When does neck tension cease to matter ?

[Laurie]

What happens if you eliminate neck tension altogether? or for that matter how about we eliminate the entire neck?

Not quite completely, but well on the way there, the .30 Wolfpup variant of 30BR for Hunter Bench Rest competition.

http://bulletin.accurateshooter.com/?s=.30+wolfpup&submit=Search

 

[dellet]

Not quite completely, but well on the way there, the .30 Wolfpup variant of 30BR for Hunter Bench Rest competition.

http://bulletin.accurateshooter.com/?s=.30+wolfpup&submit=Search

I have seen and love that cartridge because it also addresses the age old question of "how much bearing surface do I need in the neck"

Not much...

 

[Laurie]

I have seen and love that cartridge because it also addresses the age old question of "how much bearing surface do I need in the neck"

Not much...

I've long thought that myself having over the years obtained good results with bullets barely seated into the neck, much less than the usual half-calibre minimum depth that is supposed to be as shallow as you can/should go. This was invariably to counter serious throat erosion, or to use a bullet in a chamber with far more freebore than was suitable.

However, benchrest competition is a different and rather more demanding kettle of fish from every other variety of rifle shooting, so when this feature on the Wolfpup appeared I was surprised and impressed. A great result from going outside of the box. So far, I've not heard of anybody attempting to emulate it with say a vestigial neck form 6mm Dasher and long 105gn bullets though.

 

[HTSmith]

I never understood how neck tension can be the same for a bunch of rounds when I seat bullets none feel the same as the neck grabs them I think rifles seem to shoot better when touching the lands is because they release at the same time. I never liked that being there is to much pressure and wears the barrel out sooner so I use the Lee factory crimp die set the length to factory size. I do not bench shoot but from 200 -500 yds I have shot tiny groups that way with different calibers and rifles

Interesting. I once used the Lee Crimp die for Hornady 150 Gr FB Spire pts in a factory 30/06 that had a throat about a mile long. I crimped into the cannelure. It helped a lot. I never had the nerve to try a non cannelured bullet because it would deform the bullet at least somewhat.

 

[Richard Coody]

I've long thought that myself having over the years obtained good results with bullets barely seated into the neck, much less than the usual half-calibre minimum depth that is supposed to be as shallow as you can/should go. This was invariably to counter serious throat erosion, or to use a bullet in a chamber with far more freebore than was suitable.

However, benchrest competition is a different and rather more demanding kettle of fish from every other variety of rifle shooting, so when this feature on the Wolfpup appeared I was surprised and impressed. A great result from going outside of the box. So far, I've not heard of anybody attempting to emulate it with say a vestigial neck form 6mm Dasher and long 105gn bullets though.

I would say it is just another take on soft seating into the lands which i have had success with in the past. Jamming those vld's was standard practice for decades. Kind of eliminates issues with runout and with the bullet already started into the lands i would bet neck tension becomes less critical.

 

[Jennb]

Following this conversation. Most educational conversation in a while

 

[AlNyhus]

Not quite completely, but well on the way there, the .30 Wolfpup variant of 30BR for Hunter Bench Rest competition.

http://bulletin.accurateshooter.com/?s=.30+wolfpup&submit=Search

It'll never work..... -Al

 

[SPQR70AD]

Interesting. I once used the Lee Crimp die for Hornady 150 Gr FB Spire pts in a factory 30/06 that had a throat about a mile long. I crimped into the cannelure. It helped a lot. I never had the nerve to try a non cannelured bullet because it would deform the bullet at least somewhat.

I rarely use cannelured bullets and use the die on match bullets and smooth hunting bullets. I never worried about putting a groove in the bullets figuring plenty grooves put in by the rifling lol. also black hills match ammo and federal gold match ammo very accurate factory ammo with crimped bullets. I started using the die mostly for semi auto .308's and MI garand thinking neck tension was not enough in the violent feeding action then saw how it cut down groups size

 

[JimSC]

Not quite completely, but well on the way there, the .30 Wolfpup variant of 30BR for Hunter Bench Rest competition.

http://bulletin.accurateshooter.com/?s=.30+wolfpup&submit=Search

don't think that would work in a autofeeder

 

[AlNyhus]

don't think that would work in a autofeeder

And that's a good thing....not what it was designed for. -Al

 

[JimSC]

Just out of curiosity I wonder if any of you guys have ever seated a bullet the pulled it and measured to see if you have plastically deformed your brass. I stopped annealing a couple of years back and did that little exercise on a dozen or so cases (.22 to 30 cal) with 5 to 15 firings and all returned to the sized dimensions. Some of those rounds had been loaded as long as 6 months ago and some were just seated and immediately pulled. I always use a FL sizer with a bushing that give me .003 expansion from sized to seated and all contracted .003 when the bullet was pulled. The article by DamonCali I linked in my OP and his original The Science of Cartridge Brass Annealing are two of the best I have read on the science of annealing brass yet I still have major doubts as to whether it is needed or necessary. I almost fired up my Annealeeze last week after reading his latest article but stopped thinking that all of my brass now should have a uniform hardness and did the little test above to see if any of the cases were being plastically deformed and decided against it.

