Brass and Loaded Ammo Weight Variation

[dranrab]

I just got a year older, and in celebration my lovely bride got me an electronic reloading scale. Prior to that I had a beam scale that maxed out at 110 grains. I piddled around weighing stuff this afternoon. I never saw more than 2/10 of a grain in variation in bullets, and that was with 240 grain .429 A-Frames. I measured some of my loaded ammo and some factory ammo. My loaded 6.5 Creedmoor ammo was more consistent than factory Hornady stuff. The least consistent component I encountered was new nickel Remington 257 brass. I saw fluctuations by as much as 4 grains.

Since this is all new to me, I don't know how to interpret it. Now that I have finished this post, I am not sure my reason for posting. I guess it was just interesting to me.

 

[witchhunter]

The difference is usually in the brass with commercial and NATO stuff. Lapua is more consistent as are most benchrest bullets. But weighing live ammo. there are several pieces that can be off just a little and it seems to be a lot. But, what if the brass is a little light and the bullet is a little heavy on some, opposite on others, you think the loaded round is perfect, but it's not.

 

[Jesse Heywood]

Without a baseline that includes the mass of the components for each round, you cannot draw any solid conclusions. If you weigh each case with primer, each bullet, and maintain traceability, you can then check your powder charge within the tolerances of your scale.

 

[dranrab]

I forgot I had a new box of Nosler 30-06 brass. I weighed 10 pieces of it and never saw more than .2 grains of variation. I weighed some different nickel brass in 223 and 44 magnum. Nickel has high variation. It makes sense that it would. Just piddling with the new device.

 

[ReloaderFred]

You're going to drive yourself crazy with that new contraption. It's like the old saying, "a man with only one clock always knows the correct time, but a man with two clocks never knows for sure the correct time".

The small differences you're measuring really don't amount to much at all. There are 437.5 grains in an ounce, so the difference of 4 grains in brass is really rather miniscule in the whole scheme of things. I know people who religiously weigh their brass, but they can't tell you where the differences in weight really are. Is it in the base, the rim or the walls of the case? If the primer is still in the case, does it have a three legged anvil or a two legged anvil?

Back when I first started reloading in the dark ages, the less I knew the happier I was. Over the years I've accumulated all sorts of equipment and measuring devices and happy moments don't seem to come as often with the use of all that gear. In the early 1960's, loading .38's meant they fit in the chamber and fired when the hammer fell, and hit the target where I was aiming. Then I bought a micrometer..... Oh Lord!

Then it was a chronograph, and that ruined everything. How on earth was I hitting the target with that crappy ammunition when there was so much deviance in the velocities??

Next came the electronic scale and weighing everything in sight. (sound familiar?) There was no way the cast bullets that I was casting and shooting so accurately could ever be consistent since they weighed as much as 5 or 6 grains difference between them, but still hitting the target in nice clusters at 50 yards.

I finally decided to use all the devices to set up my load and then forget about it and just enjoy the shooting. That resulted in more happy times for me........

Boy, that got long winded, and all over a simple scale.....

Hope this helps.

Fred

PS: You've got a good wife! Any woman who will buy her husband reloading equipment is a keeper.

 

[Rule3]

Nothing worse than deviant or deviance in velocities. We need to rid society of them

Deviations are not quite that awful!

I never trust electronic scales.

 

[Paddy]

One of the beauties of the beam scale is that it's hard enough to use that you're not tempted to weigh everything in sight.

 

[Hondo 60]

Some ppl mix headstamps.
They can be 5-8 gr different.
That's one reason I separate by headstamp.
No it's not perfect, but it's usually a lot closer than mixed.

ReloaderFred - love your post, (#5) it sounds oooohhh too familiar

 

[rcmodel]

Back when I first started reloading in the dark ages, the less I knew the happier I was

Man!
I wish I had of thought of that!!!

And no truer words have been spoken!

Don't over-think reloading.
It isn't Rocket Science.

Oh wait??
Propellants, pressure, burn rates, velocity, ignition systems, containment vessels, trajectory, drag, ballistic coefficients, energy transfer at impact, heat transfer to the chamber & bore, ejecta weight when figuring recoil, precise measurements to 1/1,000 of an inch, ------ Ahhhh?

Never mind.
It is rocket science.

That everyone can understand after reading a few good reloading manuals and a basic understanding of basic math.

Rc

 

[ReloaderFred]

Rocket Science?!

The ancient Chinese invented rockets and fired off thousands of them for pleasure and war, but they didn't know any of the "stuff" we study today. And they were happy doing it at the time and even the peasants could do it. Now we beat ourselves up with the minutia and worry about stuff we never thought of back when we started.

I'm not saying the knowledge is bad, or not needed, but it was way more fun back then to put a few rounds together and fire them off, secure in the knowledge that they worked and nothing got hurt in the process. Being naïve has it's advantages sometimes, but not always...........

