Neck sizing for accuracy

[johngibbs222]

I just neck size only, two reasons, the guns are ruger nos 1 and 3 and the second reason no case lube is needed as it's a crimp job. I also load for my 357 mag in my winchester but that has carbide resizing and the brass is cheap enough, even free at the range.
One thing I've learned from this thread is the desirability of placing the cartridge in the chamber in the same position as when it was fired the time before, I'd not considered this.
When I'm working up a load I always mark the bases of the case with felt tip, green for start loads, black for the first increment, blue for the second increment and red for max loads.
It'll be quite easy to mark the case base with a line of felt tip, I use R - P brass for my 223 and S & B brass for my 308, so a line through the "-" and "&" stamp and radially through the primer will give me a reference when I insert the carts into the chamber.
I'll start putting the factory loads into the chamber with the relevant stamp at the top of the chamber which will give me the best possible start for reloading.
FWIW the felt tip marks get cleaned off in my tumbler so I need a "system" to ensure repeatability if you get my drift.
I appreciate that a charging animal will increase the possibility of not getting the mark in the right place but man eating rabbits, foxes and deer ain't too thick on the ground over here so the odd inaccuracy won't be massive or matter too much.

 

[bigngreen]

You won't see guys setting LONG range BR records for size or score with neck sized brass from what I've seen, everyone I've seen is FL sizing and letting things align not forced alignment that has to be maintained perfectly though the whole process.
Every firing with neck sizing your chamber fit changes til you have to FL size then your back to firing it back out, I've seen this cause more case issue than keeping the case basically springing back and forth a couple thou. I retire cases and I'll loosed primer pockets, don't have head separation issues.

 

[redneckdan]

I've had good luck bumping shoulders .002" with a Redding body die then neck sizing with a lee collet die. I annealing about every 3 firings.

 

[Mikecr]

Every firing with neck sizing your chamber fit changes til you have to FL size then your back to firing it back out, I've seen this cause more case issue than keeping the case basically springing back and forth a couple thou.

This is just backwards of results produced by a better plan. And if you posted your plan, all of us with experience in this would see right off why it wouldn't work.

I'm not trying to imply anything negative about the '99%'. It's just reality.
People either know what they're doing with minimal sizing options, and make it work -with an upfront plan, or they don't know, and their hap-hazard attempts amount to screwing a pooch.

I use a standard factory Cooper in 223Rem for GH hunting. This is a pretty good example situation. With my load including FB BR bullets it groups in the 2s at 100, and 3/8moa grouping, with 1/4moa accuracy to 500yds. It's a 500yd GH gun that I set up for my son.
The Lapua brass prepped many years ago will last forever, and it's never been FL sized. I bump shoulders with a custom bump die, and bushing neck size with a Wilson.

Would FL sizing make the gun shoot better?
I seriously doubt it, as I doubt the gun could be expected to shoot better.
It might shoot as well FL sized, but I don't know, and can think of no reason that it would.
Would FL sizing be easier for a reloading plan?
Not in the long run, and it's not like my reloading is difficult. I don't have to trim, or re-anneal often, or replace cases. My extraction is good, pockets staying tight.
Why am I not whining about problems with neck sizing?
I don't have any problems. It's a 223Rem, small area, thick for diameter, and while a very unimproved design, it lends itself to extended minimal sizing. I also do not produce poor ammo in general. I measure everything ever time, taking no shortcuts.
For example, I don't surprise myself with a case tighter than others to throw a shot, nor with any similar issues -that we should never hear happening to competitors for sure.. That's my plan with 223Rem. And I've done it in 6BR, 6XC, and 260AI.
Would my plan work in standard 243Win or 308Win?
Not for long.
Would my plan work in 6PPC at competitive pressures?
No.
Would my plan work in 30-06 or 264wm?
Not possible at all.
When can you get away with true NSing only?
Only with an improved cartridge, tight to fitted chamber, an action providing enough barrel steel around the chamber, coned breech, bullet/powder choices and cartridge capacities no bigger than goals met within SAAMI/reasonable max pressures, custom dies, and attention to details in reloading.
That's enough to remove the '99%' from qualified in this..

