I've been loading all week and I notice after weighing every few rounds my measure is sometimes off by .1 - it's never over the suggested maximum since I don't load hot loads.

It seems to happen no matter which powder I'm using.

Not sure why .1 difference, but wondering if it's something I should be concerned about.

I run a Dillon 550b (recently cleaned by Dillon) and reloading 9mm, 38 sp and 45 acp this week.


Thoughts?

Thanks in advance

I don't think so. But it matters to some and can matter more depending on the powder and if you are at a max load,more so with fast powders.

But again, the load data even at max is below spec so .1 grain is not that big a deal especially with a slow or medium powder,

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Still Running Against the Wind

If you're concerned, try a powder that meters more consistently.

If competing in bullseye competitions you might be concerned about point of impact being affected. If you aren't doing that and are just looking to maul some steel targets at the range for fun not a big deal. We have a 200 yard berm on the silhouette range at my club and sometimes I take a shot at the goose out there with open sights on my 6" GP100:P. One in awhile I hit it. Can't let the black powder rifle guys have ALL the fun.

You should be fine safety wise if you are loading near max but not over. Some digital scales wander a bit. Check your digital against a balance scale if you are nervous. It will help your confidence.

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Trucks and guns.

When your talking 10ths of a grain it is really hard to be accurate, scales are funny, on some how the powder lands in the pan gives a different reading. I would say calibrate your scale with a check weight that is close to the powder charge to try and get as close to the actual charge weight as possible.

Fast Pistol powders scare me because pressure isn't linear so I always load a little below maximum loads because you are putting such little amounts of powder in them. In pistol loads .1 more on 5 grains is a lot more then .1 more on 40 grains in a rifle shell. However if you are loading less than Max it shouldn't make a difference and you shouldn't have a problem. If you compare todays reloading manuals you will also see that the max loads have been reduced compared to in the 60's and 70's. That's because the lawyers got involved and scared the powder makers about lawsuits from people with blown up guns.

.1 may not really be a whole 10th of a grain. Most scales will only show to .1 so say your 5.0 gr load was really 5.08 just .02 would show 5.1. When I trickle my bench rest rifle loads I try to hit the point where the scale just reads the load i want. when setting up my 550B I drop 2 or 3 loads that I don't use then drop 5 loads and average the weight. All that said for a handgun at SD ranges you will never know the differencs. Don

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USN Retired/VN VET
M&P X5

It really doesn't make a bit of difference, especially in handgun cartridges! Read the literature for your powder measure and your scale. I have never seen one that claimed accuracy better than 1/10th grain! Do you really know if it is the charge that varies, or is it the scale reading?

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Gunsmithing since 1961

No, 1/10gr +/- isnt affecting any load, IF you are well off max. Some powders, like Clays, can get ugly quick if already at max. Add 1/10gr, get some bullet setback & you get a pressure spike. Fast burning powders dont have a linear pressure curve after you hit max. Doesnt sound like you ate even close.

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NRA Cert. Inst. IDPA CSO

Plus or minus 1/10 of a grain is pretty typical for scoop or a powder measure. You can get on the dot with a scale, but even that has some variances because everything does.

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"He was kinda funny lookin'"

I would suggest that you start weighing every single charge. Because a variation of as much as 1/10 grain observed every 10 or 20 throws is an indication that statistically it can be predicted that 1 in 200 or 300 throws may be off as much as 1/2 grain. Yeah, it really can get that extreme. It's why I do a Statistical Capability Study on every powder I reload with. Doing this allows me to identify powders that need to have every single charge hand checked and those that can be simply thrown.

BTW, a short list of powders I use that require hand weighing based on my studies using an RCBS Competition Powder Measure. Varget, Accurate 2495, IMR 4064, Unique, and Longshot. Note, just about any stick Rifle powder will require weighing each charge or the use of an electronic powder dispensing system.

Powders that are acceptable for thrown charges but that will vary to a statistically determined maximum of +/- 0.1 grains. CFE223, CFE Pistol, Vihtavouri 3N37, IMR SR7625.

