Home Forums Hunting & Shooting Ask The Gunwriters Culling Brass

This likely should be in the reloading section, but this heading gets more experts. First off weight differences for hunting loads and precision rifle loads . Next neck thickness differences, again for hunting loads and precision rifle loads . I sprung for a tubing mic at someones suggestion. . They had gotten more expensive since the last time I looked, and the discount machine shop suppliers didn't have any so I bought one from KBC . Nice one , made in China. Even cheap Chinese machine tools are expensive. No way was I splurging for a Mitutoyo , my preferred brand.

I've found consistent neck thickness more important than case weight--but that's probably due to brass with consistent neck thickness not varying much in weight anyway.

I'm with JB, consistent necks are first for me. If I did weigh the brass I'd set any real outliers to the side.

With computerized mfg and improved QC methods, fewer defective components are getting out of the factory. Mics are the way to go if you want to squeeze every bit of accuracy out of a competition rifle. I don’t think for hunting rifles, unless they are LR rigs, that it’s worth the bother.

Of course, reloading is not always about practicality. 😄

Inside mics are excellent for determining how much your reloading die is reducing neck diameters. This helps when choosing bushings or deciding which of your dies is overworking your brass.

A while back, I compared an old timey 223 Rem Lee Loader to a Redding bushing and std neck sizing die. I found that my LL reduced the diameter to 0.220 whereas the std neck sizer finished diameter was 0.223.

The question is, how much is the neck squeezed down in the Redding std sizer before the expander gets it. That would be a job for an inside mic. 🙂

Steve,

It seems like you're talking about an inside micrometer.

Yup.
Tubing mikes check the wall thickness not the I.D. of the neck. That's what small hole gages are for.

Yes, I mistyped. I will correct.

https://www.24hourcampfire.com/ubbthreads/ubbthreads.php/topics/18509021#Post18509021

Followup question re the importance of neck thickness.

Are we talking about runout, ie., variation in neck thickness along the circumference of individual case necks? Or is variable neck thickness, with minimal runout, the greater concern?

I ask because the former condition might not result in variable neck tension. The latter will probably result in variable neck tension.

Ie., are we seeking concentricity or uniform neck tension?

Guessing we want both, but I really don't know.

They are referring to the actual variance in thickness around the neck. If it’s twice as thick on one side as the other there is theoretically no way your neck will be concentric after running through a sizing die. So, in actuality, case concentricity and thickness are related and both important.

My question is, what is everyone’s preferred method of measuring thickness? I can measure concintricity. No idea how to measure thickness. I just hit em with a micrometer at random spots? Easiest for me to do is outside turn the case necks just a smidge and that helps a significant amount.

I use a tubing mic. I mount the mic in a portable vice and measure the compass points (4 points). Then outside neck turn if required, which is often the case with less expensive brass.

A tube mic at three or four spots will do. You can also use a sorting tool like these:

For an accurate hunting rig, consistent neck thickness is what I look at.

Be aware that many commercially available tools to check neck thickness variations will transfer other things that get read out on the dial indictator as neck thickness variance....which isn't the case at all.

As always, do your homework and examine the process beforehand. -Al

There was a small learning curve to develop the right feel with the Redding tool.

How about focusing on case length ? I don't have the tools to trim or adjust neck thickness so I try to get all the same brass and make sure the case length is the same. The thought being that similar brass and the same length would amount to very close to the same weight. Am I out of line or is neck thickness that important ?

kwg

As with most of these threads, this type of thing doesn't not even need to be considered with "hunting" ammo. Buy good brass and do proper brass prep (trim to length and chamfer inside and outside of the case mouth). If you are shooting a lot of competition or benchrest, then and maybe then you can focus more on this type of thing. When I saw the thread title, "culling brass", that is always an ongoing thing when you are loading. With each step of the handloading process, you should be examining that brass. When I "cull", it's for split necks, loose primer pockets or any other deformity or imperfection I don't like.

When you say "buy good brass" what is the "good" we're buying? We would hope that consistent neck thickness is part of that. The unfortunate truth is bad batches of product get out of the factory now and then. I've even run into a box of Lapua 308 win. that had so-so necks. Trust, but verify.

Yes, this is hunting and target ammo but I am always trying to up my game. I have found that twice fired brass seems easier to get the results I want where once fired brass seems to need some "seasoning". Anyone else come to this conclusion ??

kwg

Case length is more of a safety concern. Long brass can be a problem as the length approaches where the chamber narrows. Worst case, it can pinch the neck and crimp the bullet when you chamber a cartridge.

Reloaders are strange beasts. What is unimportant to one person can be a bugbear to another.

The two questions I have were about neck thickness and case weight variations. JB suggested case weight tended to be consistent when neck thickness was as well. So my concern was neck thickness variation, what constitutes good, poor and toss ?

My tube micrometer isn't as deep reaching as Steve's. But it does have a vernier scale, so good to 1/10s.

I tend to sort brass so there's no more than .001" difference in thickness of the neck when measured all around the neck--especially if looking for the finest accuracy, whether in varmint loads (especially prairie dogs) or longer-range big game loads. (In my benchrest rifle I lathe-turn the necks to even smaller variation.)

But there's another factor involved than the neck. When brass has "lop-sided" necks, this not only affects bullet alignment in your loads, but tends to extend down into the case body. This often results in a somewhat curved case, even after "fire-forming" in an individual rifle and sizing in good died--which can also affect accuracy, sometimes as much as lop-sided necks.

That said, I still tend to measure and "cull" brass even for rifles where tiny groups aren't critical. This is because it generally takes far less time to develop consistent loads with uniform brass. A LOT of time can be wasted trying different bullets and powders because the brass ain't uniform. With consistent brass I trust in my range results if they result in consistent groups.

Of course, some hunters tend to choose the load which results in a single smaller 3-shot group--which is statistically useless. (Jim Carmichel pointed this out decades ago, but it's still how many if not most handloading big game hunters "work up" loads.) The same handloaders often have only a vague notion of how wind-drift affects even 100-yard groups, or consider groups with one shot farther from the other the result of a "flier." And it may be--but whether it's due to imperfect aim or trigger squeeze, or a tiny wind "gust" of maybe 2 mph, or some defect in the brass, bullet, etc. is another question.

Essentially, the case is part of the chamber, and if its lop-sided then the chamber's imperfect. But at least an imperfect chamber is "consistently" imperfect, while imperfect cases are not.

Yes, a lot of this doesn't matter when hunting big game at typical ranges, because big game is by definition a relatively large target. But it can matter at longer ranges, even well short of what's considered "long-range hunting" today. It definitely matters when shooting smaller targets, whether ground squirrels or paper targets.