Electronic Vs Mechanical Scales Test

[Baldrick314]

I recently bought the RCBS Chargemaster 1500 Combo Unit. I haven't loaded a whole heap of ammo with it so I'm setting out to do a comparative test of the accuracy of the Chargemaster against my RCBS 5-0-2 scales.

I've loaded 10 rounds on each of the scales so I can shoot a total of 4 groups of 5 shots.

The cases were prepped identically in the following fashion:
All cases are once fired federal that were full length sized, trimmed to the same length, flash hole & primer pocket uniformed, neck turned to uniform thickness, primers seated with RCBS hand tool.

Load is federal 210 large rifle primer, 42 grains of 2206H, 168 grain Nosler Custom Comp (weighed so each projectile is the exact same weight), OAL is 2.330" measured with a Hornady Comparator. All loaded rounds were checked for concentricity. Calibre is 308W

So hopefully the weather plays well Saturday morning so I can get a true measure of which instrument produces the best results

[Westy]

If you have a crono it'll tell you a lot of what going on as well!!!!

[Baldrick314]

If you have a crono it'll tell you a lot of what going on as well!!!!

I do have a chrono but find it hard to shoot good groups over it cos I'm worried about putting a bullet through it

Might do first group of each just at the target and second group over the chrono. Assuming it's good weather

[Apollo]

Not exactly sure what you might achieve by your comparison.

Most all electronic scales have a delay factor in which they will not react to weight being added until they calculate again from the last measurement. It depends a lot on how quickly the powder is being dropped into the measuring pan. Mechanical Scales can be as accurate as they are set up and calibrated and should react as soon as weight is added like say one granule of powder and the scale allowed to settle.

The Chargemaster has an accuracy of +/- 0.1gr so in reality it can show a variation as much as 0.2gr of powder which in a reasonable load isn't all that much but is enough to change accuracy performance as long as your own accuracy is up to the task. In my view a possible error of 0.2gr is way too much especially with small charges around 20-25gr of powder, that's like 10% error.

I would have thought a better comparison would have been to drop 10 charges from the Chargemaster into some sort of individual containers and then re-weigh each charge to see what the varietion may be and even weigh those charges using the Mechanical Scales. Both scales should be ideally calibrated with a known accurate weight close to that you are comparing like a 40gr bullet or better still 40gr of Check Weights.

Most Chargemaster Combo Scales I know of have been modified to slow their trickle speed down in an effort to give more consistant results, the straw in the tube trick and also the modified programming of the scales themselves.

Hope you are happy with your product.

[Baldrick314]

Not exactly sure what you might achieve by your comparison.

Most all electronic scales have a delay factor in which they will not react to weight being added until they calculate again from the last measurement. It depends a lot on how quickly the powder is being dropped into the measuring pan. Mechanical Scales can be as accurate as they are set up and calibrated and should react as soon as weight is added like say one granule of powder and the scale allowed to settle.

The Chargemaster has an accuracy of +/- 0.1gr so in reality it can show a variation as much as 0.2gr of powder which in a reasonable load isn't all that much but is enough to change accuracy performance as long as your own accuracy is up to the task. In my view a possible error of 0.2gr is way too much especially with small charges around 20-25gr of powder, that's like 10% error.

I would have thought a better comparison would have been to drop 10 charges from the Chargemaster into some sort of individual containers and then re-weigh each charge to see what the varietion may be and even weigh those charges using the Mechanical Scales. Both scales should be ideally calibrated with a known accurate weight close to that you are comparing like a 40gr bullet or better still 40gr of Check Weights.

Most Chargemaster Combo Scales I know of have been modified to slow their trickle speed down in an effort to give more consistant results, the straw in the tube trick and also the modified programming of the scales themselves.

Hope you are happy with your product.

I really just wanna see how much that variation would affect accuracy. It's just for fun.

I was gonna change the settings on mine to slow down the trickle speed because I was getting a few that threw .2 over the nominated charge but then I stopped using the dust cover and it eliminated a lot of that variance.

[Wedge]

This test is timely for me as I'm just getting set up to do some reloading in the future and trying to decide between digital scales/powder thrower and a balance beam scale. By my maths a 0.2g variation on a 20g load is actually 1% - so my question is - will a 1% variation in load make a significant difference - assuming constant shooting ability. If the accuracy was only to a 10% degree then the beam would have to be the better choice. How much variation would be an acceptable result in this test.

And by the way - "hi all". I'm a relatively new shooter who has been doing some .22 target and 12g trap shooting for a couple of years. Put a deposit on my first centrefire last week - a LH Tikka T3 .222 - and am hoping to find a property do do some fox hunting in the near future. Enjoying the forum - very positive and knowledgeable.

[bigfellascott]

When I want to get fussy I drop a charge just under what I want with the chargemaster then finish of using he 505's (just trickle the last bit to get it spot on).

[Baldrick314]

When I want to get fussy I drop a charge just under what I want with the chargemaster then finish of using he 505's (just trickle the last bit to get it spot on).

I got the chargemaster to make reloading more convenient

The ideal outcome here would be if both lots of ammo shot the same size groups, then I'd fully trust the chargemaster and would use it full time. It definitely makes weighing charges a lot quicker I'm just worried about the accuracy of the weight

[Baldrick314]

This test is timely for me as I'm just getting set up to do some reloading in the future and trying to decide between digital scales/powder thrower and a balance beam scale. By my maths a 0.2g variation on a 20g load is actually 1% - so my question is - will a 1% variation in load make a significant difference - assuming constant shooting ability. If the accuracy was only to a 10% degree then the beam would have to be the better choice. How much variation would be an acceptable result in this test.