Powders that are superb for consistency of thrown charges with a statistically determined maximum range of +/- 0.05 grain or less. Hodgdon H110/W296, Accurate #5, Accurate #7, and Accurate #9.

BTW, after doing all these studies I've concluded that the single aspect that determines whether a powder with throw consistent charge is the Particle Size. Go down that list above and you'll discover all of the poor metering powders have large individual particles, the moderately good metering powders have fairly small particles and the great metering powders have really tiny particles.

I will also note that it can be quite common to have "runs" with the poor metering powders where every charge is the same for 5 or even 10 charges thrown. Don't be fooled by these "runs" because those are also statistically predictable. The only way to be 100% certain about a specific powders metering properties is to throw 50 consecutive charges, record every weight thrown, and enter those readings into a calculator with a Statistics mode. That will allow you to determine the Standard Deviation and by multiplying that number by 3 you will have the total +/- tolerance.

In pistol cartridges, I'd have to say that in my experience a .1gr. difference isn't worth being concerned about. By way of example, I've tested loads with my Bullseye 45ACP, using Titegroup and 200gr. LSWC's, and with loads ranging from 4.4gr to 4.8gr., it didn't make a serious change in bullet impact at 50yds.

Does 0.1gr make a difference in a ~5.0gr pistol round? Geez, I hope not because no PM is gonna do better than +/- 0.1gr . . . and I'm not gonna hand weigh pistol ammo.

The only thing I do to try to keem my dumps close it ti fill the tube at least 30% full.......
then tape it a few times to settle the powder and toss three drops back into the top and then...........test for the grains that I want for the load.

Even max 9mm loads of today have a safety area so you should be good with a weapon in good shape.
Nato is pushing the limit and +P loads depend on the weapon.

Well statistically that may be but reality, it doesnt happen. If it did, there would be a lot more over pressure events with uberfast pistol powders. Pick a powder that gives 1/10gr accuracy, it will never throw 1/2gr over, never seen it, never will unless your measure is broken. If you can get 10 charges to avg 10 separate throws, you wont ever get a 1/2gr surprise imo.

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NRA Cert. Inst. IDPA CSO

With very fast powders and heavy bullets, I would certainly stay away from the top of the spectrum to accommodate variations you can't realistically avoid.

I use Clays with 158's in .357 cases and stay way from max loads for this exact reason.

Plus or minus a tenth of a grain is not an issue. Every manufacturing process has a tolerance, even if it is measured in light bands. When you get right down to it, measuring powder is the same process. If you want to measure every one of them, go for it. If your powder charge only varies +/- a tenth you are blessed. Load em and shoot em.

Be safe first and let common sense apply to the rest.

Have a blessed day,

Leon

On most scales 5.04 is going to read 5.0 and 5.05 is going to read 5.1. Unless you have very precise calibrated measures I wouldn't worry about it.

Does 1/10th of a grain matter ? No.

Check out 3 or 4 reloading manuals their max load will vary more than a 1/10th of a grain. Sometime much more.

Some powders will meter better than other. But even with powders that meter great you may get a 1/10th + or -. Bullseye, W231, HS6 will meter quite nicely. Others like Unique or other flake of stick powder may not.
I prefer a powder that meters well like the ones I listed. And I hardly ever load pistol stuff to the max.

I have a weight standard set that I check my balance beam scale with. Then once I have my dump set, I weigh & check 6 or 8 or 10 dumps. Usually check a dump near the first of 100 rounds & at the end of 100 rounds. ( I load on a Dillon 550 )

Rifle stuff using stick powder is a totally different animal ,, weigh each charge. Except AR stuff where I use a ball powder and load on the Dillon.

I have a electronic scale, but I don't trust it that much. I use it to check stuff like brass, bullets, or stuff like that. But I prefer my balance beam to check powder.

Does it matter ? In truth NO. that's the standard deviation for mechanically weighed or thrown charges. Perfectly normal. You have to go to more than ordinary tools and procedures to do better
Keep on keepin' on , you doing just fine.
Gary

I'm not so sure that weight based measurements of powder produce better results than volumetric measurements. I see little if any improvements in accuracy with hand weighed, trickled powder charges than with charges straight from the powder measure.

