I KNOW it absolutely matters if you are trying to shoot little groups in a gun that’s capable of that, I normally find that .001-.003 is where I end up.
Does Neck Tension matter ?
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GeoDudeFlorida
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Let’s keep in mind the topic question: Does neck tension matter? It’s not specific to tight or loose. Nor is the question about degrees of tight or loose. Just, does it matter?
I can think of a few - but only very few - situations where the tension of the case neck on the bullet shank is irrelevant, or nearly so. A hand fed cartridge where the chamber is very tight and the bullet is meant to just touch the lead is one. The case neck has to fit the chamber so by default the bullet will not be flopping around in the neck. We’re going to assume the shooter is trying to hit an intended target, not create a failure to fire.
The method of finding “jam” but with a live round is what I tried - on the advice of a more experienced shooter - and without the splits some people cut into their cases.
It was an interesting experience and one of the first strange things I tried with a Contender .30-30.
I can think of a few - but only very few - situations where the tension of the case neck on the bullet shank is irrelevant, or nearly so. A hand fed cartridge where the chamber is very tight and the bullet is meant to just touch the lead is one. The case neck has to fit the chamber so by default the bullet will not be flopping around in the neck. We’re going to assume the shooter is trying to hit an intended target, not create a failure to fire.
The method of finding “jam” but with a live round is what I tried - on the advice of a more experienced shooter - and without the splits some people cut into their cases.
It was an interesting experience and one of the first strange things I tried with a Contender .30-30.
I think different levels of neck tension certainly matter. But Ill be honest, I set my neck tension at 2 thou and just call it good for everything I shoot. Im lazy like that, and Im happy with guns that shoot a consistent 1/2 minute.
I think the thing that matters more than anything is consistent neck tension. And that is obtained by annealing or by using ever tighter bushings. Personally I think annealing is a simpler solution.
I think the thing that matters more than anything is consistent neck tension. And that is obtained by annealing or by using ever tighter bushings. Personally I think annealing is a simpler solution.
kmw1954
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Well as some of our members know I load to shoot in a local rifle league with a 223REM. I learned the very first year of shooting that at least in my rifle for what I am trying to do it does matter. When I first started chronoing my loads I found that my ES was all over the place. I was finally narrowed down by friends at the range and members here that my neck tension was also all over the place. I worked on that one issue and the ES and my group size improved.
It depends. Single shot rifle, you probably want to use a minimum of neck tension and seat the bullet until it just touches the rifling. A lever action rifle on the other hand will benefit from a firm crimp and most of them will demand a specific OAL.
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I can have consistency along plenty of neck tension just by consistent prep work, myself I leave the carbon in the neck and simply brush the neck insides with a nylon brush which reduces seating friction. I can run .004 neck tension with smooth modest seating force. Im not certain you could maintain. .004 neck tension while annealing ?
I don't approach neck tension with bushings. I use mandrels. It's just a simpler system for me. I don't see any reason you couldn't have 4 thou with a mandrel either. Just use a 4 thou undersized one. I just go 2 thou because those are what I own, and seem to work well in my guns.
The same can be said for bushings. But instead of having to use smaller bushings as the brass work hardens and springs back more, annealing would allow you to just use the same bushing effectively forever. I've personally seen cases with 5-6 firings on them that spring back post sizing so much bullets will fall into the case. The only way to get that tension back is to use a smaller bushing, or remove the spring back caused by work hardening via annealing.
I wet tumble, so my carbon is gone, so I use Imperial dry neck lube before I mandrel, and brush with a nylon brush. It's resulted in really consistent feeling seating for me.
There is like 15 ways to skin a cat, I'm just putting my method out there, which works pretty well for me. I think we can all agree on one thing though, consistency is key.
Varminterror
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His point is that he doesn’t believe annealed brass would be strong enough to squeeze 4 thou after the bullet is inserted. Rather he expects the brass will be too malleable and will expand to match the bullet diameter with less resulting grip.
Personally, I’ve not had trouble annealing and producing 4 thou bullet grip with several cartridges, but I don’t typically use so much, but I have also seen that not all brands of brass nor all calibers of cartridges respond the same.
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I have nothing against mandrels, I don’t always see them .004 and .005 under my bullet size. I may adopt the method one day ~ if I tested and found improvement I certainly would.
I see where he is coming from now!
Yeah, I honestly dont know, but I would suspect that it might give slightly, and I would say ever so slightly less grip, on the bullet. Thats just a WAG though.
Varminterror
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It does give, a lot.
