Neck tension

[grantre72]

So... I will tell you that some top benchrest 1000 yard shooters use up to .005 neck interference in their 6mm rounds without annealing. I can also tell you that a member of the FTR USA Shooting Team uses .005 neck interference in his .308 rounds.

I have run up to .005 neck interference in my 6BRA F-Class rifle.

Neck interference and neck tension are NOT the same thing. .002 neck interference on a .015 thick neck wall does not give the same neck tension as .002 interference on that same neck that has been turned down to .011. Softer brass gives less neck tension than harder or work hardened brass using the same sizing bushing.

Don't let anyone tell you what is right or too much because most of them have never tested at distance. Brass manufacturer, annealing vs not annealing, neck turning vs not neck turning, neck thickness, powder, primers, and I'm sure a lot of other variables affect what your neck tension actually is and what your rifle likes.

Test neck interference in your rifle at the maximum distance you will be shooting to see what provides YOU the smallest groups in YOUR rifle. That's where you will find the right answer.

Agree. My smith is a several times benchrest winner. He seats his 6PPC to .004-.006" interference.

 

[jepp2]

SAYING 4 THOU without any other info is like saying is a 1000 feet high enough.
what gun
what cartridge
what bullet weight
what type of shooting
single fed or mag fed ???
just to start

To continue,
- do you anneal and if so how often?
- how do you clean your brass?

If you leave the carbon from firing in the case neck vs removing it, makes a difference. Same with annealing. At 0.004" neck tension you are basically using your bullet as an expander, but test and see what works on the target given your specifics.

 

[Dave M.]

4 thou is way to much in a bolt gun, but i have no faith in a 22cm so oh well

4 thou is a lot of neck “tension”, but by no means is it “way too much”.

 

[Dave M.]

What I know is initially I was using a 226 bushing in my S die, with no neck turned LC brass made to 20 Practical. 226 was not enough to hold the bullet in place. I then tested the 225 and it consistently held it. 224 I thought was overkill, so I have used the 225 since then. I don't have good enough calipers to measure exactly how many thousands it is. Hope that helps.

Calipers are not the right tool for that job. Tube mics are.

 

[762plinker]

Calipers are not the right tool for that job. Tube mics are.

not a tube mic, measure the bullet dis with a 0-1 mic (.0001) and then set a bullet. measure the dia of the loaded neck, do the reverse math for "tension" or case neck thickness

 

[Dave M.]

not a tube mic, measure the bullet dis with a 0-1 mic (.0001) and then set a bullet. measure the dia of the loaded neck, do the reverse math for "tension" or case neck thickness

Sorry I said tube mic but I meant mics. This is exactly how I do it as well.

 

[Ruger15151]

the most accurate way to measure the ID of your necks is with Pin gauges. You can buy them in .0005 increments for about $4 if you google. Sometimes you can also buy them on Amazon.

 

[INTJ]

Is 4 thousands too much ?

Absolutely not. Some of my best shooting LRBR rifle loads have .004" of neck tension. Much more than .004 to .005" doesn't really increase bullet hold because at some point the brass just yields.


Generally, a little too much neck tension isn't an issue. However, to little neck tension can cause consistency problems.

 

[Kracken McGraw]

Much more than .004 to .005" doesn't really increase bullet hold because at some point the brass just yields.

Thanks for saying that. This was my rationale on it too.

 

[Mark611]

Have you ever tried to pull a bullet with a kinetic hammer? with 3k neck tension it takes several heavy blows on a block of wood to knock a bullet out of the case, IMO unless you're shooting some kind of heavy recoiling magnum? IMO 3k is more than enough.

 

[kochie]

Absolutely not. Some of my best shooting LRBR rifle loads have .004" of neck tension. Much more than .004 to .005" doesn't really increase bullet hold because at some point the brass just yields.


Generally, a little too much neck tension isn't an issue. However, to little neck tension can cause consistency problems.

Thank you sir good info

 

[Mulligan]

Absolutely not. Some of my best shooting LRBR rifle loads have .004" of neck tension. Much more than .004 to .005" doesn't really increase bullet hold because at some point the brass just yields.


Generally, a little too much neck tension isn't an issue. However, to little neck tension can cause consistency problems.

Folks^^^^^this is GOLD^^^^^ take it to the bank!

In my bolt guns, I test it, period!
Some powders show a preference for more grip/tension. You don’t know until YOU test it in YOUR rifle.
CW

 

[Alex Wheeler]

Yep, same answer to 90% of load questions. Only the target has the answer.

 

[Ccrider]

Have you ever tried to pull a bullet with a kinetic hammer? with 3k neck tension it takes several heavy blows on a block of wood to knock a bullet out of the case, IMO unless you're shooting some kind of heavy recoiling magnum? IMO 3k is more than enough.

I am still new to all of this, but tell me, what, exactly, are you basing your statement that 3k is more than enough on?

 

[nakneker]

Test it, one answer does not fit all semi auto, all bolts, all cartridges. In some rifles neck tension makes a big difference on the target then I use to think, the only way to know is test it. I didn’t do that for a very long time, never gave it much consideration. When I did try different neck tensions I was amazed at the difference it made on some of my rifles. I still don’t test it much unless I’m having issues with groups or SD and ES numbers, if I am having issues it’s one of the first things I look at. I typically keep .002 on my bolts, .003 on my levers and .004 on the ARs.

 

[Mark611]

I base this from using the Lee collet die, I use them for all the calibers I load, 308win bolt and semiauto M1A rifles, also loading for 223/5.56 in bolt and semiauto AR rifles, all of my AR 6.5Grendle rifles, {etc} I do not crimp my bolt guns, my AR's in 223wylde whether I'm using 223rem cases or 5.56 cases or my 6.5GRR cases I have factory crimp dies, but they only put very little pressure on the case mouth, they just kiss the case no real pressure on the crimps, and believe me it takes a lot of hits to drive a bullet back out of the case, and I get excellent accuracy using this method using the right powders and bullets the barrels like, YMMV

 

[Ccrider]

A

I base this from using the Lee collet die, I use them for all the calibers I load, 308win bolt and semiauto M1A rifles, also loading for 223/5.56 in bolt and semiauto AR rifles, all of my AR 6.5Grendle rifles, {etc} I do not crimp my bolt guns, my AR's in 223wylde whether I'm using 223rem cases or 5.56 cases or my 6.5GRR cases I have factory crimp dies, but they only put very little pressure on the case mouth, they just kiss the case no real pressure on the crimps, and believe me it takes a lot of hits to drive a bullet back out of the case, and I get excellent accuracy using this method using the right powders and bullets the barrels like, YMMV

Thanks for explaining. We are on two different planets.