My theory on neck tension. Am I way off base?

[Yerman]

I'm trying to get my head around the whole neck tension thing for precision handloading. Here is my theory, please tell me if I'm wrong.

So I just spent all this money on a neck turning kit from K&M. As I'm going through the process, I realize that the reason I am doing all of this is so that when I run my brass through my bushing dies, I will get uniform next tension because the thickness of the brass is the same all the way around and when my bushing squeezes the neck, it will be uniform all the way around the bullet.

Then I start thinking about how full length sizing dies run an expander through the case neck to even out the inside of the neck. Well, if the inside of the neck has uniform tension on the bullet, the only down side is that I can't control the neck tension with bushings. Furthermore, if using and expanded ball evens out the neck, why bother going through the whole neck turning process? I mean, who cares if the outside is uneven as long as the inside of the neck is uniform on the bullet right?

So I start to look in to expander balls and I come across Whidden Expander Kits. If I can order a kit with different size expander balls and control the neck tension, why am I screwing around with all of this neck bushing / neck turning business when I can just get the kit and have the same results?

What am I missing?

 

[Threadcutter308]

Inconsistent neck wall thickness can lead to the bullet not being in the exact centerline of the bore. It is one, but not the only factor of why you want to neck turn. Once you have turned your necks, using a specific size neck sizing bushing should give you consistent neck tension. There seem to be more bushings in different sizes than expander balls available, hence, more versatility.

 

[black5.3]

Neck turning will help create more consistent and "perfect" brass to reload.. with that being said most people that start turning necks later find out its not necessary unless you have to turn necks for your chamber.. i have found through a little personal research that in my particular case and for my long range rifle. I get what what i need from using quality brass, annealing every 1-2 firings, FL sizing with a forster benchrest die with the expander madrel removed and then getting my necks right with a 21st century expander mandrel... when i started doing this my targets and magnetospeed v3 showed me it was working.

 

[Juggerxxx]

If the necks are all the same thickness on all your cases you don't need to use the expander ball if you are using bushings. The bushings then do their intended job of dictating a consistent diameter of your choosing for a desired neck tension. Some people believe the expander ball may deform the neck when pulled back out of the case.

 

[Sig Marine]

I'm trying to get my head around the whole neck tension thing for precision handloading. Here is my theory, please tell me if I'm wrong.

So I just spent all this money on a neck turning kit from K&M. As I'm going through the process, I realize that the reason I am doing all of this is so that when I run my brass through my bushing dies, I will get uniform next tension because the thickness of the brass is the same all the way around and when my bushing squeezes the neck, it will be uniform all the way around the bullet.

Then I start thinking about how full length sizing dies run an expander through the case neck to even out the inside of the neck. Well, if the inside of the neck has uniform tension on the bullet, the only down side is that I can't control the neck tension with bushings. Furthermore, if using and expanded ball evens out the neck, why bother going through the whole neck turning process? I mean, who cares if the outside is uneven as long as the inside of the neck is uniform on the bullet right?

So I start to look in to expander balls and I come across Whidden Expander Kits. If I can order a kit with different size expander balls and control the neck tension, why am I screwing around with all of this neck bushing / neck turning business when I can just get the kit and have the same results?

What am I missing?

Purpose...What type of shooting are you doing? Every decision I make regarding my shooting and reloading is always related to purpose. I do not want to spend my time "putting lipstick on a pig" if my end goals do not require it. I shoot the occasional F-Class match but primarily shoot steel. My needs do not require the extra time spent turning necks, weighing/measuring bullets and cases, measuring concentricity, using an arbor press to measure neck tension/bullet seating pressure, etc.. As another member said, use quality brass, anneal and use quality dies and much of the neck tension issue will take care of itself. I've tested my ammunition and loaded with and without an extender ball. I could see no difference on the target or on the chrono numbers. All of my loads have ESs under 15 and SDs under 8. With these results, I can't justify the additional work for the small amount of gain I may get.

 

[TripleBull]

Then I start thinking about how full length sizing dies run an expander through the case neck to even out the inside of the neck. Well, if the inside of the neck has uniform tension on the bullet, the only down side is that I can't control the neck tension with bushings. Furthermore, if using and expanded ball evens out the neck, why bother going through the whole neck turning process? I mean, who cares if the outside is uneven as long as the inside of the neck is uniform on the bullet right?

I don't necessarily think of an expander's effect being to "even out the inside of the neck". If you want to read a somewhat fanatical description of how the brass is moved around in the shoulder/neck region when using a FLSD + expander ball, pick up a copy of Glenn Zedeker's "Handloading for Competition":

https://www.amazon.com/Handloading-...&qid=1506003408&sr=8-3-spell&keywords=zedeker

He also discusses neck turning at length. Warning: it's an awkward book to read.

One of the key effects of full length sizing with an expander ball is that brass in the shoulder/neck area is worked (and therefore hardened) and physically moved differently than when using a non-full length sized bushing die. With a FLSD + EB, you're going to need to trim the case more because brass migrates towards the mouth. Think about the expander ball pulling brass forward against the shoulder/neck constriction of the FLSD. Suffice to say that there are pros and cons to the different approaches and if you look around the threads here, you'll see how many guys use a honed FLSD with the expander removed, and they use a mandrel as part of the neck shaping/sizing. If you can work the brass less, you're better off, regardless of whether or not you anneal.