When you’re trying to hold 4 thou neck tension with annealed brass, it often means we need to be 6-7thou undersized so the brass can grow around the bullet but still hang on to 3-4 thou, but some brands will buckle at the shoulder when we try seating into 6-7 thou undersized necks.
jmorris
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It depends. The answer can be absolutely or not at all and even somewhere in the middle.
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I’m told by many people with far more experience than myself that different caliber and powder combinations seem to have preferences. I can only speak on the ones I own and shoot but they’re all different.
21st Century and K&M both make 4 or 5 thou mandrels Im fairly certain.
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This is the set 21st century offers, minimum size is only.003 ( actually .0025 ) under bullet diameter. I already own several mandrels just none the size I would require for this caliber.
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jmorris
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I find it easiest, if things seem to not matter, to go to each end the spectrum.
If you took a straight wall case with a primer in it and put it into a single shot and loaded it from the muzzle with a ball and patch with BP, its not going to make any difference, as it doesn't even really need to be there except for the primer. If you have a 25 acp case that shoves the bullet in and extra 1/4" upon chambering, the results could be catastrophic as pressures rise above the maximum, designs are capable to withstand.
jmorris
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Add that to the list of why a lathe is a nice tool to have. Any size out of any material you can get your hands on.
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I doubt id buy a lathe just to turn down a mandrel when I have a selection of $12 neck bushings. Testing a bit is the best way to determine the optimum amount of bullet hold one’s particular rifle prefers, when in doubt I start with plenty. Guys that don’t test either don’t have the tools, dont care of don’t know how to proceed. I think in the first post I covered the way I go about it. I’d like to hear how others go about testing.
AmenM1 Garand - neck tension is very important
T/C Contender - neck tension is almost irrelevant.
I proved it to myself before a lot of members of this board were born. Now y’all go out and prove - or disprove- it for yourselves.
Only experiments I've done is simple in my world. Size , check with ball gauge , press bullet , pull bullet , check with ball gauge. Neck softness totally matters. The resulting measurements makes me look sideways at some of these comments. But so does shoulder bumping measurements. It's more of an average of many than rule of a few samples. Sample size matters. Now I'll not butt in on long distance precision . That's psychological as well as voodoo as well as mechanical. TGIF
GeoDudeFlorida
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I think it’s interesting to note how many people believe it doesn’t matter but don’t show how they arrive at that conclusion.
Testing stuff isn’t difficult and usually worth a bit of time to learn something.
I’ll throw out a couple methods;
A guy could remove the expander system and size 12 cases then using 4 different size mandrels neck up 3 of each size. Now shoot those in a horizontal foremat at 4 seperate bull eyes at the longest range available.
How about the same thing yet color the tips with different color sharpies and shoot them in a round robin foremat at 300 or 400 yards using one bullseye/one point of aim and just note how they group.
There are other ways for those that like to test stuff and learn something about their firearm.
Any more testers out there that want to share ?
There may be a lot of guys that want to test stuff that are not sure how to go about it for best results.
Testing stuff isn’t difficult and usually worth a bit of time to learn something.
I’ll throw out a couple methods;
A guy could remove the expander system and size 12 cases then using 4 different size mandrels neck up 3 of each size. Now shoot those in a horizontal foremat at 4 seperate bull eyes at the longest range available.
How about the same thing yet color the tips with different color sharpies and shoot them in a round robin foremat at 300 or 400 yards using one bullseye/one point of aim and just note how they group.
There are other ways for those that like to test stuff and learn something about their firearm.
Any more testers out there that want to share ?
There may be a lot of guys that want to test stuff that are not sure how to go about it for best results.
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OP
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When I did anneal, I used the torch method and didn’t like it at all. A friend of mine uses the Amp system to anneal his 6 bra brass and found that he could not get .004 -.005 under to hold, so he quit annealing that brass and after work hardening a bit they responded favorably to the extra hold. As you point out not all cartridges like more hold. I completely agree.. that’s why I test.
Nature Boy
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In my mind load development is a process of isolating variables and removing them from the equation in sequential order once a favorable result has been achieved.
As it relates to neck tension, I choose not to introduce it as a variable, preferring instead to lock it down as a constant 0.002” and twist other knobs in the process (i.e. powder charge, seating depth, primer selection and barrel tuner).
I have no doubt it has an effect but I’m basically tuning around it instead of adding it as another control knob.
Finite time, finite components. I have to draw the line somewhere
As it relates to neck tension, I choose not to introduce it as a variable, preferring instead to lock it down as a constant 0.002” and twist other knobs in the process (i.e. powder charge, seating depth, primer selection and barrel tuner).
I have no doubt it has an effect but I’m basically tuning around it instead of adding it as another control knob.
Finite time, finite components. I have to draw the line somewhere
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