community, who believe strongly in "tuning with neck tension." If you ask 50 competitive BR shooters about VV133 49 of them will say "133 likes heavy neck tension."

You get to pick who you lissen to

(And please take the time to test this over time and record the results for future generations...)

anotheropinionby





al

 

[abintx]

Thank you for the reply. You answer is good but it really did not answer my question, although my question might be poorly worded. My basic question is there a point of no return, so to speak, when you do not have enough of the bullet seated in the shell case. I have noticed that some times with a bullet touching the lands there is hardly any bullet being seated in the case. Is there a min. amount that must/should be seated?

I guess you could say when the bullet won't stay seated no matter what you try. Using the proper amount of Freebore and throat angle with your bullet of choice in your next barrel should prevent ever having to worry about the situation you described above. It appears that you may have an excessive amount of Freebore; easily rectified by the right reamer.

"Normally it is quite short and the rifling starts perhaps only one 32nd of an inch from the bullet; but in some rifles the freebore might allow over half an inch of bullet travel before it contacts the rifling firmly" [Hornady Manufacturing quote]

If you're not familiar with Freebore [also known as Leade] and throat angles here's two good references: http://media.photobucket.com/image/picture of freebore/Tomate_08/freebore2.jpg and http://www.riflebarrels.com/articles/bullets_ballastics/throat_angles.htm

 

[virg]

Short answer to your question in my HO is; no. There is no rule of thumb answer. As long as the neck of the brass holds the bullet during normal handling and placement into the action, accuracy will not be affected. But, I'm sure there are thousands that will disagree.

virg

 

[Pete Wass]

My belief is there are two ways to tune: 1. Using an exact load and exact seating depth and 2. Jamming the bullet into the lands and finding the powder charge that makes a tiny round hole.

It is my Personal beleif that a loaded round with a consistent amount of bullet into the lands and an exact, weighed to the .00 on a Labratory Balance ( an electronic scale of good quality that will read, RELIABLY to .00), will give one the best possible chance at Winning. To go at it any other way , while successful for many, is chancy, at best, IMHO. Just imagine how well the best shooters would shoot with perfect ammo . OR how much better some folks who struggle, at times might do - - - -

It is also my belief and I endeavor to have as little of the bullet into the lands as possible. Why? Well, if I want or need to open my bolt, the bullet will remain in the case. Oh,we must have enough neck tension to be able to hold the bullet in the case to get it back out of the lands. It has been my experience that by using .004" of neck tension, I can pull bullets from the lands with .010" of " jam" from where one can just faintly see land marks on a bullet, More and the bullet is likely to remain and powder is likely to be dumped in the event of a bad primer or the Range Officer sez," Open your bolts; Remove your bolts"!

I am thinking the only thing tuning with neck tension is doing is increasing pressure. Why not walk around that and simply use the powder charge? With light land engagement, one variable is removed.