Competition Tuning with neck tension

[Dimner]

What I’ve learned since I started tuning for long range is to use a side by side ladder format at as much distance as you can test.
Starting with a small enough bushing to hold a bullet on a jam and watch the overall performance as you increase hold with smaller bushings.

@JFrank I love this idea, where do you do this in your load dev? Do you do a basic powder ladder first, pick the best looking powder and then do the tension test?

 

[Dimner]

I started testing bushings early in the LD process just because the target results seem easier to interpret if I get close with the correct amount of bullet hold.
( Proactive rather than chasing my tail.)

Take a practical approach and you’ll find the path that suits your program.

Jim

I appreciate the reply.

Another question I always wondered.... When working with a new powder and bullet, I start off with the 300 yard ladder now that I have access to that distance. How do you guys choose what powder load to use? Is there any specific criteria?

My process has been to take two loads I get from reloading manuals that are at least a grain apart. Seat my bullet 0.010 off the touch point and Chrono 3 bullets each load. Then use those velocities in GRT/Quickload to tell me what charge weight gets me to my preferred velocity or pressure. Then I use this value for the 300 yard ladder. I figure this is good enough, but I'm curious how you experienced guys pick a powder charge to do your ladder.

 

[clowdis]

How does annealing effect neck size and how do you check it for consistency?

 

[TIMO]

Could you describe your process of how you are measuring the neck tension? I understand measuring the difference between the neck diameter of a loaded round (pressure ring) and bushing neck sized. I am experimenting with a different technique for consistency as I have noticed a difference in friction when seating a bullet.
Thanks
Tim

 

[memilanuk]

Pin gauges are your friend here. And yes, the surface condition of the neck ID will greatly affect how it 'feels' when you seat the bullet - to the point where it's almost a separate matter.

 

[over_thetop]

How does annealing effect neck size and how do you check it for consistency?

annealing softens the brass to get more consistent sizing, check the OD with calipers before and after bullet seating.

 

[TIMO]

Pin gauges are your friend here. And yes, the surface condition of the neck ID will greatly affect how it 'feels' when you seat the bullet - to the point where it's almost a separate matter.

Yes, I have been using pin gauges in my process and will sort the brass that way. Part of what I have discovered is that some of the necks are not consistent in thickness, usually not more than .0005 (one half thousandth) difference, hope I got the decimal in the right place. I can then segregate those pieces and utilize a different size bushing. I need an Arbor press with a pressure gauge to further measure the force required to seat the bullet and then test by sorting by measured force.
Each variable to be tested separately to validate if it has any value (based on the target).

Tim

 

[clowdis]

The reason I asked was that I tried neck bushings in my die to just size the necks that way but the seating pressure wasn't as consistent as using the same die with smaller bushings and a button. Necks were turned but I don't remember about the state of annealing. So I never went back to neck sizing with bushings only.