 

[bigngreen]

Maybe we need to look at how you would acheive your same results with something that we actually long range hunt with like a 30 Nosler or 300 RUM, how is a neck sizing only strategy going to work out running at 65k for pressure shooting in a hunting situation?
What would be your plan on Dasher running well over that in 1000 yard BR comp?

 

[Mram10us]

Neck sized for my edge, ultras, etc before I got galled lugs on my edge and had to fix it. Cases got to tight and at the time I had no idea a bit of dust/sand had gotten in and with the tight fitting cases, galled the lugs. I started fl sizing, had no more problems and saw no difference in accuracy. To each their own. Try both ways and see what you like.

 

[bigedp51]

You are at the mercy of the quality of your cases and what happens to them when fired.
If your case wall thickness is not equal when fired the case warps, the case body can become egg shaped and even become banana shaped. Full length resizing reduces the chance of the case causing the bullet to be misaligned with the bore. And gives meaning to the saying "the cartridge should fit the chamber like a rat turd in a violin case".

Meaning a warped neck sized case is not going to improve accuracy. And a full length resized case will give the cartridge case some wiggle room to allow the bullet to be self aligning with the bore.

NECO CONCENTRICITY, WALL THICKNESS AND RUNOUT GAUGE

Also referred to as "The Case Gauge," this item is designed to measure:
1) The curved "banana" shape of the cartridge case;
2) The relative wall thickness variation of a cartridge case;
3) The cartridge case head out-of-squareness;
4) Individual Bullets - out-of-round "egg shape" and/or
curved "banana" shape (excepting very small bullets);
5) The seated bullet and cartridge runout of loaded rounds. The accuracy of any firearm is determined -- and limited -- by the quality of the ammunition shot in it. The effect of imperfections in ammunition is cumulative; each flaw adds to the influence of all others. Precision shooters spend much time and effort "uniforming" cartridge cases, using advanced techniques to eliminate variation. Yet until recently, one of the most important of these variations has not been susceptible to detection by any device readily available to marksmen.


Normal manufacturing tolerances cause brass cartridge cases to vary in wall thickness around the circumference of their bodies. Under the stress of firing, a case with such variation stretches more readily along its thin side, transferring more pressure to the bolt face at that point and introducing an unbalanced force which contributes to bolt whip and vibration of the barreled action in its bedding. This whip and vibration varies from one shot to the next as cartridges are fired with their thin sides randomly oriented at different angles, causing reduced accuracy. The problem is made even worse if the brass is too hard or springy to completely fireform to the shape of the chamber, in which event the greater stretching of the case's thin side will cause it to develop a curve along the length of its body. These "banana" cases cannot hold a bullet aligned with and centered in the bore, undercutting the effectiveness of the handloader's careful case preparation.

Fortunately the accuracy problems caused by wall-thickness variation can be minimized, or perhaps eliminated, if all cases are "indexed" -- fired with their thin sides always oriented the same direction in the chamber. This causes bolt whip to be minimized and consistent, and, while bullets will still be misaligned, they will all be misaligned the same way, which often produces accuracy like that of perfectly aligned and concentric ammunition.

All we need to index cases is a means of accurately locating each case's thinnest point. This is not possible with traditional micrometers or other measuring devices used by handloaders.

The patented NECO Concentricity, Wall Thickness and Runout Gauge™ is a unique tool. In addition to permitting all the runout measurements possible with other concentricity checkers, it features a "chord anvil" fixture which allows the handloader to measure the wall thickness of cartridge cases, to determine its uniformity, and to precisely locate the thickest or thinnest point in each case. Brass can then be sorted according to uniformity, and permanently marked for indexing.

