# How critical is measuring powder to .01 grains

I'm gonna out on a limb and say there isn't a human that can shoot the difference in .01 grains of powder. That's like half the weight of a single kernel of Varget.

In the forum the accuracy nodes in a ladder test range between 1 to 2 grains With accuracy stable in that range. If that node is between 60 to 61 grains, and you decide to load 60.5 grains why is loading to .01 grains critical?
.1 or .01 grains? I don’t get that critical for the most part. How many rifles/shooters are capable of shooting the exact same groups every group string? But if you venture into smaller cartridges and faster powders like used in my hornets cases then 1/10 grains make drastic differences.

.1 or .01 grains? I don’t get that critical for the most part. How many rifles/shooters are capable of shooting the exact same groups every group string? But if you venture into smaller cartridges and faster powders like used in my hornets cases then 1/10 grains make drastic differences.
The question you should be asking is this.
How important to me is vertical string a elr range.
If it is not important to you than don't worry about it.
If minimal vertical stringing is important to you than worry about it along with all other steps in brass prep

First, let's not forget that a grain isn't just a grain, nor is a tenth of a grain just a tenth of a grain; it's a percentage of the total charge weight. A tenth of a grain can be a fairly substantial amount of powder if you're loading a 25 ACP or even a 22 Hornet. It is absolutely insignificant if you're loading a 30/378 Weatherby. There, even a full grain of powder probably won't show nearly as much influence on pressures as that tenth would in the Hornet.

Match the percentage to the case being loaded, and you'll save yourself a lot of frustration down the road.
Those smaller cases aren't shooting our to any distance so they're powder charge accuracy is not fussy. Also measuring to 0.01 of a grain, seriously?

In my opinion this all depends on just exactly what you are doing and what is an acceptable outcome.
Most people here chase the smallest SD and es possible. Why?
Because even a difference of 5 fps can be a big difference at extended ranges.
If one is trying to eliminate every variable possible than this is one variable that can be taken off the table with ease.
When we look at probably the most popular cartridge the 6.5 need more we can show where even .02 may make a difference.
Let's say the mean velocity of said 6.5 is 2800 fps and it takes 40 grains to get there. That means every grain is responsible for 70 fps. And every 10th equals 7 fps
The difference at 1 mile for 7 fps at my elevation is .6 minutes in elevation (with my load) between just one 10th grain deviation. Measuring to the hundredth takes this out of the equation. This is one of many things people do to get single digit es and as small as possible sd

Most loading scales also at plus or minus on top of that meaning that .1 could be .025 or .175 before the reading changes.
This can cause .2 deviation between loads easily. If your tightest powder measure is .2 deviation that you probably won't ever see single digit es or SD and your down range vertical dispersion will probably show it.

There are plenty of scales now days that will weigh a charge within .02 in 10 to 15 seconds.

If you are shooting elr charge weight is definitely within bounds for worry especially with low volume cartridges
If shooting 1k and you're really not worried about vertical dispersion much than a 10th would probably be just fine
That's good mathematical explanation of how 0.10 grains could affect velocity, thank you for the analysis. As a reloader I would postulate that as one gets closer to the max load and/or a to a compressed load, the powder measurements' precision and accuracy become even more important as the velocity/pressure tends to climb in a non-linear fashion around the top end.

In the forum the accuracy nodes in a ladder test range between 1 to 2 grains With accuracy stable in that range. If that node is between 60 to 61 grains, and you decide to load 60.5 grains why is loading to .01 grains critical?
Unless you are a Tier 1 competitor It's immaterial. You won't be able to trace it as a source. There is just too much other noise in the reloading and shooting process. Personally, my margin of error is +/- .1 grain and my SD and ES are fine. It is more likely something else downrange. Like the wind, shooting fundamentals, and so forth.

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At a certain point we all get to a point of diminishing returns. I used to be hyper critical of my loads when I first started loading. Now I spend more time on shooting than loading. It's whatever you care to spend your focus on. some might love the challenge of making a better load. I prefer to be outside at the range, or better yet, out in the wild by myself.

If your loading process and shooting ability is dialed in enough for .01 grain powder resolution matters, then you’re the exception, not the norm.

The GemPro 250 is still somewhat available. My Pact scale is pushing 7 years old, so I ordered a GemPro yesterday, and it seems to have already shipped.

I've been shooting a 6 BRA in 600 benchrest matches reloading Berger 105 hybrids with Varget. I was using a RCBS Chargemaster, and would see ES of around 20 and an SD right around 10. I started trickling with the RCBS and verifying and correcting with a Creedmoor Sports TRX 925, and all my ES and SD's fell with more than 1/2 coming in with ES around 10 and SD about 3.

BrentM, it is rare to see BR shooters weighing charges. Most of use a quality measure.

I purchased a bunch of test tunes and weighed a bunch of charges. Took them to our tunnel, shot 5 groups with them and 5 groups with thrown charges. The agg with the thrown charges was actually better, not by much. Prob more shooter error.

Get a good quality measure like a Harrels and put the effort into case prep and steering the gun.

JMHO
Don't you mean a "quality dispenser" that dispenses accurate quantities of powder and not an "accurate measure" which are scales which measures weight?

That's good mathematical explanation of how 0.10 grains could affect velocity, thank you for the analysis. As a reloader I would postulate that as one gets closer to the max load and/or a to a compressed load, the powder measurements' precision and accuracy become even more important as the velocity/pressure tends to climb in a non-linear fashion around the top end.

...ABSOLUTELY NONE !!! And anyone who says it is, is a lunatic.... a single little unseen buff of wind will have far more affect and effect than 0.01 grains of powder..