 

[Citius7]

Neck turning will help create more consistent and "perfect" brass to reload.. with that being said most people that start turning necks later find out its not necessary unless you have to turn necks for your chamber.

This.

Taking material away from your brass makes them last not as long as they would if you had just shot em. I have consistent sds in 3’s in 4 calibers and they all have the ability to shoot 2 inch groupings at 600 yards. I say that to say there are better ways to spend your time and money on than turning your expensive material. I don’t really know how much more turning would do for me. But if it did anything more for me. It would not do much. And it would def not be worth it.

 

[JoeBUtah]

Purpose...What type of shooting are you doing? Every decision I make regarding my shooting and reloading is always related to purpose. I do not want to spend my time "putting lipstick on a pig" if my end goals do not require it. I shoot the occasional F-Class match but primarily shoot steel. My needs do not require the extra time spent turning necks, weighing/measuring bullets and cases, measuring concentricity, using an arbor press to measure neck tension/bullet seating pressure, etc.. As another member said, use quality brass, anneal and use quality dies and much of the neck tension issue will take care of itself. I've tested my ammunition and loaded with and without an extender ball. I could see no difference on the target or on the chrono numbers. All of my loads have ESs under 15 and SDs under 8. With these results, I can't justify the additional work for the small amount of gain I may get.

I've pondered the neck tension/ turning thing for some time, and basically came to this same conclusion. Nothing wrong with a ragged hole at 100 yards, but that distant clang is where it's at for me; don't need to turn necks for that....

 

[J!m]

I have "handloading for competition" as well and it is great to address all the how any why questions that come up when you learn about some technique used in loading you were not familiar with.

I learned a few things, and one of those is: learn all the rules so you can learn to break the rules. In other words, learn all you can, and then apply it as necessary to your particular need.

I have enough tied up in loading equipment to buy a new car. But I learned, after wasting many hours of my life, a system that works for me, and I stick with it.

Virgin brass: full length size and trim neck to print max OAL. Sometimes the brass doesn't reach max but that's ok. Also uniform primer pockets and flash holes.

Fire form. I don't full length size again. I don't anneal. I DO carefully inspect after every firing. I do check OAL and trim any over print. And I tumble them (before anything else so cracks are easier to see).

The way way I figure it, and it seems to work, if I don't knock the brass back, it's not going to bulge back out in every firing, so, less working of the brass. Yes, I get neck cracks, but I scrap those. I still get (up to) five firings before fall out.

I use a bushing die to crimp the neck. And I crimp it just enough to hold things together. I shoot paper, so my cartridges each have a cube in a plastic box, tips up. For hunting you must hold the bullet in better than I do for targets. And i seat the bullet as shallow as possible- max COAL which I check 100%. Im well off the lands (in my old rifle) and they can mag feed, although I was single feeding anyway. They are a bit delicate...

Tricke the powder and weigh every charge. That sucks but I don't know if a more accurate way to do it. The rest of the process is just careful set up but trickling powder takes forever...

hand seat your primers. You need to feel the resistance is consistent. Some pockets can get loose and you want to set those aside or mark the end with black marker. They will be for non critical use and scrapped when they come back to the bench.

If you have several rifles in the same caliber, they each have a preferred load anyway. Color code the bases for each load/rifle.

Fire forming to your chamber is the easiest and most accurate way (for me) to tailor the cartridge sizing to the rifle. Working the brass as little as possible preserves it too. But no brass lasts forever. Annealing does re soften it to avoid cracks, and some guys get 10 or more firings this way. But for .308 even Lapua brass is so cheap I just run it until it's done and recycle it.

A new new idea I heard of that may or may not be in the book, is to have your smith make you a chamber die with the drop from your barrel and the same reamer he uses on your barrel. I have no idea if that would be better than fire forming but since I was writing a novelette here anyway, why not add it in.

 

[flyright]

I agree with Jim except, I don't uniform primer pockets or flash holes, COAL can be a bugger and varies with the particular barrel (don't mind experimenting with that) some powder measures drop very accurately, and primers seated via my Dillon work fine. I've found this to work easily for less than .5 moa for quite a few rifles with what I'd call a "good" barrel but some rifles you have to work very hard at (with all of Jim's parameters and more) to make shoot well. Some rifles/barrels just seem to be very forgiving and those are my favorites. Some require all that sh!t - I get quite tired of fussing with some of those so I will just sell or re barrel. Maybe I'm not very patient but I have many shooting friends that have shot barrels out trying to get them to shoot. Much less time, frustration, and probably money to re barrel or re gun when you have one that requires extensive experimentation and precise attention to detail for EVERY variable in reloading to get a it to shoot well.

