Weight-Sorting Cases: Is it Worthwhile?

Regardless of how much you spend, brass per cubic inch weighs the same for every cubic inch.

Spending big bucks on brass is just an expensive way of having the manufacturer weight sort the brass for you.

If two pieces of brass weigh the same, they will both displace the exact same space within your chamber. The only exception would be if the cases were made of different materials, but that's a stretch, if its brass.

One could argue that case wall thicknesses in different places might affect muzzle velocity, but within the same head stamp that would be an extreme perspective.

If you cannot get low velocity spreads among cases of identical weight, look to another source of variability. One most often overlooked is freebore diameter and neck clearances. If a bullet does not start into the rifling straight, you cannot expect it to fly straight and you cannot expect low velocity spreads due to the variation in force required to get the bullet into the rifling.

To understand this, measure the diameter of the bearing surface of a bullet, then open the micrometer just 0.001" and look at the available angular offset that you can apply. That is how much you bullet can cant inside your chamber if you have just 0.001" freebore diameter clearance, and you probably do.

Of note a 22BR PacNor reamer is made to a freebore diameter of just 0.2242, when a bullet measures 0.2244, because they reamer maker will never work to the minimum dimension and the lath always cuts it oversize. People often think of these BR cartridges as some secretly mysterious voodoo that are just accurate... Well they are accurate for a reason.
 
Last edited:
The theory of turning necks…. The case is not uniform at the mouth. What are the chances the case is not uniform in the body either.
So the brass is fired once, how many times before it “ evens out “. If it does, then how long would it take the non turned neck to do the same. So even though the case outside diameters may be uniform, the inside is not, at least for some time. Measuring case volume seems the best way. When I am ready for better than 1/2 moa, ( new barrel ) I am getting better brass and not weighing anything… still.
 
south pender said:
who here weight-sorts cases? Has it made a difference in accuracy? I have a new batch of lapua 6.5x55 cases that are pretty uniform in weight. (this is after i've trimmed and neck-turned them.) the range in weight, from lightest to heaviest, is a little over 1.0 grain. If i weight-sort them into two groups, lighter and heavier, the range in weight in each group drops down to about .5 grains. So, if i shoot 5-shot groups, the maximum case weight difference within the group will be .5 gr., and for most groups, less than that. Is this much reduction in case-weight variation likely to lead to improved accuracy? What are your thoughts on weight-sorting brass.
Click to expand...

o c d
 
As said, volume is set by the chamber, doesn't change. If you put more brass into it, there's less room for other stuff.

I've weight sorted a bit, usually just to find that 1 piece of brass or that 1 bullet that happens to be further out than the rest but good stuff is so good and consistent now its probably not worth bothering with.
One of my best group/score was when I spilled my nicely sorted box of ammo before a match and threw them all back in the box randomly.

If its a box of factory ammo, like for sighting a buddy's hunting rifle with what he wants to shoot in it, I definitely weight sort those in order.
 
wasa said:
I have found sorting my 300 Savage and 243 Winchester brass by weight makes a noticeable difference in accuracy at 100 yards. The Gevelot 300 Savage brass weighs many grains more than my Remington or Dominion brass. I want to say significantly more but i would have to check my notes. This is with Varget and 150 gr projectiles.

Same for my 243. I now sort my rifle brass when reloading.

YMMV
Click to expand...

Sorting by head stamp DOES make a difference, sorting quality brass, not so much. Most shooter myself included would probably never notice the difference on paper and would never notice it in a hunting situation. BUT if mentally you feel the need to do it then by all means do it. Shooting and target shooting are defiantly a game of the mind ... SO if you mind then it does matter.
 
Lead hammer said:
The theory of turning necks…. The case is not uniform at the mouth. What are the chances the case is not uniform in the body either.
So the brass is fired once, how many times before it “ evens out “. If it does, then how long would it take the non turned neck to do the same. So even though the case outside diameters may be uniform, the inside is not, at least for some time. Measuring case volume seems the best way. When I am ready for better than 1/2 moa, ( new barrel ) I am getting better brass and not weighing anything… still.
Click to expand...

