I think the most common standard I've heard of is in percent: i.e. 1-2% of the case weight. So if you are using say a .308 Winchester, w/ an average case weight of about 165gr, then a spread of about 2.5 gr should be perfectly fine, and still give you enough cases to work w/ from a given batch. For a .223, say about 1.5gr spread for an average case weight of about 95gr. It depends somewhat on how much your brass weighs. In the end, it's not a cure-all, but should cull some of the worse offenders. For me, I use the weighed and sorted stuff for the 600yd line, and the others for Offhand and RapidFire strings, as a grain one way or another isn't the limiting factor there, by any stretch. Depends on what you want.

Monte

Sorting brass by weight is not just a waste of time, but an IMMENSE WASTE OF TIME!!!



I have answered your question, now please answer mine. Why are you weighing brass?



You have a PM as well.



Scott

<tongue in cheek here> So you mean all those fairly successful competitive shooters that sort cases by weight are wasting their time?

OK, really, for most intents and purposes, you are probably right to some degree. I've heard people swear by sorting by brass weight, others by sorting by water weight (therefore volume), some by this, some by that, some by what phase the moon was in when that particular lot of brass rolled out of the factory. Obviously, some people swear *at* various methods as well.

How do you recommend segregating cases for LR shooting, lets say. Dunno what the OP had in mind particularly. Or are you of the school of "open the bag, prep the brass, load 'em and shoot 'em"?

TIA,

Monte

Poor old G. David Tubb wastes all that time weighing and uniforming his brass.

I don't care, darn it!! I started doing it one time because I read you were supposed to, and I'm not stopping now.

Oh yeah, for hunting rifles, I go +1 grain/-1 grain; for target types +/- 0.5 grain.

R-WEST

If weighting brass tightens a loose nut behind your butt plate then go for it.
But really you would be better of spending your time behind the trigger rather than at the scales.
Yes I know Tubb and other champion shooters in many disiplines weight their brass. However these few people have honed their shooting to the point that they can tell the difference. The rest of us use this as another "magic bullet" to solve our fliers, poor scores or other problem.
In Tubb's game if you can hold 2 minutes of angle you will shoot high master scores. And if you don't get caught too often in a wind change you will shoot right up thete with G. David himself.
That's right 2-minutes of angle. The X-ring is one minute, the ten ring is two minutes.
muck

Actually, the 'hold' required is considerably better than 2 MOA. Think about it. Lets assume you have a gun that shoots 1 MOA. I'm talking about all day long, all the way to the end of an 88 shot match, no breaks for cleaning. If your 'hold' is 2 MOA, and happens to break at the outer edge (of the 10 ring) and the gun happens to throw the shot to the side, you are well and truly out in the 9 ring, heading for the 8 or worse if you misjudged the wind. Of course, just to be perverse, every once in a while it happens the other way around, and stuffs you back in w/ a center X just to mess w/ your head.



Most of the people shooting Master and High Master are shooting guns that are sub-MOA or better, and have sub-MOA or better holds. Some reportedly have half-MOA call areas i.e. when the shot breaks, they expect the shot to be w/i half a minute from where they saw the sights at the gun went off.



<soap box on>

It's amazing how snooty some folk get thinking that HighPower is 'easy' and the guns 'dont have to be accurate' because of the size of the target in MOA.

<soap box off>



Given all that, I agree that I myself would probably benefit from an equal (at least!) amount of time spent dry-firing. But like someone said, weighing cases 'tightens the nut behind the trigger'; tying up one (possibly) loose end.



Oh, and btw, if it was that easy to 'shoot right up there' w/ Mr. Tubbs, I'm thinking he wouldn't be, what is it now, 11 time National Champion.



YMMV,



Monte

Ok, lets take this in a slightly different direction (and hopefully one that gets people _slightly_ less up in arms ;p )



If you were inclined (for whatever reason) to sort brass for shooting in competition, how would you go about it? Would you:



a) Sort by weight



b) Sort by water weight



c) Sort by neck runout



d) Do no sorting and just load and shoot



e) Some combination of the above



And fellows, please, if you are going to say something like 'method a) is a tremendous waste of time', try to be at least a little helpful and enlighten us unwashed masses as to what you _do_ consider a good use of time (as far as sorting goes. We *all* probably need more trigger time).



I generally use a) and c); a) to narrow the field of 'good' cases a little, and c) to cull any offenders that slipped thru. I'm looking for minimizing velocity variations for longer ranges, and b) is just too messy and time consuming for me. Everything else goes to the short line bin.



