Neck Tension & Group

[Coolhand]

I have a load that is working very well but tends to want to string vertically.I have to seat to mag length, I was wondering if an increase or decrease in neck tension will affect the group size and shape. I have just started using a Neck Bush die and still learning about them.
The load I am using is not far off redlining and I don't want to push it any further.
45.8 grains of RL17 groups are open and average around 1.25''
46 grains no real change.
46.2 grains group tightens up.
46.4 is the money but tends to want to run vertical.

appreciate the advice.

Mike.

 

[skiutah02]

It has been my experience, limited in duration but made up for in volume I like to think, that consistent neck tension is as (and sometimes more) important as seating depth and powder charge (caliber dependent).

In short, changing neck tension does often effect group size and small inconsistencies can have big effects.

Drew

 

[Nude nut]

I have a load that is working very well but tends to want to string vertically.I have to seat to mag length, I was wondering if an increase or decrease in neck tension will affect the group size and shape. I have just started using a Neck Bush die and still learning about them.
The load I am using is not far off redlining and I don't want to push it any further.
45.8 grains of RL17 groups are open and average around 1.25''
46 grains no real change.
46.2 grains group tightens up.
46.4 is the money but tends to want to run vertical.

appreciate the advice.

Mike.

Hi,
I have found correct neck tension will close up groups but in general inconsistant neck tension will throw fliers out side the group.
Without knowing your rifle handling skills there is other factors that will cause vertical in a group different hold different cheek pressure even rear bag soft/hard and more.
Have also found different primers can get rid of vertical as adiusting powder charge.
How are you using your bushing die are you usuing sizing button and do you neck turn,
If you dont neck turn polish your sizing button and use a bushing that allows the sizing button to just glde through the neck myself I size neck down then run a neck turning expander through the neck in a expander die works for me.

Cheers Trev.

 

[Joe Salt]

Coolhand if you are seating to mag length, how far of the lands are you? And what bullet are you using? You maybe be able to seat a little shorter.

Joe Salt

 

[Shynloco]

Coolhand,
In a short answer, YES neck tensions will affect your grouping. I'd be curious as to what the rifle is you are shooting. And I'd also ask if you have noticed any pressure signs as you increase your load (i.e cupping on the primers). Even changing primers could affect your grouping, which is something you may want to consider once you've found your best load, considering the restrictions you may have with having to load from a magazine. But remember, only change ONE aspect of your load at a time so you'll know what specific change works best in your particular rifle.

Alex

 

[DOGCAPPER]

Do you notice a difference in neck tension as you are seating bullets? If so sort them out as you load.. Then compare tight vs. looser for group.
Some of my club members use the Sinclare seating indicator.










d

 

[savagedasher]

Do you notice a difference in neck tension as you are seating bullets? If so sort them out as you load.. Then compare tight vs. looser for group.
Some of my club members use the Sinclare seating indicator.

When you seat a bullet your expanding the neck .
The amount of pushing resist it takes to do it can very . Things I see Finish surface and Angle and amount case bevel resistance to stretching of the brass defiantly the angle of the bullet when seating starts. I like the double tap method Start the seating process back off rotate the case and finish seating . Larry








d

 

[4xforfun]

As a side note.... I have found that once you find the proper neck tension, you are done testing in that chamber. I used to test whenever I switched bullets, and ALWAYS ended up using the same bushing. Now, if I happen to switch bullets for some reason, I don't need to test neck tension.

Just my .02,
Tos

 

[500Stroker]

Hi,
I have found correct neck tension will close up groups but in general inconsistant neck tension will throw fliers out side the group.
Without knowing your rifle handling skills there is other factors that will cause vertical in a group different hold different cheek pressure even rear bag soft/hard and more.
Have also found different primers can get rid of vertical as adiusting powder charge.
How are you using your bushing die are you usuing sizing button and do you neck turn,
If you dont neck turn polish your sizing button and use a bushing that allows the sizing button to just glde through the neck myself I size neck down then run a neck turning expander through the neck in a expander die works for me.

Cheers Trev.

Just curious, what do you consider the "correct neck tension" to be? And how are you measuring it?

 

[savagedasher]

I pay no attention to seating depth or tension . Seating depths I use to lower Es and Sd .Then I grab the Tuner . Larry

 

[dmoran]

I pay no attention to seating depth or tension . Seating depths I use to lower Es and Sd .Then I grab the Tuner . Larry

Larry
In your first sentence you say you "pay no attention to seating depth".
Then in the next sentence you say you do "use it to lower ES/SD".
Your contradicting yourself. What gives?

My experience is tune the load all you can (neck tension included), then go at the tuner if you have one.
Donovan

 

[savagedasher]

Larry
In your first sentence you say you "pay no attention to seating depth".
Then in the next sentence you say you do "use it to lower ES/SD".
Your contradicting yourself. What gives?

My experience is tune the load all you can (neck tension included), then go at the tuner if you have one.
Donovan

No that is your way. I check the case capicity Then I drop the powder knowing I'm going to jump the bullet .020 plus. That is the only known point . Keep pushing it in till I get lowest Es . Using the dial on the seater . Go a couple number each way . Then I seat them that length and adjust the tuner . That seating stem is for that gun. When my Es change I change the seating depth and the tuner . Rim fire has done it for years . Why would I want to reinvent the wheel .?
Larry

 

[Coolhand]

Gents, appreciate the replies.... I have a .220 AI.The Neck die is a Newlon which was cut with the same reamer that did the chamber. The Newlon die does not have an expander ball, the seater die is also a Newlon. I use a Universal decapping die to de prime.
I don't know how far I am off the lands and at present the 52 grain Berger FB Varms are seated to a full calibre. I can go to half a calibre and still clear the mag but not a lot of neck gripping the bullet which is not so bad as the Bergers are flat base. I also shoot 55 gr Sierra Blitzkings so with the BT even less neck grip.
I have not encountered any pressure signs but I don't want to push it any further. I am using QL as a guide and QL says I still have approx another 3 grains to go but the pressure figures are right up there, I would like to stay out of the PINK zone!
So far I have only found a couple of cases that 'feel' loose when seating bullets, Norma cases btw.

