Neck turn newb

[lightflight]

In my quest to learn how to reload with greater precision, I have been looking at dies. I stumbled upon Redding Competition dies S bushings etc.
In further research on the bushing type dies I read about neck wall thickness and turning necks for consistancy etc.

This is where it seems like there is a lot of disagrement, speculation, and hear say enter the current picture.

I have a barrel on the way in 7mm Rem mag with a standard chamber as far as I know... I didn't request any special dimentions.

My questions are as follows:

1. With a Standard chamber will neck turning my brass Help or hurt? Claims I have read Is that it already is too lose a chamber that it will hurt accuracy?

2. I see Neck Reamers/ Outside neck turning? One or the other or both?

3. I'm looking at getting set up with foster classic type. Comments?

 

[dkhunt14]

My questions are as follows:

1. With a Standard chamber will neck turning my brass Help or hurt? Claims I have read Is that it already is too lose a chamber that it will hurt accuracy?

2. I see Neck Reamers/ Outside neck turning? One or the other or both?

With a standard chamber you can skim them and it might help a little. When you neck turn it makes the bullet more centered and makes the brass more consistent. You really should get a tight necked gun for full benefits. Neck turning is way more accurate then reaming, I can hold .0001 in turning. If you are going to do it get a K&M and the expander mandrel with the holder. K&M is one of the easiest to adjust. You should also have a ball micrometer to measure the wall thickness. K&M also has one with the spindle ground specially so you can measure right up to the neck shoulder junction. If you are just skimming you can get away without it. Matt

 

[lightflight]

Well my CBI Criterion has been on order from jim at nss for 2 months. Maybe I can ask him about the neck specs and if I have options at this point

 

[FearNoWind]

I had never turned a neck until last year. What I found was that turning the necks allowed me to get better control over neck tension (the amount of force holding the bullet in the neck) and that control helped improve accuracy.
Let's assume that my chamber measures .320
My unfired new brass neck measures .314
Same brass, with bullet seated .319

I have .001 expansion room for the round so the tension on the bullet at ignition is .004
After preparing the fired case for reloading, using a bushing die, my relative dimensions don't change. If I turn the case necks .001, the newly formed brass neck measures .312 (remember we're taking .001 from the entire circumference) After I seat the bullet my neck is .317 so I have more room for the neck to expand at ignition which puts less tension on the bullet as it leave the case.

Neck turning, IMO, is not an exact science and how consistently we can control neck wall thickness depends largely on how accurate our turning equipment is. But reducing neck tension, if only slightly, can help accuracy and may slightly improve MV.

However, for general hunting purposes, I don't believe neck turning provides enough advantage to make it worth the investment in time and money. For the bench rest, F-Class, Tactical competitor it seems to help when the number of X's breaks ties. But for hunting of any variety I wouldn't go there.

1. With a Standard chamber will neck turning my brass Help or hurt? Claims I have read Is that it already is too lose a chamber that it will hurt accuracy?

IMO, that's ridiculous. Admittedly, neck turning can be overdone to the point where the bullet essentially falls out of the case but I'm not acquainted with anyone who would push the limits to that extent.

2. I see Neck Reamers/ Outside neck turning? One or the other or both?

They both do essentially the same thing. What we're tying to do is reduce the neck wall thickness to minimize the tension on the seated bullet. But neck turning, IMO, is more accurate because it uses the neck's original diameter to guide it equally on the mandrel when turning. Using a reamer provides no reference point other than the reamer itself.

3. I'm looking at getting set up with foster classic type. Comments?

The "Forster" Classic is a case neck trimming tool, not a neck turning tool.

If you're looking for quality dies for neck sizing there are a number of very good bushing dies available. The thing I try to avoid in using sizing dies are those nasty neck sizing buttons used in conventional sizing dies (use a neck expander mandrel instead) and making sure the bushing I use is perfectly matched to the final size I want to achieve once the bullet is seated.