I'd like you to explain how measuring case volume will indicate body uniformity.

If the side wall is thick on one side, it will simply be thinner on the other side by the same amount and volume is still the same. Side wall uniformity is not relevant to anything between two fire formed cases that weight the same.

Neck wall thickness variation can certainly affect bullet alignment, (That's why neck turning is important) but side wall uniformity in the body, is just not relevant.
 
Waste of time.

Where is the difference of weight made up between each individual piece of brass? Is that extra weight always found in the neck? The case mouth? The body? The web?

Just because two pieces of brass weigh the same, doesn't mean that the brass uniformity is identical between those pieces. You still probably have two inconsistent pieces of brass, that are only consistent by one arbitrary metric.
 
Shoot your groups. If you get a single shot with an unusual elevation, then mark that brass and keep the brass from that group separate to check afterwards. You might find something different about that one piece.
 
kthomas said:
Waste of time.

Where is the difference of weight made up between each individual piece of brass? Is that extra weight always found in the neck? The case mouth? The body? The web?

Just because two pieces of brass weigh the same, doesn't mean that the brass uniformity is identical between those pieces. You still probably have two inconsistent pieces of brass, that are only consistent by one arbitrary metric.
Click to expand...

So when a case is under pressure and blown out to fit the side walls of the chamber, you are saying that in this state, two cases of identical weight will display different amounts of space within the chamber?

If yes, then the variation would need to exist within the case extraction groove. So your contention is that there is such a tolerance variation in extraction grooves of a particular headstamp, that it negates the value of weight sorting?

Again, a case under pressure expands to fit the chamber, so in this state, I would like to understand how a weight change which is a direct correlation to volume of brass, does not result in a corresponding average change in pressures and therefore velocity.

Or are you just saying that the affect of a few grains of brass on pressure may occur at a theoretical level, but is just too small for "you" to notice when shooting? "You" being a non bench rest, non f class plate shooter.
 
jimbo14 said:
Shoot your groups. If you get a single shot with an unusual elevation, then mark that brass and keep the brass from that group separate to check afterwards. You might find something different about that one piece.
Click to expand...

^^^ Great Advice!!!^^^
 
Maple57 said:
So when a case is under pressure and blown out to fit the side walls of the chamber, you are saying that in this state, two cases of identical weight will display different amounts of space within the chamber?

If yes, then the variation would need to exist within the case extraction groove. So your contention is that there is such a tolerance variation in extraction grooves of a particular headstamp, that it negates the value of weight sorting?

Again, a case under pressure expands to fit the chamber, so in this state, I would like to understand how a weight change which is a direct correlation to volume of brass, does not result in a corresponding average change in pressures and therefore velocity.

Or are you just saying that the affect of a few grains of brass on pressure may occur at a theoretical level, but is just too small for "you" to notice when shooting? "You" being a non bench rest, non f class plate shooter.
Click to expand...

Weight Sorting – Fact or Fiction

Also, Applied Ballistics has done a lot of testing on this subject, and found that weight sorting brass is a useless exercise.
 
If you really want to be obsessive; why not weight sort your already weight sorted cases in order of lightest to heaviest, organize them like that in the box and shoot them in that order? That way you'll have the smallest possible difference in weight in every group or string you shoot; a group of 5 would have 10th the variation as a box of 50. I was shown that one by a guy who ran all his cases through a lathe to square the face of the caseheads and match rim thicknesses before he would even think about sorting his cases in order of weight.

Why stop there? After weighing all your primers to 1,000,000th of a grain why not load them in order? Primer compound is about 1000 times more powerful than gunpowder.

I'm too busy sorting my socks into lucky and unlucky piles. Gives me confidence. ;)
 
You must log in or register to reply here.
Back
Top Bottom