Where does neck tension fit in?

[Lenard]

Assuming you are loading accurate ammo, I am curious how neck tensions fit into the list of important features of "to do's".

I had some test loads that were loaded three days before I fired the majority of them. The loads that did not meet my criteria, I pulled the bullets on. Some slipped right out and others took much more pressure. It got me to thinking that there was a wide deviation between neck tension in some of my loads.

 

[mikecr]

I think it's important enough to establish(as stable) even before load development.
It's difficult to pick through a shotgun pattern ladder to determine best charge, and bad chosen seating depth and variance in neck tension can lead to this regardless of charge.

So my initial annealing is before fireforming of new cases, and I also determine best seating(coarse) while fireforming. Once my cases are stable across the board(2-3 firings), I ladder test. This is a condition I maintain as my load is affected by it.
I don't trust factory anneal, nor the DIY flame spinners as that is no better than factory. I lead dip.

You can maintain tension through an annealing schedule, or a minimal sizing plan. Otherwise, it's too difficult really(separating schemes).
You can maintain seating depth through diligent measure of each every time.

 

[amamnn]

Just to put it in perspective for the casual shooters:

It is something that should be uniform in all cases, as far as you can make it. Its importance in the grand scheme of things will depend upon the quality of the rifle in which the round is to be fired and the skill of the shooter.

When some slight differences exist it is not going to make a big difference (if any) in accuracy when the shooter is not skilled, the platform is not stable, the rifle is built to standards that allow a lot of slop in the action and barrel and no wind doping methods are used.

 

[artbosco]

Assuming you are loading accurate ammo, I am curious how neck tensions fit into the list of important features of "to do's".

I had some test loads that were loaded three days before I fired the majority of them. The loads that did not meet my criteria, I pulled the bullets on. Some slipped right out and others took much more pressure. It got me to thinking that there was a wide deviation between neck tension in some of my loads.

Neck tension is a very important part of the Tuning process if you're concerned with accuracy.

Once you've found your load: the right barrel, bullet, powder, case, and primer combination, you fine tune with seating depth and neck tension [using for example, a Full Length Type-S/Harrell's Bushing Die, with an assortment of bushing, .001", .002", .003", .004" under your loaded round's Outside Diameter].

I've seen 5-shot tight cloverleaf groups go to one-hole groups with as little as .001" of tension applied between the assortment. To carry that a little further, I've seen the same change take place with as little as .001" of seating depth too. Sometimes in combination.

 

[1shot]

MIKECR,
Just so that I get this straight in my head. you say that factory annealing isn't good enough, so I should re-anneal my new Lapua brass before I even load them to fire form the brass? Inquiring minds want to know.
Lloyd

 

[Marksman]

To piggy-back on this thread; where should you start your tension at when working up a load?

 

[Chappy]

To piggy-back on this thread; where should you start your tension at when working up a load?

I've always started at 0.002" of tension. Then once I get the best load I can through various charges and primers and seating depths, that's when I mess with NT. Load 10 up at 0.001", 0.002", 0.003" 0.004", and 0.005". Always have found the sweet spot between 0.0015" and 0.003". YMMV.

 

[BenPerfected]

To piggy-back on this thread; where should you start your tension at when working up a load?

I've always started at 0.002" of tension. Then once I get the best load I can through various charges and primers and seating depths, that's when I mess with NT. Load 10 up at 0.001", 0.002", 0.003" 0.004", and 0.005". Always have found the sweet spot between 0.0015" and 0.003". YMMV.

Once you have your load dialed-in and found the best neck tension for this round, do you consistently maintain the same neck tension for this load? Do the number for times the brass is fired impact the neck tension?

 

[Chappy]

To piggy-back on this thread; where should you start your tension at when working up a load?

I've always started at 0.002" of tension. Then once I get the best load I can through various charges and primers and seating depths, that's when I mess with NT. Load 10 up at 0.001", 0.002", 0.003" 0.004", and 0.005". Always have found the sweet spot between 0.0015" and 0.003". YMMV.

Once you have your load dialed-in and found the best neck tension for this round, do you consistently maintain the same neck tension for this load? Do the number for times the brass is fired impact the neck tension?