I remember being at the range with a friend of mine - Bill (BR shooter with many wins) struggling to shoot a hole with his new Sako action (21 lbs as I remember) bench rest rifle several years ago. He went through about 5 different PRECISELY loaded rounds he had worked up and none would do much better than 1" @ 100 yds. He came from a shooting family and his nephew showed up at the range a bit later. The nephew had a Rem 700 ADL .243 and 20 hunting rounds loaded on a Dillon 550. The nephew knew his uncle was a great shooter and asked him to shoot a group for him to test the load. Bill proceeded to shoot one slightly ragged hole at 100 yds. Bill turned to me and said "Now ain't that some sh!t".

 

[ZiaHunter]

Neck tension is basically a function of neck wall thickness and brass hardness uniformity. I turn necks for my F Class rifles for a number of reasons. I want the neck wall thickness to be same and provide a specified clearance in the chamber neck, eliminate the use of the expander plug when sizing and minimize runout. I anneal after every firing to control brass hardness. Neck tension is checked using an arbor press with a psi gauge and rounds are sorted by tension. Yes this very anal but when you need to minimize vertical at 1000 yards it becomes necessary. For shooting steel probably not necessary especially if using quality brass such as Lapua but if you want to do it it certainly won't hurt. When loading my 338 for ELR I use the same case preparation and loading techniques I use for F Class with exception of using the arbor press.

 

[flashhole]

Pulling the expander ball up through the case neck will not alter neck wall thickness. It will only expand the inside of the neck to the desired size.

Neck turning makes the neck wall thickness the same all around the neck uniforming the brass and the tension it places on the bullet. Better quality brass may not need turning at all.

I get the best results neck turning brass I have re-sized or re-formed. For example I use 223 military brass to make 221 Fireball brass and military 30-06 brass to make 25-06 brass. In both cases (no pun intended) I end up with excessively thick necks that get turned to a specific thickness of my choosing. I also use the K&M tool and inside ream at the same time I outside turn. My process makes very uniform brass and the extra effort shows up on the target.

 

[J!m]

Maybe my post seemed more involved than the actual process...

i shoot, tumble brass, inspect for cracks, inspect OAL of the case, trim to print (if needed), hand seat a primer, measure powder into the balance pan, topping to exact charge with the trickler, dump that in the case and seat my bullet.

I think its its a simple process. Once you get in the groove it's not a big deal.

Only for new, un-fired brass do I full length size, uniform pockets and flash holes. Those operations are done once only.

Hopefully that hat clears that up.

Consistency=accuracy.

 

[Supersubes]

I'm trying to get my head around the whole neck tension thing for precision handloading. Here is my theory, please tell me if I'm wrong.

So I just spent all this money on a neck turning kit from K&M. As I'm going through the process, I realize that the reason I am doing all of this is so that when I run my brass through my bushing dies, I will get uniform next tension because the thickness of the brass is the same all the way around and when my bushing squeezes the neck, it will be uniform all the way around the bullet.

Then I start thinking about how full length sizing dies run an expander through the case neck to even out the inside of the neck. Well, if the inside of the neck has uniform tension on the bullet, the only down side is that I can't control the neck tension with bushings. Furthermore, if using and expanded ball evens out the neck, why bother going through the whole neck turning process? I mean, who cares if the outside is uneven as long as the inside of the neck is uniform on the bullet right?

So I start to look in to expander balls and I come across Whidden Expander Kits. If I can order a kit with different size expander balls and control the neck tension, why am I screwing around with all of this neck bushing / neck turning business when I can just get the kit and have the same results?

What am I missing?

The expander ball or mandrel pushes the defects to the OD, and sets the ID. If you take a bunch of cases with uneven necks and run them over an expander, they come away from that just as uneven as they started, and they will be just as uneven while grabbing bullets.

Im not familiar with the whidden kit your speaking of, but changing the expander sizes will change the neck ID, and the relative amount of neck tension(a range based upon the neck wall variance). Neck turning works for sure, but only you can determine if your results on are worth the effort. Except for special circumstances like wildcatting, I avoid it because I think its a shitty task. I use premium brass, I anneal frequently, and im happy with my velocity spreads.

 

[MarinePMI]

IME neck tension comes into play when you have excessive free bore/leade in the chamber(or neck erosion). Most of the rifles used in this type of competition will be tight enough that neck tension as little effect. That being said, in a milspec or sloppy factory chamber, there often is a noticeable difference in accuracy when messing with neck tension (whether that be turning necks or crimping rounds with something like a Lee factory crimp die).

Any easy (well, from a testing perspective any ways) to see the difference in the effects of neck tension, is when doing accuracy testing with belt fed weapons. Due to the sloppy nature of the chamber (to ensure reliability), accuracy improvements are VERY (as in dramatically) apparent when neck tension becomes more uniform. This is why people will often see adhesive applied to the bullets (asphalt gray looking stuff), and can be seen in unfired ammunition around the case neck of belted ammunition. Sometimes (depends on the manufacturer) primer sealant is used as an adhesive on the bullet.

For members of this board, and the rifles that they shoot, there is probably little (if any) practical value. The rifle chambers are tight, and the targets are fairly large.

JMTCW...YMMV..