Inconsistent neck tension with Winchester brass

[cysoto]

I am on the second reload of Winchester .308 brass (all the same lot) and I am having some inconsistent neck-thickness measurements.

The brass thickness reads anywhere from 0.0115" to 0.0140" (per side) which means that, if I want to maintain the same 0.002" neck tension, I have to use neck tension bushings ranging from 0.329" to 0.334". Is this typical of Winchester brass?

Could I just use a 0.329" bushing on all of the brass and call it good?

Thanks!
Cy

 

[Dirty Deeds]

Re: Inconsistent neck tension with Winchester brass

I like .003" constriction in Lapua hulls,with moly.

I'm a fan of W/W 284Win hulls and their 7mm and 300Whizzums.

Other than that,I look to avoid it,though I've a few 223AI tubes eating the shit.

 

[427Cobra]

Re: Inconsistent neck tension with Winchester brass

I would be more concerned with Concentricity

 

[Known]

Re: Inconsistent neck tension with Winchester brass

I have noticed variability in bullet seating force with Winchester brass - much more variability compared to Lapua.

As far as consistency is concerned, go ahead and measure the runout of factory new Winchester cases compared to Lapua (I use the Sinclair tool) - you'll notice a difference as well. Lapua is very consistent for runout and seating force although you don't get as much case capacity as Winchester in .308.

However, a lot of competitive shooters use Winchester brass so I wouldn't give up. Just be prepared to cull out a number of sub-standard Winchester cases.

 

[Shady_Jay]

Re: Inconsistent neck tension with Winchester brass

That is what turning necks resolves. However the big question is: Has it affected anything in your shooting? If not, don't worry about it.

 

[427Cobra]

Re: Inconsistent neck tension with Winchester brass

Here is the reason a expander ball\mandrell can be a goodthing, it will force those inconsistencies to the outside of the neck, thus giving uniform NT, but most if not all of us induce case neck runout by using them, so take CKA advice and if your shoot consistently good, don't worry about it

 

[Fuzzball]

Re: Inconsistent neck tension with Winchester brass

"brass thickness reads anywhere from 0.0115" to 0.0140" (per side) which means that, if I want to maintain the same 0.002" neck tension, I have to use neck tension bushings ranging from 0.329" to 0.334". Is this typical of Winchester brass?"

That's about normal for most cases. And it's why I have no use for any bushing type sizers for factory chambers, use Lee collet neck dies instead, in conjunction with a body die when I need to "FL" size.

 

[cysoto]

Re: Inconsistent neck tension with Winchester brass

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: sacshooter</div><div class="ubbcode-body">Just be prepared to cull out a number of sub-standard Winchester cases. </div></div>
That makes a lot of sense! I had originally segregated the brass based on its weight. I should probably not worry about the weight variation and separate it instead based on brass thickness at the neck.

 

[former naval person]

Re: Inconsistent neck tension with Winchester brass

Get a K&M tapered expander and expand the necks after sizing. Don't use the factory expander ball. Better concentricity seems to be gained by doing it that way...pushing in rather than pulling the expander out. JMHO

 

[Hummer]

Re: Inconsistent neck tension with Winchester brass

Until you have the same neck thickness 360 around the neck and you are running it in a sizer you are going to get variation.

Uniform you neck thickness first. Then as recommended expand from the top with an expander rather than the bottom with decap rod.

Stress relieve your necks in a consistant manner.

Remove all internal carbon deposits from case.

Finally figure out a way to measure bullet pull forces as this is where the small SDs come into play. Bullet pull can be much higher than seating forces. As well when the bullet is held in the neck for awhile it will tend to bond or cold well with case neck.

You can have bullet pull forces of over 300 lbs and still be in ammo specs.

Try pulling some military match ammo with a collet type puller and you will get sick. Some bullets come out easily and some you have to really crank down on to grip them heavy enough to pull the bullets.

Until you get everything very uniform you are going to have more variation.

 

[Dirty Deeds]

Re: Inconsistent neck tension with Winchester brass

One can't size shit brass pretty.

The finite control inherent an expanderless bushing Sizer,is negated by feeding it shit brass. An expanderless Redding TiN bushing sizer,is the best way to fly.

Straight ammo of uniform neck tension,is never a concession.