ELR reloading article.. interesting data

[1stmar]

An article in “The complete book of reloading” 2019, discusses precision reloading for king of 2 miles with 3-4 competitors, specifically Tubb, Powell, Smitchko. In this article I found a couple of things interesting:
1. The author (eduardo abril de Fontcuberto) measures concentricity with a neco device and he compensates for runout by using a hammer to true concentricity. I equate this the hornady concentricity guage that applies pressure to the high side of the round to reduce runout

2. Though many of the competitors discuss how critical neck tension is, no one mentioned annealing. Doesnt mean that they dont do it.

I found the above 2 items seemingly in conflict, hammering the round into concentricity seemingly would affect neck tension. And in 4 pages of content which talked extensively about low sd, runout and neck tension i found it curious that there was no mention of annealing by anyone.

[hounddawg]

probably because no reputable test has ever been published on the effects of annealing cases. Litz did a limited study in one of his books on .308 and .223 and found no changes between brass that had been annealed every firing firing for ten rounds and that which was never annealed.

Modern Advancements in Long Range Shooting Vol. 2

https://www.amazon.com/Modern-Advanc...FA6S6NAVKD4S1Q

[mikld]

I would think they use "hammering" generically. Not really meaning hammering hard enough to distort or form any metal, just tapping the round (probably the bullet) to straighten the round...

[Jim Watson]

Interesting that forcing into alignment is considered as good as alignment by choice of components and dies.

[dahermit]

Interesting that forcing into alignment is considered as good as alignment by choice of components and dies.

When I was obsessed with concentricity of rounds/alignment, I found that despite quality dies and components, I still had to sort the end product (rounds), inasmuch as there was a variance in concentric no matter what dies I used. I used rounds with runout of .003 and less for competition and shot the rounds of more than .003 run out for practice.

[hounddawg]

When I was obsessed with concentricity of rounds/alignment, I found that despite quality dies and components, I still had to sort the end product (rounds), inasmuch as there was a variance in concentric no matter what dies I used. I used rounds with runout of .003 and less for competition and shot the rounds of more than .003 run out for practice.

proper die and reloading procedures make it a lot less work however. I only check match rounds and it is a lot easier to tweak 3 out of 50 into alignment than 3 out of 5. My tolerance for match rounds is .001

[Unclenick]

Dahermit's numbers are pretty reasonable. Figure 0.003 TIR is 0.0015 of tip-tilt off-axis, and that should not be able to cause drift of more than around 0.2 moa radially away from a specific POI at 100 yards with most common bullet designs. Still pretty good precision.

I've been able to get down to about 0.002 TIR without neck turning and about half that with neck turning. PITA, though and only worth bothering with for some secant ogive designs.

The OP referenced conjunction of the NECO gauge and a hammer, which I found humorous. The former is a pretty delicate instrument and the latter is, well, not. NECO does sell a universal correcting fixture, but I find I can drill holes in a piece of hardwood that I clamp to the bench that seems to work, even it isn't as nice. As long as it doesn't mar the bullet or burr the case in the correction process, it is adequate. You do have to get the feel of it, though that doesn't take long.

1stmar,

What determines how hard the brass grips the bullet is its modulus of elasticity, a measure of how hard it is to stretch within its elastic limits, and the yield point. Basically, you can make the interference fit to the neck tighter and tighter to increase bullet pull by elastic deformation up to the point the metal yields (plastic deformation), after which the metal gets bigger without increased elastic force being applied. If you go to Matweb and look at different tempers of cartridge brass (different levels of annealing), you discover the modulus of elasticity is the same for all of them. In other words, the elastic force is the same regardless of annealing. What changes with hardness is the yield force, which is how much pressure you apply before it deforms plastically. So, a neck can be sized smaller to get higher bullet pull only until the amount the bullet expands it reaches the yield point of the brass. Since annealed brass has a lower yield, if you sized necks smaller and smaller, you would reach the limit below which no increase in bullet pull is achieved sooner with annealed brass. But if neither your annealed brass nor your work-hardened brass is being stretched to its yield point by the bullet expanding the resized neck, then, for cases with the same neck wall thickness and bullet seating depth, bullet pull will be the same. I'm convinced that sameness of the modulus of elasticity across different hardnesses is why Bryan Litz saw no difference in annealed brass in the tests he ran.

That said, there may be some hidden advantages to annealing. One thing is it should take a little less effort to straighten a bullet in an annealed case. Another is it should respond better to being straightened in your sizing die. Another is burning the carbon out of the neck should make its lubricity with the bullet more consistent, which would improve consistency of bullet pull. Another is the oxide layer, which is known to fend off corrosion of the brass in corrosive atmospheres, may help the loaded rounds keep from developing excessive bullet pull. Lots of possibilities are out there. Annealing cautions would include that over-annealing could reduce the yield point so much that even small amounts of stretching surpasses it and bullet pull is thereby reduced even for normal loading procedures (I haven't calculated that to see it's practical to make happen). Another is just that over-annealed brass develops neck splits more rapidly than properly annealed brass, so unless you anneal very frequently you can lose cases.

I would like to see someone do a comparison of FL resized cases, on not annealed until it splits and the other annealed ever time, to see which one develops the "dreaded donut" faster.

[1stmar]

Thanks unclenick. The hammer did have a rubber head fwiw. Your explanation mirrors my experience. I have used the hornady concentricity guage w mixed results probably because in some cases i have exceeded the plasticity and affected neck tension. I had since stopped using it and largely have found better tools and processes that keep run out to .003 or less.

Im thinking lighter neck tension generally leads to more consistency as the brass is worked less.

