Neck sizing is bad. (Easy to find thread)
Why if you don't bump the shoulder back and the cases are fire formed to the chamber is it not consistent? It should be the most consistent and that's one of two arguments I've heard for 38 years of handloading that is the big plus for neck sizing. You don't work the brass as much and it gives a consistent powder capacity.
I totally understand mitdr774’s reluctance to get into such a discussion; he works hard, he’s tired and he won’t change his mind under any circumstances. I get that.
On the other hand Snake, you and I can talk and argue like nobody’s business and have fun doing it. So here goes.
You’ve been told wrong and you have been doing it wrong for 38 years and N/S can actually damage your rifles. How is that for an opening salvo? (Pegasus must be nuttier than usual.)
Now you know me, I always back up my statements with data and explanations, so here goes.
Your two arguments for N/S don’t stand up when you examine them critically. Let’s take the first one: “you don’t work the brass as much.” By that you are saying that N/S does not work the brass as much as F/L sizing. Please tell me in which universe you have EVER seen brass that was overworked by F/L sizing and how could you even tell that was the case? How do you know the brass has been “overworked?”
In my few weeks of handoading, I have never seen a case that was “overworked by F/L sizing.” I have seen case head separation, I have seen neck splits, I have seen failing shoulders, and most of all, I have seen primer pockets that are so enlarged the primers don’t stay in. I have yet to see a case fail because of F/L sizing overwork.
Case head separation is caused by someone not knowing how to set their sizing die and it can be discovered by using the technique described in the other thread. But if you set your sizing die properly, it will never happen and I don’t even bother checking that.
Split necks are caused by the use of standard sizing dies (N/S or F/L) where the mouth of the case is closed more than it should be and then expanded again by the expander ball. This occurs more often from rifles with a generous leade where the case mouth expands more than usual. When you work that case mouth with a standard die over and over again, it will split. You can alleviate that with annealing but even more specifically by eschewing the use of standard dies and using a bushing die with the proper size bushing and placing the expander ball in low Earth orbit where it belongs.
Failing shoulders is very rare and I have seen that with certain specific ancient calibers and with people using body dies. (Hold that thought, we’ll come back to it.) When you resize the case or more commonly when you use the body die, the shoulders do not go back properly and they crumple. This is very rare, but I have seen it.
The most common cause of death for a rifle case is the loose primer pocket. This will occur when you foolishly insist on using very stout loads in your rifle. That’s what kills my brass, because I do use very stout loads. I believe I **** the primer pocket expansion by using a small base F/L die from the first sizing as it pushes the case head back together some after each firing. I get 8 loadings with my brass from virgin and then I retire it. By that time the primer is VERY easy to insert.
Overworking my brass due to sizing? I don’t even know what that would look like. Do you?
Now that we have shot that first canard down, let’s go after the second one; brace yourself, it’s going to be rough.
When you neck size, the only thing you are doing is pushing back the neck to a smaller dimension, the body and shoulder of the case are untouched.
Now, when you fire a cartridge for the first time in your action, the principle of operation is for the case to expand until it is stopped by the chamber and it can’t expand any further. The mouth of the case expands also to obturate the bore and prevent the hot gases from going back into the chamber and your face. Everything goes out the barrel. When the pressure drops, the case shrinks back, a little, and comes off the wall. The bolt rotates the case to break any remaining stickiness and then pulls the fired case out of the chamber.
Brass has some elasticity inherent to it. This is why the case does shrink back a bit so you can pull it out. However that elasticity can be overcome with too much pressure. This is what happens when a bolt is hard to open. The brass was overworked due to too high a pressure and will not shrink back. When you try to rotate the bolt, the case is stuck to the wall of the chamber and it will not let go easily.
With me so far?
Ok. Now when you neck size, you do not bring back the case to a starting volume. The case now has the volume of a fired case that has shrunk back a bit. The next time you fire it the case expands again and shrinks back, but less than the prior time. Your twice-fired case now has an internal volume that is even greater than after the first firing. At some point, the N/S case becomes too difficult to rotate and extract. Neck sizers pull out something called a body die (told you we would come back to it) or may even decide to F/L size the many-times fired case to bring it back to “normal.” That doesn’t really work, the body die will bring it back some, but the brass will also spring back larger because that’s what brass does. So, even after using a body die, you have no clue about the internal volume. If you have to use a body die or if you have to F/L size the case at intervals, you do not have a consistent internal volume, especially between the load prior to the use of the body die and the load right after the use of the body die. You have no consistency from load to load.
Another reason you use the body die is to set the shoulder back some. This means that in the interval between the first firing and the time you use the body die, the shoulder has expanded, firing after firing. Another area of inconsistency, but it gets worse. This is actually how you damage your rifle.
Where going to stay with the bolt action here because I think everyone can agree that you really don’t want to neck size for semi-autos, levers and pumps. Why is that? Well, the common answer is these other action types do not have the camming action to chamber a neck sized cartridge. Imagine that.
Your bolt action should not be used to crush fit a fat cartridge with a too long neck either. If you do that consistently you are damaging your action; the lugs, the handle, etc. They are designed to hold the cartridge in place during ignition, to obturate the bore, not to coax bad cartridges into the chamber.
But it gets worse. If you have ANY resistance when you open the bolt and pull out the fired cartridge, you’ve got an overpressure situation. That can be caused by a bad load or by an ill-fitting cartridge, either way you are doing damage to your action. I know that a lot of neck sizers decide it’s time to use the body die when the bolt gets really hard to close or open; they are causing damage to their rifles, on top of getting inconsistencies from load to load.
A properly adjusted F/L resizing die for a single rifle should put the shoulder back about .001 to .002 from fired, squeeze the body and shrink the neck and mouth. When you load a handloaded cartridge, the bolt should close smoothly without any resistance whatsoever. When the shot is taken, you should be able to open the bolt without a hint of resistance then either. If there is any resistance anywhere, you have a problem, if it persists, you are damaging your rifle. If you open your bolt and hear a click at the top of the stroke, you’re really damaging your rifle.
Yes, I am an F-class shooter; yes, my action alone if $1,400, just the action. My barrels are chambered exactly to my specs using a dummy cartridge with the bullet seated exactly how I want it and just at the lands when the barrel is unfired. The chamber is tight, very tight.
Because of the tightness of my chamber, I could probably get away with neck sizing the case since it does not have much room for the brass to grow unlike factory rifles with their obese chambers. I F/L size my fired cartridges after every firing because I insist on the highest consistency between loadings and I absolutely must have the smoothest possible action travel. When I am in the middle of a competition, the very last thing I want is to be fighting with the action at every shot. I place the cartridge in the action and I close the bolt just before I fire. It’s ALWAYS as smooth as butter; no resistance. I then pull my 1.5 ounce trigger with the same finger that closed the bolt. When the round is fired and I finish my followthrough, I can open the bolt with the back of my thumb and pull the bolt back and fish out the fired case from the action. Imagine if I had to fight with the bolt at every shot.