Neck tension

[Firearmsunlimited]

With a .224 bullet and brass with .014 necks would you use .001 or .002 neck tension? Brass is new and I re-anneal after every 5 firings so spring back isn't a real concern.
Thanks

 

[KMart]

Let your rifle tell you what it likes best, .001 or .002

 

[Dave M.]

With a .224 bullet and brass with .014 necks would you use .001 or .002 neck tension? Brass is new and I re-anneal after every 5 firings so spring back isn't a real concern.
Thanks

Why are you only considering .001” or .002”? There are other factors that we really need to know before anyone should attempt to answer this question, like:
1. Seating depth relative to the lands?
2. High pressure (aka hot loads)?
3. Bolt action or AR?
4. Mag feeding?

lastly, I’ve recently found higher neck tension provides excellent and repeatable ignition and accuracy (0.004” plus)
Dave

 

[bozo699]

Why are you only considering .001” or .002”? There are other factors that we really need to know before anyone should attempt to answer this question, like:
1. Seating depth relative to the lands?
2. High pressure (aka hot loads)?
3. Bolt action or AR?
4. Mag feeding?

lastly, I’ve recently found higher neck tension provides excellent and repeatable ignition and accuracy (0.004” plus)
Dave

^^^^^^^ This!…
Wayne

 

[ronemus]

I take a different approach than most folks on this forum. Brass will flow elastically (no permanent deformation, also referred to a spring back) and inelastically (permanent change), only the elastic change contributes to bullet retention; any more change in diameter is just using the bullet as a neck expander. Bullets make poor expanders because the force required can deform them (usually inconsistently). I shoot moly-coated bullets (another topic that is more akin to religion than science) and want to maximize bullet retention while simultaneously minimizing runout and bullet deformation. I use Hornady full-length sizing dies with custom expanders that are full bullet diameter; the elliptical expanders are very similar to mandrels in their effect on the brass - gradual tapers at both ends combined with a cylindrical center section. Since the expander is of full bullet diameter, it takes care of the inelastic expansion of the neck and leaves the entire elastic component, thus maximizing bullet retention. This approach has worked well for me to produce ammunition that performs well. My reloads have little runout and perform well on target. There is lore that expanders in sizing dies will "pull the neck out of shape and induce runout." I find that to not be the case with Hornady dies and brass lubed with a very light coat of Imperial Sizing Wax on the exterior of the case (smaered on with fingers) and inside the neck (applied with a cotton swab). I'm sure many will find fault with this approach, but it works for me.

 

[Firearmsunlimited]

Why are you only considering .001” or .002”? There are other factors that we really need to know before anyone should attempt to answer this question, like:
1. Seating depth relative to the lands?
2. High pressure (aka hot loads)?
3. Bolt action or AR?
4. Mag feeding?

lastly, I’ve recently found higher neck tension provides excellent and repeatable ignition and accuracy (0.004” plus)
Dave

Not that seating depth in relationship to the lands has anything to do with neck tension but +.005.
Mid pressure loads
Bolt action
Feeding single rounds
In the past I have found that .003 is the breakover point that starts to negatively impact accuracy with the exception of VLD's.

 

[Firearmsunlimited]

I take a different approach than most folks on this forum. Brass will flow elastically (no permanent deformation, also referred to a spring back) and inelastically (permanent change), only the elastic change contributes to bullet retention; any more change in diameter is just using the bullet as a neck expander. Bullets make poor expanders because the force required can deform them (usually inconsistently). I shoot moly-coated bullets (another topic that is more akin to religion than science) and want to maximize bullet retention while simultaneously minimizing runout and bullet deformation. I use Hornady full-length sizing dies with custom expanders that are full bullet diameter; the elliptical expanders are very similar to mandrels in their effect on the brass - gradual tapers at both ends combined with a cylindrical center section. Since the expander is of full bullet diameter, it takes care of the inelastic expansion of the neck and leaves the entire elastic component, thus maximizing bullet retention. This approach has worked well for me to produce ammunition that performs well. My reloads have little runout and perform well on target. There is lore that expanders in sizing dies will "pull the neck out of shape and induce runout." I find that to not be the case with Hornady dies and brass lubed with a very light coat of Imperial Sizing Wax on the exterior of the case (smaered on with fingers) and inside the neck (applied with a cotton swab). I'm sure many will find fault with this approach, but it works for me.