Anyway thanks all for some good posts and interesting observations

 

[chkunz]

One thing to consider, as you make the neck ID smaller, at some point the bullet becomes an expander manual. This can not be good for the bullet and you are no longer increasing "neck tension". Now, if someone can tell us what that point is that would be helpful.

 

[Richard Coody]

And maybe someone can explain to me why reloads that i load the night before a range trip shoot better than those i load a week or two earlier.

Now i am talking about a rifle that usually shoots in the 1's and 2's not a half moa rifle

 

[JimSC]

And maybe someone can explain to me why reloads that i load the night before a range trip shoot better than those i load a week or two earlier.

Now i am talking about a rifle that usually shoots in the 1's and 2's not a half moa rifle

size some new or old cases then seat some bullets and pull a few after seating then each day over the course of several days pull a couple of more and see if the neck is the same diameter as when it was sized or if it grew. I would be curious as to the results. Brass elasticity for any given batch of alloy is a constant and does not change with age, neither does the yield point. Might be placebo effect if you have convinced yourself that it matters. Try load loading ten rounds wait a week, load ten more then get a friend to mark the heads with a sharpie to differentiate the old from the new then leave them on the bench without telling you which is which. Shoot them and then ask the freind which was which

Placebo effect is very real. One study gave testers placebos and told them it was a placebo and even with knowing the results were skewed

A 2014 study led by Kaptchuk and published in Science Translational Medicine explored this by testing how people reacted to migraine pain medication. One group took a migraine drug labeled with the drug's name, another took a placebo labeled "placebo," and a third group took nothing. The researchers discovered that the placebo was 50% as effective as the real drug to reduce pain after a migraine attack.

https://www.health.harvard.edu/mental-health/the-power-of-the-placebo-effect

 

[dellet]

My personal experience is wide ranging, un-scientific and anecdotal at best. My shooting skills and the rifles I use prevent me from proving to what degree what I think is true, is actually true. With that said, if you look at the big truths the question becomes the title of the thread.

Annealing is a must.

The question is how much of the case and how often. This depends on the pressure of the loads and fit in the chamber before firing.

I shoot cases that are more than 100 years old, probably shot 1000's of times in multiple chambers, probably never over 35-40,000 psi. Who knows how many or the last time they were annealed before I got them. I have only split a few.

Compare that with new brass that is only partially or inadequately annealed that split on the first firing. Or "basic" cases that are drawn to length but not formed that split in the final forming process. Many wildcat cartridges need to need annealed a couple of times in the reforming process as well as some being fire formed. A 20% failure is common.

Somewhere between being able to form the case, have it survive between 10-1000 firings, or being able to shrink group sizes .1 MOA, annealing stops being critical, or in my case the shooter and his equipment aren't able to prove the difference.

300 Blackout sub-sonic.

Loaded neck diameter .328", Chamber .335"

This is an interesting study because using the same case and bullet combination, I can vary the peak pressure more than 50,000 psi without changing velocity more than the ES/SD of either combination.

The low pressure low load can be wiped down, re primed and charged, the bullet seated with finger pressure and a light crimp applied. Then ran through an AR multiple times.

Change powders, run the pressure up to 60,000+ and it's a race between the primer pocket and neck that has to be sized .010" each time, to see which gives out first. If the neck has been annealed, it will be the primer pocket.

The high pressure round has a much higher starting pressure, a cleaner release from the neck and most likely a much straighter start down the bore after a .250" jump as shown by the 70% reduction in group size.

Change the bullet from monolithic copper to cast and the group size is reversed. Jacketed bullets fall some place in between. Matching neck tension to powder and bullet can be critical and is probably over looked often.

There seem to be a lot of factors to consider answering the question of if and when to anneal, and how much neck interference to use, how much difference does it make.

My personal thought or answer to the original question is that the benefit of annealing or neck sizing adjustment stop, when it is no longer the weak link.

At my skill level, with the equipment I load and shoot with, at the distances I shoot, the benefits can almost be judged by case failure instead of group size measured in .001's on the target.