You won't often find factory ammunition where each round is within 1/10th of a grain when weighing the charges.

There's a video on youtube of a tour of a ammunition factory. Can't remember which manufacturer but you can clearly see in one part were powder charges are done by volume, not weight. Makes sense when your loading a couple million rounds a day.
I have a RCBS uniflow and once set will drop hundreds of charges (500 being the most I've done before resetting for another powder) that have varied no more than +/- .1 grain with ball powders. Obvious to me, small grain ball powders would be more accurate. They would settle more uniformly (don't know the proper term) than flake or extruded powders. I would think the only way your measure would go off by half a grain was if the lock nut came loose or your measure was worn out and leaking.
Also keep in mind all scales have a tolerance, beam or electronic. I've seen my Lyman M5 beam move .1 when the A/C kicks on in the house.

Collo;

Good point about the A/C or fan in the area.......!!

Last summer the wife had a fan panning left and right in the next room..............
sure enough, I had to get up and shut the door !!

Even a open window and a breeze from outside can mess with you.

Good loading.

Drop ten charges into your pan, weigh it on your scale, divide by ten. Adjust and repeat until desired charge is obtained. Load ammo, and don't sweat the 10th of a grain variance.

I agree with Troystat and in addition I recommend weighing "by difference" to be as accurate as possible. This is how an analytical chemist would weigh in this situation. For example:
1. Weigh the primed case. Record, memorize, or otherwise know this weight.
2. Charge the primed case with gun powder.
3. Weigh the upright charged case and subtract the weight of the uncharged case to give you the most accurate weight of your powder charge.

I basically agree with other posters recommending you not worry about the 0.1 grain deviation.

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Scoundrel & Ne'er-Do-Well

I've been loading 10mm and others with 800x.. it's like Corn Flakes. I back off max. charge by half a grain and check when I feel the powder drop bind on the powder, I find it can vary up as much as 3-4 tenths. Since I am still just below max. I push a bullet in and go shoot it.

When preparing a new load it is common practice to ladder up in 0.2gr increments to see any noticeable difference at all. POI will not be affected much by a 1/10th variance due to all the stacking tolerances. Unless you are shooting seriously competitive 25+ yard BE events and trying very hard to eliminate variables, 1/10th of a grain won't make any serious difference to POI. When necessary, use a baffle in your measure for certain powders, keep it at least half full and load away.

Well we all load by volume if using a measure but that measure is set by weight, same as factory. Volume varies with each powder, & even techniqie, weight is a constant, why you dont see volumetric data in manuals, but for lee, which i have always found suspect.

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NRA Cert. Inst. IDPA CSO

That an internal volume of case will vary more than 1-3/10, your 1/10gr diff is not likely to cause issues, but it is powder & caliber/case dependent.

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NRA Cert. Inst. IDPA CSO

I do not agree with taking the average of X amount of throws or charges. All you get is the average of 10 or 20 or however many you took.

If you are aiming for say 5.0 grains and the average comes out to more or less how do you know which one was over or under> One could be 4.9 and another be 5.1 or one is 4.8 and the other 5.2 etc etc.
What happens if one is 4.0 grains and another is 6.0 grains!!??

If you want a true average you need to weigh each and every drop and then take the average.

Just like a chronograph you have high, low, ES and SD.

That said as in a previous post. It simply does not matter for 1/10th of a grain. Benchrest guys may obsess about things like this but there is more variance in the weight of the handgun bullets.

How many Angels can dance on the head of a pin.??

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Still Running Against the Wind

Don't you just love it when you can feel the powder unit cutting through a bunch of powder on the stroke of the handle.

Makes you wonder if that one will be a full load or the next one on the light side..??

Carry on.

^ Like I mentioned 800x is chunky stuff. A heavy charge binds as I cut through.

The next charge comes from the bulk hopper so it will be a full charge.

Groo here
JD Jones [SSK] once told me in loading handcannons[or most anything
else]
If you can get in trouble with a .1gr increase in charge.
You are using the wrong powder or are way too close the edge.
Your loads should be dipper or dropper safe.
And he loaded HOT.