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How deep is too deep?

Seating depth, how deep is too deep? I have a 260 rem and with a 140 VLD the base of the bullet is .060" below the body shoulder junction when it touches the lands. Not the neck shoulder junction but body and shoulder junction. Is that going to effect preformance?
 
The deeper the bullet sits, the less the case volume, the less powder you can put in, and the more pressure you will get for the same powder load.
 
One of the issues you have to work with when choosing that bullet for that gun. With the VLD that deep, you will have pressures build faster in the case than a non-VLD bullet of the same weight. When the bullet is seated in the neck, all of the pressure is building "behind" the bullet. The bullet starts to move before the pressure reaches max. When the bullet is seated deep, the pressure is building "around" the bullet. Since pressure is not pushing solely from behind, it takes a little longer before the bullet starts to move. A little longer equals higher pressure and brass expansion before the bullet starts to move. I hoped you backed off the powder charge and are working up. If you really like that bullet, you may see if someone has a throating reamer and open up the throat a little in your gun. Seat the bullet out a little more and you will gain some velocity and not reach the max pressure near as fast.
 
Bullet heels having to be exactly at, or any other dimension from the case neck-shoulder juncture is myth number 8361 in all that exist in the reloading world.

Most bullet's heels are larger in diameter than their body is forward of that anyway. Easily seen with proper use of a mic with .0001" scale their thimble turns against. Could that be called the bullet's donut?
 
Im running new brass so no donut yet.
New brass includes donut inherent to manufacture. That is, brass thickness tapers from webs all the way to mouths.
Do you FL size necks, or partial length size them?

Personally, I would put together a better plan than yours.
 
New brass includes donut inherent to manufacture.
Military bottleneck brass is that way as is most commercial brass. I've pulled bullets from 30 caliber match ammo, cleaned the black sealant out then dropped cleaned bullets in their necks. Neck outside diameters the same before and after; no change in inside neck diameter. Bullets are smaller in diameter than case necks (throats?) by about .001" or more. That donut at the shoulder stops bullets from falling into the case body; it's diameter is smaller than bullets.
 
The deeper the bullet sits, the less the case volume, the less powder you can put in, and the more pressure you will get for the same powder load.
Not always. Tests have shown as bullets starting out against the lands then incrementally seated deeper in case necks, pressure drops for a ways then starts back up. Somewhere mid point in bullet seating depths is where pressure is lowest. The range peak pressure has varies with bullet extraction (pull) force, throat dimensions and bullet hardness as well as powder burn rates.
 
Im fl resizing. And what plan are you talking about? This is not the only bullet i plan to try. I also am going to try 130 hybrids. Im not sure why i would get a donut im not neck turning at all.
 
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There's more spring back of the neck at the shoulder when fired; more metal from the shoulder springing back. Happens with all necks; turned/uniformed or not. Microscopic sometimes, but still there.

200 and 210 grain bullets go past that donut in my 303 Win cases. They shoot as accurate as lighter ones whose heel stops before going past the donut.
 
Wouldnt the expander ball on a fl push it to the outside? If this is going to happen what tools do i need to remove it? Inside forster neck reamer? Or neck turner?
 
There's more spring back of the neck at the shoulder when fired; more metal from the shoulder springing back. Happens with all necks; turned/uniformed or not. Microscopic sometimes, but still there.
Besides the neck walls being thicker at the neck/shoulder junction than at the case mouth, I like to think of the shoulder as a buttress. When the neck expands at the shoulder junction, there's a force vector trying to compress the shoulder walls towards the shoulder/body junction, but naturally there's stiff resistance, so the spring-back at the neck/shoulder junction is more pronounced than elsewhere on the neck.
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Wouldnt the expander ball on a fl push it to the outside?
Yes. Then it'll spring back after the expander ball's left that point. Exactly like the entire length of the case neck and body outside dimensions. They all spring back from some dimension they're sized to. Brass is nothing but very hard rubber; it has elasticity just like all metals.

my 30 caliber case necks squeeze down to .331" diameter in the die's neck that size. After the case is out of the die, it's neck is about .332" diameter. They spring back from expander ball diameters, too.

Measure your sizing die's neck diameter and case necks coming out of it. Take the expander ball out first on some, leave it in for others. Measure everything before and after.
 

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