Hope this helps.

Fred

PS: "Deviant": Differing from the norm or from the accepted standards. (The American Heritage Dictionary, second College Edition) :<)

 

[thump_rrr]

You have weighed everything in sight yet you don't know if your scale has any drift to it.
You should get yourself a set of check weights to confirm your scale is consistent in its measurement.
Another thing you can do is take a small item such as a 55gr projectile and color it with a marker.
Weigh that projectile, take note of the weight and set it aside.
Every time you want to use the scale weigh the same projectile and compare the weight to the previous time.
This will tell you if your scale drifts over time, temperature variations, drafts, etc.

 

[fguffey]

Since this is all new to me, I don't know how to interpret it. Now that I have finished this post, I am not sure my reason for posting. I guess it was just interesting to me.

Discipline: The last chance a reloader has to check loaded ammo is before firing. If the reloader does not sort by weight they are out of luck. I loaded 250 30/06 rounds and then weight everyone of them, there was 14 grains difference between the lightest and heaves. I had sorted by head stamp and weight the cases before loading. Had the difference in weight been caused by the powder charge it would have been difficult to concentrate on the accuracy of the loaded rounds.

Again, a shooter at the range was doing everything he could do to fire his pistol. He could not pull the hammer back, he could not rotate his cylinder nor could he swing the cylinder out. We offered to help him, we drove a bullet out of the forcing cone and back into the cylinder, that allowed his hammer to work etc.. As soon as we gave handed his pistol back he began loading his cylinder again. We started by offering him all the ammo he could fire, we offered to help him with his reloading.

The one thing we could not convenes him of was the last round locked his pistol up because it had no powder, the next part he had trouble believing was the big chance he was taking with the next round. It could be a double charge.

He was not happy with us, he left the range. We did all we could do in preventing him from destroying his S&W Model 66.

F. Guffey

 

[Reloadron]

Happy birthday and congratulations on the new scale. New scales always prove to be exciting and interesting as we start weighing everything in sight. Do 168 grain Sierra Match Kings really weigh 168 grains? How about those pieces of brass? What do they weigh and are they uniform?

Weighing loaded ammunition can make your head hurt. The problem is you really don't know what you have component by component and you are looking at the sum of all the components. Problem here is each component has an allowable tolerance. My Sierra 168 grain MK could be anywhere between 167.7 and 168.3 grains because while normally much better Sierra guarantees a +/- 0.3 grain uncertainty. The same holds true for my brass, it has a tolerance and even my primers but they always seem o be uniform. My scale may have an uncertainty of +/- 0.1 grain which gets passed along in my powder charges.

So if I weigh some loaded 308 Winchester and my loads are around 386.2 grains it doesn't mean much. I can have two or three rounds equally weighing the same 386.2 grains but the weights of the individual components vary. They just share the same sum.

This sort of stuff can cause loss of sanity and you find yourself OCD. Just enjoy the scale.

Ron

 

[dranrab]

Folks, I have no idea where the quote button is on this site. Thump this is in response to your post. The scale came with a test weight for confirming accuracy. The instructions also recommend a new zero every ten loads or so. I did check the scale for repeatable accuracy using a bullet of a known weight. It has repeated perfectly.

For all, I am not really concerned about any of the oddities I detected. I am a recreational shooter and hunter, so none of it would make a difference. New toy, just found it interesting and thought I'd invite comments to see if anyone had any particular concerns about what I had seen.

 

[Rule3]

Fred

PS: "Deviant": Differing from the norm or from the accepted standards. (The American Heritage Dictionary, second College Edition) :<)

As it pertains most commonly in use as a Medical term.

First Known Use of deviance

1944
Other Psychology Terms

fetish, hypochondria, intelligence, mania, narcissism, neurosis, pathological, psychosis, schadenfreude, subliminal


https://en.wikipedia.org/wiki/Deviance_(sociology)

 

[witchhunter]

My head hurts, I weigh only the powder and I don't want an electronic scale. I used to use a 50 grain bullet to calibrate my scale, then I heard that 50 grain bullets don't always weigh 50 grains! I checked, sure enough, they don't all weigh exactly 50. I bought a set of weights and use them, but who can you trust if not Sierra or Hornady? I shoot a lot of prairie dogs, and my requisite for a pdog rifle is one hole groups. I drop powder from a measure. Varmint shooters learn a lot from the benchrest guys, no doubt, but I shoot too many rounds in a day to weigh and measure everything, sort into groups, etc. I buy components in bulk, spend a lot of time on case prep, but I use all of them, I don't measure for capacity, I know it would help, I just don't go that far for my needs. Load and shoot, repeat (a lot) rebarrel, start over.