Weighing ammunition?

[OneStory]

Let's say you are loading 9mm ammo using only one type of primer, case, powder and bullet....

How much variance is there, in grains, amongst the finished rounds?

Which component typically has the most weight variation - the case or the bullet?

 

[dirty_sanchez]

I'd say percent wise the bullet's would have the largest variation.

The powder drop should be the same give or take a tenth, the primers would be the same, but each different brand of case weighs different, and there's likely a grain or two different for a mfg's. 115 gr, 124gr, or the 147 gr. all coming out of the same box.

But I'm just making all of this up thanks to a free night on my Holiday Inn Express Points

Dirty

 

[Storm52]

.05 grain variance in powder is pretty standard deviation. I've never weighed bullets since I order them by the 1000's. Since I'm not shooting bullseye, all things considered, I don't really concern myself with minute variances. The case weight doesn't come into play, unless you are weighing finished rounds and even then it has no bearing on the critical weights (powder/bullet).

 

[returningliberty]

Cases will vary substantially, even between brass of the same manufacturer and the same number of times shot (that's been my experience, anyway). When loading 9mm, a total variation could be upwards of 3gr or more, and that could Easily conceal a double charge with some powders.
Just weigh the powder charge every 10th (I weigh every five) and you're fine.

 

[LACamper]

I knew some .22 benchrest shooters would sort their rounds into groups by weight and by rim thickness...

 

[Quickdraw22]

I knew some .22 benchrest shooters would sort their rounds into groups by weight and by rim thickness...

This affects accuracy quite dramatically. I've seen some impressive results from guys that sort their bulk pack ammo by weight and rim thickness.

 

[OneStory]

Cases will vary substantially, even between brass of the same manufacturer and the same number of times shot (that's been my experience, anyway). When loading 9mm, a total variation could be upwards of 3gr or more, and that could Easily conceal a double charge with some powders.
Just weigh the powder charge every 10th (I weigh every five) and you're fine.

So weighing loaded rounds isn't accurate enough to reveal no-charge and double-charge rounds? How does the factory do it, if at all?

Weighing powder charges slows things down too much for me.

What are some ways to weigh powder charges faster?

 

[returningliberty]

So weighing loaded rounds isn't accurate enough to reveal no-charge and double-charge rounds? How does the factory do it, if at all?

Weighing powder charges slows things down too much for me.

What are some ways to weigh powder charges faster?

That's correct. Unless you pre weigh bullets (I do this with rifle bullets), and brass and sort them, wich will slow you Way down, weighing full cartridges is not going to help you.

The factory Doesn't.

If you dont have the patience to be safe please don't roll your own.

Also, your setup / process could be slowing you down. What press, scale and process are you using?