I think it depends. If you don't turn your brass, I suppose you could say that it might affect tension. But I turn my brass and aneal every 4 firings. I haven't noticed anything to date but I'm just an F/TR shooter, not a BR shooter!

 

[fguffey]

I've always started at 0.002" of tension.

I can not measure tension in thousandths, I can measure interference fit. When measuring the necks ability to hold the bullet I can measure bullet hold in pounds. There is a 'new tool', it measures bullet seating in pounds , I guess the next 'new' tool will convert pounds to tensions.

New tool? I have hand seating dies, most are at least 50 years old, then there is determining bullet seating effort in pounds, again, nothing new. Place the case on a scale, place the seating die on the case and then seat the bullet while reading the scale.

I want all the bullet hold I can get.

F. Guffey

 

[markm87]

When I've compared virgin Lapua .308 brass, and RWS 300WM brass (both of which can have pretty hearty neck tension based on the feel from the press and arbor press respectively) against previously fired, mild neck tension brass, I've not been able to note any differences in velocity or accuracy.

Conversely, when I don't put a light crimp on my 223 OTM bulk target load, my group size more than doubles. I suspect that has to do with the crimp equalizing neck tension with mixed brass.

 

[mikecr]

you say that factory annealing isn't good enough, so I should re-anneal my new Lapua brass before I even load them to fire form the brass?

This is my opinion and what I do, yes.
I'm not going to hang a hat on results of MY load development while a bunch of variables exist. That is, variables I could remove myself through prior preps, testing, and fire forming.

I have no faith in case process annealing until lead dipped. No faith in case weight, until validated with H20 measure. No faith in primer seating without measure of seated crush. Measure of sizing, flash holes, ogive radius, CBTO, seating force, charging, MVs, etc..

 

[Joe R]

Lenard said:
Assuming you are loading accurate ammo, I am curious how neck tensions fit into the list of important features of "to do's".

I had some test loads that were loaded three days before I fired the majority of them. The loads that did not meet my criteria, I pulled the bullets on. Some slipped right out and others took much more pressure. It got me to thinking that there was a wide deviation between neck tension in some of my loads.

Welcome to AS Lenard,
Most of the people hanging around here are shooting at what I would call extreme range, 1K yards. Some have been at it for decades and continue to learn while teaching many newbies like me and you. So you're going to get responses that may seems hard to comprehend. It would be easier for guys to help you if you first describe the rifle you're shooting and what your objectives are, otherwise it'll be very difficult for anyone to hit the mark if they don't know what your objectives are.

Kindest regards,

Joe

 

[Lenard]

Thanks for the information everyone. For me this evolution of shooting a 1/2" gun has been rather uneventful. I shoot two particular guns, a sporter weight 20 TAC mini mauser and another sporter weight Sako 223 with PacNor barrels. My main targets are Rock Chucks shot in Oregon. And, this last spring/summer, my two partners and I shot 400 of them. We are somewhat limited by terrain to shooting 400 yards. And by the way, my other hobby is making troubled guns shoot better. Been doing it for years.

I have learned much by reading this site over several years. On a good day, my two guns easily shoot under 1/2" and many times reaching the .100-.200 group size.

I am constantly attempting to do away with fliers. I have conquered the run out on loaded ammo, but still occasionally get fliers which I am attributing to neck thickness. I shoot LC cases as I have found them to be much more consistant than any of the commercial cases made by american gun companies. The trio of us are in our 70's and constantly work to improve on our ammunition we reload.

Thanks again.

 

[mikecr]

When I consider fliers, I consider the following:
Excellent scope
Excellent trigger pull
Best/consistent seating depth
Best/consistent neck tension
Cases matched in H20 capacity
Best primer striking

 

[M14AMU]

Neck tension is synonymous with ULTRA ACCURACY!!

 

[jlow]

You still got to be in your node regardless of how good your new tension is. When I see a flier, I always blame being out of the node and the darn barrel flinging my bullets... ;D

 

[mikecr]

It hurts to consider flingers (flyers are bad enough)

 

[jlow]

Flyers are flingers! I like it this way because I can then blame the barrel! ;D

 

[joshb]

Sorry to jump in and hi-jack, but I read one member's reference to "lead dip annealing". That sounds very interesting. How is it done?