[oley55]

this Fli-rite concentricity gauge uses a hammering to correct concentricity.

http://www.premieraccuracy.com/gauges.html

[cw308]

A good full length die is all that's needed , Concentricity will average .001

[mikld]

Watched most of the video, and from what I saw, the term "hammering" is a very, very loose description. I use a Forster Co-Ax and Lee dies for my 308 ammo. I bought a Hornady concentrically gauge just to see, and I could have saved my money, no cartridge went over .0015"...

[oley55]

ok, how about; "lightly thunking with a nicely weighted chunk of steel"?

Clearly a bit of practice and some art to control the amount of thunk was displayed in the video.

[mikld]

I'm not trying to make a point, just replying to the original question about "hammering on a cartridge loosening neck tension". My statements are in regard to the tool in the video does not "hammer". Hammering will loosen neck tension (ever loosen a bullet in a case by hammering on the neck, evenly around the circumference to stretch the brass, thus loosening the neck tension?). No dog in this fight, just replying from my standpoint after working with metals, machinery for 60 years...

[Unclenick]

It's a form of dance. The fellow in the video is tapping.

I think this is about gradual vs. suddenly applied corrective force. Not an issue as done in that video. Both take practice. Both can work.

[RC20]

Though many of the competitors discuss how critical neck tension is, no one mentioned annealing. Doesnt mean that they dont do it.

I don't anneal to do anything with tensions (though it gets nasty to seat if you don't and the case last long enough

My prime goal is to make brass last (no splits)

The other is so I don't crunch the case while putting a bullet in it.

On the other hand, my best target two weeks ago was the one that was a 3/4 inch group.

One it was a nice pattern, two it was in the fog and I was hard put to be sure the square was where I thought it was.

[1stmar]

The picture in the article showed a hammer w a runber cover over the head. Looked like a large tack hammer. I would expect given the perceived weight of the hammer the strikes would be much more material than the tapping in the fli rite video.

[mikld]

Need to apologize here. Sometimes I get wrapped up in trying to explain myself, and it sounds like arguing. Not meant that way. I guess I was just trying to explain my thinking of what a particular term means. All in all, no big deal. Apologies Gentlemen...

Perhaps sometimes I pick the heck outta them nits...

[hounddawg]

Perhaps sometimes I pick the heck outta them nits...

I thought that was what God invented internet forums for

[reynolds357]

Bench rest shooters don't tell their secrets. Many will help you along to a point, but once you get there, you are on your own. The article tells nothing that is not basic well known knowledge. The most accurate B.R. shooter I know (currently holds a world record and has held several) shoots with virtually no neck tension.

[reynolds357]

A good full length die is all that's needed , Concentricity will average .001

I guarantee they have "good" dies.

[RC20]

Some writer interviewed a fairly large group (8-12) of bench rest shooters.

One guy would swear X was the end and be all and the next guy said it was Y and no two agreed on all of what was important.

It was pretty funny. Seems like faith has a lot to do with it.

[hounddawg]

The most accurate B.R. shooter I know (currently holds a world record and has held several) shoots with virtually no neck tension.

I would bet a dollar he is shooting short range benchrest with a 6PPC or 30 BR custom rig. Plus the guy would probably be a winner no matter what kit he is running. Gear can only get you half way there if you can't read the environment and have perfect technique you are screwed .

In mid and long range I have seen targets cleaned with double digit X count shot with factory ammo in the right hands and a good rifle. For that matter a while back a guy came to a 300 match with a 6 CM Ruger Precision with less than 50 rounds through it and some bulk Hornady ammo and shot a 199

Back to topic I bought a bushing die and played with neck tensions last year and found what works for me in my rifles, they are garage built F class rifles but they get me by for my skill level. I believe that what works for one rifle/cartridge/discipline is not the universal truth. You have to find what works for you in your loads

Just my opinion

oh and a edit, there are some benchresters that hold clinics around the country. Not saying they don't still hold a bit back but if you have the drive and the resources to pursue it the only thing that will limit you is your abilities

[F. Guffey]

And all I use is 'bullet hold'; when it comes to bullet hold I want all the bullet hold I can get; because! ? I can measure bullet hold in pounds. Again, as I have said it is possible to measure interference fit and crush fit but there is no gage made to measure tension except in pounds.

2. Though many of the competitors discuss how critical neck tension is, no one mentioned annealing. Doesn't mean that they don't do it

.

I have given up on reloaders because it so difficult to get them away from the key board. And; they would have to find some way to measure the effort necessary to seat a bullet as in before annealing and again after annealing with a tool that does not exist as in a seating die that measures bullet seating effort in pounds!!!! Wait! THE PRESS DOES EXIST, problem, it measures in pounds

F. Guffey

[hounddawg]

annealed vs unannealed seating in a labratory

https://www.ampannealing.com/article...he-microscope/

now lets see them do some real world testing with a good chrono by a world class shooter because that is the only test that matters

Forums are a good place to kill time, polish egos and argue angels dancing on the head of a pin theories that will never be answered but putting holes in targets are the only real tests

[F. Guffey]

I have given up on reloaders because it so difficult to get them away from the key board. And; they would have to find some way to measure the effort necessary to seat a bullet as in before annealing and again after annealing with a tool that does not exist as in a seating die that measures bullet seating effort in pounds!!!! Wait! THE PRESS DOES EXIST, problem, it measures in pounds

Again; Your link just about covers it with one exception, I want to know how much effort is required to seat a bullet. I can not find tension effort like 15 tensions or a chart that converts tensions to pounds, if annealing softens the neck there is no chart that guides the reloader through the change in effort to match interference fit or crush fit.

There are presses available that measure the effort necessary to seat a bullet; the presses measure in pounds.

F. Guffey