Until the advent of this new NECO gauge, indexing and checking for straightness procedures have been neglected because of the difficulty of the necessary measurements, but are now very easy to perform. Several large commercial ammunition manufacturers have adopted the NECO gauge as a standard laboratory tool for quality control purposes.

 

[Riflehunter1776]

forget your lying eyes and years of results. We have a new fit-all theory!

 

[bigngreen]

I've watched to many 2 inch groups shot at a 1000 yards to go back to methods that don't achieve that level of consistency. You can do a lot of stuff that you can see great results at closer ranges but crank on the range and start actually measuring results INCLUDING those nasty flyers and it boils it down and weeds out the things.

 

[bigngreen]

forget your lying eyes and years of results. We have a new fit-all theory!

Those methods are no longer competitive at long range when measuring results, why so resistant to learning? Guys who chase thousandths of an inch at a 1000 yards do not neck size only, at least anyone remotely competitive!!

 

[Riflehunter1776]

It seems that lack of attention to detail is why some people might prefer a generic one-size-fits-all approach. as I said previously,

I have some rifles that prefer Neck sizing and will flat outshoot the same load which was "bumped". I have some rifles which shoot better bumped. There is no universal answer which fits every single rifle without fail. find out what works best for you by trying it.

 

[jbs2014]

With my RCBS dies on my Weatherby cartridges I set the shoulder (radius) back .002-.003. I anneal with the AMP after every firing. I do the same with the Cheytac cases. I can't find anyone who makes a bushing type die for the Weatherby cases.

When I first started reloading I followed the RCBS instructions and set the die and press to cam over. I found that this was really overworking the brass, I think if memory serves correct, it was set back was .010 or more. But, with this process, I did not have to alter my powder charge to get the same velocity results (as new brass) as I do now with the .002-.003 setback. With the .002-.003 setback, I had to drop the powder charge by .5 grain to get back in the same velocity node. I am told that the .010 + setback shortens brass life significantly. The Cheytac dies don't push things back near that far even when set to cam over.

Do any of you find that you have to adjust your load from going from new brass to once fired, set back .002-.003 brass?

Where does a person acquire these mandrels that were mentioned previously? Do they attach to the sizing die? Think they come in .408 and .510?

Thank you

 

[LDHunter]

It always seems that anyone wanting to discuss case prep ends up getting beaten about the head and shoulders by "how the bench rest shooters do it" which in my opinion can be instructive at best but my experience has shown a heck of a lot of rifles that shoot well under a 1/2" group at a hundred and brass life being about 15 loadings for non-magnum cartridges and 5 loadings for magnum cartridges and that's more than enough for me.

I have literally loaded thousands of rounds with the Lee Collet neck size only dies and don't have problems chambering rounds because I don't load hot loads for a particular cartridge and I simply discard brass before I ever need to anneal or FL size.

I like to read about how the bench rest guys do it but very little of that truly applies to my shooting or loading or hunting.

Also if you have to index your cartridges because your chamber is out of round then in my world it's a rifle problem and I'll rebarrel the rifle and have a precision gunsmith do it so my chamber will actually be ROUND not egg shaped.

In my opinion the kind of precision that benchrest shooters demand has very little to do with hunting where under field conditions it is FAR more important to pay attention to even getting a somewhat stable rest and reading your wind on the fly with no wind flags. You can chase accuracy for years and ruin your eyes staring at micrometers and agonizing about runout and thousands of an inch but when you get to actual field conditions shooting all that becomes a very very small part of the equation.

If your rifle is truly built right then hunting accuracy even at quite long ranges is pretty darn easy to achieve sometimes even with factory ammo.

 

[Mikecr]

Do any of you find that you have to adjust your load from going from new brass to once fired, set back .002-.003 brass?

With respect to reloading, new brass doesn't count. It's only the way it is for one shot. 2-3thou is excess bump, 10thou is dead wrong.