Neck tension results

[Elwood]

This was done earlier on in the year, I have only just got round to putting this up.

 

The loads are identical in every single way, except for neck tension. They were all shot on the same morning so conditions were also identical.The scope wasn't adjusted and the aiming point for all three targets was the X ring.

 

I was trying to get my extreme spread down below 20 and neck tension was the last roll of the dice.

 

This is using 1 thou neck tension.

 

 

using 2 thou neck tension

 

 

and 3 thou neck tension.

[Ronin]

Is that the old barrel Ian ?

 

If so are the results the same with the new barrel - I am also running .003" tension but speeds are a bit higher.

 

I have .004 overall clearance on loaded round too (.002" all around)

 

also is there a difference with annealed and non annealed cases?

 

My quest - like yours is ultimate accuracy with the seven

[Elwood]

Looking at the velocity and powder charge that would have to be with the old barrel Andy. As the same reamer was used on the new barrel I chose to use the information that I had already acquired and ran with the 3 thou neck tension.

 

Interesting question regarding if there's any difference between new annealed brass and old, maybe I will experiment when the new barrel is shagged out (excuse the technological terms)

[sporting rifles]

I found changing to a std match primer instead of the magnum primer tightens the groups I did this in my 7mm wsm and my mates 270 wsm

[Ronin]

I haven't tried anything other than match primers in my own 7 both Fed and CCI give same groups and similar velocities.

 

 

I did try using some Winchester cases a while ago whilst doing load dev (as opposed to Norma)

 

ES was far higher, despite same methodical case prep.

[sporting rifles]

I haven't tried anything other than match primers in my own 7 both Fed and CCI give same groups and similar velocities.

 

 

I did try using some Winchester cases a while ago whilst doing load dev (as opposed to Norma)

 

ES was far higher, despite same methodical case prep.

 

so you dont use mag primers either ??,I stopped using them ages ago as I couldnt get consistant groups,change the primers job done.