Loaded round measures .253" so I started with a .251" neck bush. My thought was to load identical rounds and just vary the neck tension, with the original .251" bush and then go down to a .250" and maybe go up to a .252"

regards
Mike

 

[Nude nut]

Just curious, what do you consider the "correct neck tension" to be? And how are you measuring it?

I start 1 thou less than a loaded round and experiment from there as my circumstances are different to yours as I read your first post your using a magazine you would want to be using 2 to 3 thou smaller bushing than your loaded round.
Do you anneal your brass or neckturn as I dont neckturn as yet I polish necks dip them in graphite and run the expander through the necks to even out the inside of the neck after sizing the neck down a tad smaller than my expander mandrel this gives me consistant seating pressure.
Other option would be to neckturn even a skim over the necks and regular annealing as far as what is the correct tension experimenting will tell you but from my own experience if seating with jump firm seating wins for me seating into the lands soft seating wins for me.

Cheers Trev

 

[500Stroker]

I start 1 thou less than a loaded round and experiment from there as my circumstances are different to yours as I read your first post your using a magazine you would want to be using 2 to 3 thou smaller bushing than your loaded round.
Do you anneal your brass or neckturn as I dont neckturn as yet I polish necks dip them in graphite and run the expander through the necks to even out the inside of the neck after sizing the neck down a tad smaller than my expander mandrel this gives me consistant seating pressure.
Other option would be to neckturn even a skim over the necks and regular annealing as far as what is the correct tension experimenting will tell you but from my own experience if seating with jump firm seating wins for me seating into the lands soft seating wins for me.

Cheers Trev

Coolhand started this thread, I just jumped in on "neck tension".
I am a bench shooter 600 yards, I load for my 6 Dasher and a 6BRX.
I load for the lightest tension possible and jump the bullet .010 of the lands, it appears to be working, but I am always looking for new ways to improve. Thanks for the info, good luck down under.

 

[Nude nut]

Coolhand started this thread, I just jumped in on "neck tension".
I am a bench shooter 600 yards, I load for my 6 Dasher and a 6BRX.
I load for the lightest tension possible and jump the bullet .010 of the lands, it appears to be working, but I am always looking for new ways to improve. Thanks for the info, good luck down under.

Sorry about that didnt catch that,
I also tried light neck tension with jump but found my case necks and shoulder and chamber gets more powder fouling and velocity drop I guess that would be dependent on chamber specs.
Myself I load 10 thou in with 1thou nk tension gives me cleaner neck, shoulder,chamber and more velocity so when jumpping bullets I go 2 to 3 thou neck tension seems to give similar results.
I shoot 308 and 6.5x47 and 223 I load them all the same way I shoot fclass rear bag and joypod no benchrest in my neck of the woods.

Cheers Trev.

 

[Coolhand]

Well I bought some more bushes to vary my neck tension. I asked my engineer buddy to gauge the bushes , oddly both were .001" under the size stamped on the bush.
The .252 went .251, the .250 was .249 and an older bush I had which is marked .248 is .247 !

Is this common with Redding Tite Nitride bushes ?

Mike.

 

[Nude nut]

Well I bought some more bushes to vary my neck tension. I asked my engineer buddy to gauge the bushes , oddly both were .001" under the size stamped on the bush.
The .252 went .251, the .250 was .249 and an older bush I had which is marked .248 is .247 !

Is this common with Redding Tite Nitride bushes ?

Mike.

Yes hear it mentioned many a time havnt measured any myself I just play until I find one that works.

Cheers Trev.

 

[WyleWD]

Gents, appreciate the replies.... I have a .220 AI.The Neck die is a Newlon which was cut with the same reamer that did the chamber. The Newlon die does not have an expander ball, the seater die is also a Newlon. I use a Universal decapping die to de prime.
I don't know how far I am off the lands and at present the 52 grain Berger FB Varms are seated to a full calibre. I can go to half a calibre and still clear the mag but not a lot of neck gripping the bullet which is not so bad as the Bergers are flat base. I also shoot 55 gr Sierra Blitzkings so with the BT even less neck grip.
I have not encountered any pressure signs but I don't want to push it any further. I am using QL as a guide and QL says I still have approx another 3 grains to go but the pressure figures are right up there, I would like to stay out of the PINK zone!
So far I have only found a couple of cases that 'feel' loose when seating bullets, Norma cases btw.

Loaded round measures .253" so I started with a .251" neck bush. My thought was to load identical rounds and just vary the neck tension, with the original .251" bush and then go down to a .250" and maybe go up to a .252"

regards
Mike

I take it that this is a 220 Swift AI.(?)
My curiousity is how you selected R17 as your candidate for powder? Strictly by QL or did you try other powders before settling on this one?

I've been casually (low priority) trying to get R17 to work in my Swift with 50, 52, and 55gr bullets off and on for 3 years and what I encounter is just about what you are seeing in the way of groups. Blinding speed, but unstable groups at this point. WD

 

[Fotheringill]

I have read about the size difference here that Redding is undersized from what is stamped. There was another company mentioned that has steel bushings only. I got a few for my .223. I don't have the equipment to actually measure the bushings but the new ones have a slightly easier pull on the ram when sizing.