In all honesty, it does matter as to the application. For my 6.5-08 w/ a .292 neck and all neck-turned Lapua brass, I don't really worry about it because everything else is about as consistent as I can get it (and the weights generally tend to be w/i my normal 'band' anyway). If I get a new barrel later this year (possible), and decide on something other than Lapua for my brass, like Remington .260 Rem, I probably *would* sort by weight, as that stuff is notorious for a few 'oddballs' sneaking in here and there. Decent stuff otherwise, from what I hear. In my AR SR that I'm getting 1000 cases in for this week... I'm tempted to go the extra mile and sort out some cases that are as consistent as possible for the 600yd line. But in reality, this is my backup and 'loaner' gun, for when the 6.5-08 is in the shop, or the better half or the kids or a buddy from work wants to shoot. Odds are, if I never tell them the cases are or aren't sorted by weight, they'd never know the difference.



YMMV,



Monte

Those who say weighing the cases is a waste of time either have standards for shooting that are way too low, or they haven't shot enough and made comparisons to know the difference.

Checking for weight is really only a shortcut for determining volume of the powder chamber behind the bullet. The smaller the chamber, the higher the pressure and that difference can impact the velocity and subsequently the point on the target where the projectile strikes. It matters!

If I have the time I check water weight preferably. I usually do it on new cases. I've found that in cases the size of the WSM, and larger, there can be significant difference in their internal capacity, and much of the difference is reflected in the weight disparity of the dry case. Also, dry weight of the case includes variances in grooves which has no effect on internal volume, which is the reason that water weight is preferable.

A case in point. Some years back I opted to use 358 Norma Mag brass to form 338 Win Mag. Typically most domestic Win Mag brass has a dry weight of 237g � 2g. The Norma brass was quite consistent at 220g dry. The internal capacity was substantially larger in the Norma. That 17g difference dry equaled almost 100 fps per second in velocity drop. I had to add 1g more of the propellant to equal the velocity in the domestic brass. The reverse situation exists between WSM brass in domestic versus Norma. The uniformity of the internal volume of cases yields more consistent velocity and lower standard deviation, which is essential for long range shooting. For shooting in hunting situations under 200 yards, it doesn't much matter.

If your expectations are low, weighing cases either dry or by water capacity IS an immense waste of time. If you are a precision shooter and reloader, it is absolutely essential.

elde - But, those Prez Hundred shooters were all using the same, randomly drawn ammo. I'd be willing to bet that the shooter who won the event would shoot significantly better groups if he used all the prep tricks.

Dave King has done quite well in those matches requiring the use of drawn ammo. Mayhaps he'll chime in on the subject. Speaking of Dave, haven't seem him much since he won the Sable Trophy Thing from the "MatchKing....Hunting Bullet" thread.

R-WEST

I realize that we are not all of world-class ability, nor is our equipment, but, why not eliminate any/all possible variables, and build confidence in the mind of the buttplate nut? I'm guessing Mr. Tubb's mind isn't polluted with worry about how close this round is to that one, because he knows they're as close to the same as possible.

To throw another fly into the porridge, how about weighing primers? One of our better LR shooters has done some in-depth testing of the effects of primer weight on vertical dispersion. Sorting by tenths of a grain and using primers of exactly the same weight really cut down on the vertical stringing of his groups at 1,000 yards, so, it seems logical that there would be an impact at lesser ranges too.

Besides, for me anyway, doing that kind of stuff is fun

R-WEST

Here's another one for the non-believers: what about the (very successful) British Palma team? IIRC, they found that segregating loaded rounds by weight was advantageous (minimized veritical dispersion from velocity differences). Granted Palma shooters get handed ammo by the host country, so handloading and sorting your own ammo is out.

Monte

Good for them. Unfortunately, there is no more handout from the gov't., and everybody either buys or loads their own. There aren't many sources of decent commercial ammo in the bullet weights needed for HP, so most people roll their own. The commercial stuff does provide sufficient accuracy to clean the targets at 200 and 300. 600 is pretty much completely a load-your-own endeavor. Even the military teams load their own for it.

That and the 'cutoff' scores for President's 100 have gone up now that the M-1/M-1A and issue ammo are no longer the dominant force in Service Rifle. The AR's shoot better, easier.

Monte

What is the standard deviation most commonly used to include/exclude brass from a "set?" 1.0 grain? 0.5 grain? 0.1 grain? Other?

Thanks,
RSY

Doesn't the standard deviation depend on the mean weight of your brass and the use(s) to which it will be put? E.g., for informal shooting plus or minus 1 SD will suffice; for load development & accuracy perhaps half of that; for a match, half again (?); but for a match at 200 yds. or more, 0 SD.

Sorting brass by weight is a waste of time...