Thanks for the long dissertation on what you have found works for you. I must have somehow missed your answer to the initial post.

 

[Firearmsunlimited]

Let your rifle tell you what it likes best, .001 or .002

Brilliant! - thanks

 

[Alex Wheeler]

Neck tension is part of the tuning process, unfortunately no one can tell you what your barrel will want just like they cant tell you what powder charge or seating depth. You will have to test them.

 

[Dave M.]

Not that seating depth in relationship to the lands has anything to do with neck tension but +.005.
Mid pressure loads
Bolt action
Feeding single rounds
In the past I have found that .003 is the breakover point that starts to negatively impact accuracy with the exception of VLD's.

You need to do more testing then because the break over point certainly isn’t 0.003” neck tension. I think you may be surprised what you find in the .005”+ range

 

[garandman]

What is this designation... .001 or .002 for neck tension?

 

[JFrank]

What is this designation... .001 or .002 for neck tension?

Bushing talk..... .001 or .002 under a loaded round OD, as mentioned above experimenting with different size bushings. is part of the tuning process, each incremental change will yield different results especially apparent at long range.

 

[Chiquita]

Similar to what has been said above.

Start a group with .001 and work it up. Or start high .004 and work down.

Shoot 5 or 10 shot groups with each tension with a chronograph and document results.

My 1.5 cent.

 

[INTJ]

With a .224 bullet and brass with .014 necks would you use .001 or .002 neck tension? Brass is new and I re-anneal after every 5 firings so spring back isn't a real concern.
Thanks

Annealing after every five firings is probably not optimal. You have small changes in brass hardness and spring back in firings 1-5, then a big change after annealing for firing number 6. With that in mind, it seems best to either not anneal at all or anneal every time. That keeps the changes between firings minimal.

Regardless of all that, I agree with others here that testing varying neck tension is a way to fine tune loads. I generally find that too little neck tension is much worse than too much. I am not sure at what amount of neck tension this happens, but somewhere after .004" or so the brass starts yielding so going much over that often counterproductive. I expect neck thickness is what determines how much neck tension we can get before the brass yields. Again, the only way to know is to try it.

 

[Ned Ludd]

In loads with heavy (90+ gr) .224 bullets for an F-TR bolt rifle, I have always started load development at ~.002" neck tension/interference fit. Although I have occasionally tested within the 0.001" to 0.003" range, I have never had reason to change loads over from the initial .002" neck tension. I also anneal after every firing. In my hands, .002" neck tension works well enough that the loads are never the limiting factor in terms of precision (i.e. the nut behind the rifle is the limiting factor). Nonetheless, it's a simple enough exercise to prep a small number of cases with different bushings and/or mandrels sufficient to load up a few rounds, and then determine empirically which shoots optimally.

 

[Firearmsunlimited]

Need to clairify. I mis-labeled the thread and was not clear on what I am asking. My question intended to relate to shoulder bump not neck tension.

 

[JFrank]

Need to clairify. I mis-labeled the thread and was not clear on what I am asking. My question intended to relate to shoulder bump not neck tension.

Nice redirect..
Here's another

 

[ronemus]

Need to clairify. I mis-labeled the thread and was not clear on what I am asking. My question intended to relate to shoulder bump not neck tension.

0,001" is sufficient, but there is some variation so 0.002" is safer (good technique will hold variation to 0.001" or so); there should be no downside to bumping 0.002".

 

[klamathsteel]

A little off topic but what the Hell ever became of Fguffy ? Googy as he was ?

 

[mgunderson]

As shooters we all reason and apply logic to our process and what we have experienced. The best advice is to try it. Something in the 0.001 to 0.005 inch will work. It may not work for the reason we think and it may not work in every situation and with every powder. There are some very complex interactions with bullet retention and combustion. I am not able to explain how it all works together..... so I test and learn.