Case neck thickness

[patrick021]

Does anyone check case neck thickness if so what do you use?

 

[SidecarFlip]

A case neck micrometer. As a rule, I don't bother. I use quality (mostly Lapua) brass. Neck thickness and turning is fine for benchrest (F-Class) shooting but for hunting, the accuracy gained isn't worth the effort.

 

[FearNoWind]

I do check case neck thickness by using the simple deductive method. I turn my case necks to make sure they're a uniform thickness throughout their circumference then compare their overall size before and after bullet seating. Inasmuch as the bullet diameter is a constant the rest of the calculation if simple math.

 

[AZShooter]

I now use a ball micrometer.

Before I had one I would measure OD of loaded round with my caliper then subtract bullet diameter then divide by two.

I also check thickness with a K and N neck turning tool. It has a place for a dial indicator to measure wall thickness. It is shown in article below along with many other neck wall measurement tools.




Tools for Measuring Case Neckwalls

 

[bigedp51]

Does anyone check case neck thickness if so what do you use?

My Redding neck thickness gauge tells me more about my cases than anything else. Below a Remington .223 case with .004 neck thickness variation and this was average for these cases. Some of these .223 cases had as much as .008 thickness variations.

What I like about this gauge is just one twist/rotation of the case tells me a great deal about its quality. Cases like these will expand more on the thin side and warp when fired. I full length resize these type cases and use them for practice in my AR15 carbine.

When I find cases with .001 or less neck thickness variation I use them in my bolt action .223 and my AR15 A2 HBAR.

The Redding gauge is all I need and I have no need for more expensive gauges that measure to .0001.

 

[SidecarFlip]

Scold me if you want but I never check case thickness. Don't see any need, but then I don't load substandard cases anyway.

My rifles all shoot sub moa at 200 yards, thats good enough for my uses.

Too many other varibles in the reloading process that impact accuracy more than fiddling with necks...JMO.

 

[AZShooter]

Sidecarflip,

I envy your need to only shoot out to 200 yds.

This IS a site called LONG range hunting. So why not address factors in doing just that?

We shoot much greater distances when we hunt and to do so accurately and humanely we need to keep groups sizes to minimum. Why measure neck wall thickness? Quote from 6BR.com:

Extreme accuracy demands consistent case necks. If your case neck walls are thicker on one side than another, your bullets can be positioned off-center in the chamber, or tilted slightly off the bore axis. That means your bullets can actually start off crooked as they enter the barrel. (And "jamming" bullets into the rifling won't necessarily correct the problem.)

If some of your case necks are significantly thicker than others, it will be difficult to maintain consistent neck tension from one round to another. That can kill accuracy in a number of ways. Likewise, widely varying neck tension can cause nasty swings in cartridge pressures and velocities.

 

[SidecarFlip]

Well, I shoot a lot farther as well but my range capability is 250 to the backstop and 200 to the target stop. It's a private (mine) range. I dislike public ranges so I built my own complete with shooting benches and refreshments close by....

Consequently, unlike most folks that sight in at 100, I sight in at 200. When I say 200 yards, I mean only for load development. It' still sub moa at 200...... and it's still no neck turning........

If I was shooting F Class 1000 yards, maybe, then again, probably not.