That in no way means having an understanding of what goes on and how to control that, is of no benefit. I just see it in .100's instead of .001's. Maybe someday I will play with the big kids.

 

[Richard Coody]

size some new or old cases then seat some bullets and pull a few after seating then each day over the course of several days pull a couple of more and see if the neck is the same diameter as when it was sized or if it grew. I would be curious as to the results. Brass elasticity for any given batch of alloy is a constant and does not change with age, neither does the yield point. Might be placebo effect if you have convinced yourself that it matters. Try load loading ten rounds wait a week, load ten more then get a friend to mark the heads with a sharpie to differentiate the old from the new then leave them on the bench without telling you which is which. Shoot them and then ask the freind which was which

Placebo effect is very real. One study gave testers placebos and told them it was a placebo and even with knowing the results were skewed

A 2014 study led by Kaptchuk and published in Science Translational Medicine explored this by testing how people reacted to migraine pain medication. One group took a migraine drug labeled with the drug's name, another took a placebo labeled "placebo," and a third group took nothing. The researchers discovered that the placebo was 50% as effective as the real drug to reduce pain after a migraine attack.

https://www.health.harvard.edu/mental-health/the-power-of-the-placebo-effect

Well that didn't heip much. For me it is very real. I can see it clearly on the target.

 

[BoydAllen]

In my experience, getting too wrapped up in theory can hurt you because it may lead you to not test because you "know" what the outcome will be. Test everything, and believe your targets. One variable in all of this is that different powders can respond differently to differences in neck tension.

 

[CharlieNC]

I think trying to relate modulus of elasticity and annealing to explain bullet seating characteristics explains only a small part of what is going on. Modulus characterizes the resistance to being stretched when the material is initially being deformed, in other words how tough is it to stretch a rubber band which will recover. But we all know the diameter of the case increases after the bullet is fired, in other words plastic or permanent deformation exceeding the elastic region of the material. When resizing the neck we are again surpassing the yield point where elasticity matters, that is we are trying to again permanently deform the neck from the large fired diameter to the smaller desired sized diameter. At some stage this may and does not happen as desired, the diameter is larger than desired, and the neck tension is less than desired; this is what annealing can correct. This problem is not strictly about elasticity, but the features of plastic deformation, and plays a role in neck tension.

 

[Laurie]

The low pressure low load can be wiped down, re primed and charged, the bullet seated with finger pressure and a light crimp applied. Then ran through an AR multiple times.

The first book I ever read on handloading was a slim Outdoorsman's Bookshop paperback by George C Nonte Jr whose title I can no longer remember at this remove. Although a basic primer on handloading for tyros, it had some fascinating chapters on fairly specialised practices including casting lead bullets for rifles, case re-forming and ultra-light loads.

In the ultra-light section, he recounted using a surplus 0.303" Enfield No.4 rifle in the 50s and 60s to rid a farm of pigeons. The reloading toolkit comprised a couple of wooden dowels, one with a small nail in the end and flat piece of steel. The fired case was decapped by the dowel/nail, no sizing was needed or done; repriming saw the case tapped onto an upturned primer sitting on the piece of steel, charge wasn't weighed - a cut-down 22 Short case with a wire 'handle' soldered on used as a dipper - and the bullet or in this case a double-O buckshot ball thumb-pressed into the case-mouth and Vaseline smeared over it. The propellant charge was a couple of grains of Bullseye and the rifle/cartridge was accurate enough for rooftop distance shots, but not so powerful that a miss would break roof tiles or chimney pots. Lee Loader tool principles but even cheaper. The cases never needed resizing and a handful were repeatedly reused over many years.

 

[mikeeg02]

Honestly Richard I think what your rifle and load does at the range is all that matters. Savage 6BR , Criterion barrel ?
Here is a 11 shot group from my Savage 6BR at 300, cases on 5th firing, no annealing, no brushing, no neck lube just dry tumbled, sized, then necks trimmed and seated on my humble Lee turret

View attachment 1160752

Not trying to be degrading, so please consider this helpful criticism, but if my competition rifle shot like that at 300, I would be either fixing the load or looking at the rifle, bullets, brass prep for reasons why it shot that big.

I also had a factory 6br savage rifle, and it would consistently hold an inch at 300. I've shot many 200-300--500y ground hog matches with it.

The tune on my customs should be holding 3/4" or less at 300.

I would strongly recommend you disregard your theory on the affects of annealing, and focus on loading consistency, and load development. You seem to be so hellbent on disproving the affects of annealing, I believe you're overlooking some important factors.