And by the way - "hi all". I'm a relatively new shooter who has been doing some .22 target and 12g trap shooting for a couple of years. Put a deposit on my first centrefire last week - a LH Tikka T3 .222 - and am hoping to find a property do do some fox hunting in the near future. Enjoying the forum - very positive and knowledgeable.

Welcome aboard . I've found the chargemaster really speeds up my loading time but I've been a little dubious of the accuracy of it's measurements. I don't know how much difference a potential variance of .2 grain will make in a 42 grain load in terms of difference in POI so the results will be interesting

[bigfellascott]

When I want to get fussy I drop a charge just under what I want with the chargemaster then finish of using he 505's (just trickle the last bit to get it spot on).

I got the chargemaster to make reloading more convenient

The ideal outcome here would be if both lots of ammo shot the same size groups, then I'd fully trust the chargemaster and would use it full time. It definitely makes weighing charges a lot quicker I'm just worried about the accuracy of the weight

You will get variation in the loads from the CM, I've tested them on the scales and most were slightly under or spot on. I only hunt so its not overly important to me if they are over/under by .1 or .2gn, but if I was shooting targets I'd do what I mentioned above to be more consistent.

[Apollo]

Sorry guys, got too many figures floating around in the noggin at present. 1% it is.

I've just been doing some test loads prior to a competition but my criteria is a little tighter to test 0.1gr either side of my standard accuracy charge of 37.4gr and I'm working with a Gempro 250 with an accuracy of 0.02gr which in my case with AR2208 is about one single grain of powder. My accuracy on the targets is 0.25" at 200 metres so I'm trying as accurately as possible to see which side of my normal load I can go to tighten accuracy or which way if any it gets worse.

I know mixing metric with imperial but accuracy I measure in MOA and the target distances are metric so basically trying to keep at 0.2 MOA or better but then other factors blow that out when you get to 500 metres with 5 shot groups and a breeze. Sub 1 1/2" groups would be nice and also competitive.

BTW... Great calibre .222R and very accurate if you put the time into testing. The mate loves his .222R Brno Fox 2 and has no problem hitting a Fox or Cat in the head at near 300 metres.

[Baldrick314]

Sorry guys, got too many figures floating around in the noggin at present. 1% it is.

I've just been doing some test loads prior to a competition but my criteria is a little tighter to test 0.1gr either side of my standard accuracy charge of 37.4gr and I'm working with a Gempro 250 with an accuracy of 0.02gr which in my case with AR2208 is about one single grain of powder. My accuracy on the targets is 0.25" at 200 metres so I'm trying as accurately as possible to see which side of my normal load I can go to tighten accuracy or which way if any it gets worse.

That's bloody accurate. What calibre do you shoot and what comp?

[Apollo]

They had want to be accurate, custom rifles cost a mint yet alone the optics. The comp coming up next week is 300 metre then 500m Benchrest. The 300m rifle is a custom built Remington 700 but it's only doing at best .260" groups at 200 metres, trouble is every now and again it keeps throwing a wild shot outside the group and that's what I'm trying to solve. Pretty sure it's not me as the main rifle, a Stolle is very consistant. Both have 1 1/2 oz Jewell Triggers but different Gunsmith's.

Calibre is 6.5x47 Lapua, 130gr Berger VLD's trimmed and pointed. All cases and bullets are weight sorted etc to the same standards.

I'm only learning and need much more practise especially after being out of action for around 6 months.

[tom604]

They had want to be accurate, custom rifles cost a mint yet alone the optics. The comp coming up next week is 300 metre then 500m Benchrest. The 300m rifle is a custom built Remington 700 but it's only doing at best .260" groups at 200 metres, trouble is every now and again it keeps throwing a wild shot outside the group and that's what I'm trying to solve. Pretty sure it's not me as the main rifle, a Stolle is very consistant. Both have 1 1/2 oz Jewell Triggers but different Gunsmith's.

Calibre is 6.5x47 Lapua, 130gr Berger VLD's trimmed and pointed. All cases and bullets are weight sorted etc to the same standards.

I'm only learning and need much more practise especially after being out of action for around 6 months.

do you weigh the cases, they can be different weight's ,,if your going to all that trouble for .1/.2 of a grain it would be a bugger if your cases were out by that much

[Baldrick314]

They had want to be accurate, custom rifles cost a mint yet alone the optics. The comp coming up next week is 300 metre then 500m Benchrest. The 300m rifle is a custom built Remington 700 but it's only doing at best .260" groups at 200 metres, trouble is every now and again it keeps throwing a wild shot outside the group and that's what I'm trying to solve. Pretty sure it's not me as the main rifle, a Stolle is very consistant. Both have 1 1/2 oz Jewell Triggers but different Gunsmith's.

Calibre is 6.5x47 Lapua, 130gr Berger VLD's trimmed and pointed. All cases and bullets are weight sorted etc to the same standards.

I'm only learning and need much more practise especially after being out of action for around 6 months.

I've thought about batching my cases by weight, what's your tolerance for a batch? Say the bulk of your brass weighed 96 grains and you had some that were 95.5 and some that were 96.5 would they all go to the same batch or would they be put into different batches?

[Lorgar]

I've got the Chargemaster as well. Interested to hear your results.

[Apollo]

Yes, I weigh cartridge cases and sort them into lots to the nearest 0.1gr in increasing order.

Firstly, lets go back to the Topic "Electronic Vs Mechanical (Beam Balance) Scales.

I have had and used a few different ordinary run of the mill electronic scales over the past years like Hornady, RCBS, Lyman etc and found them at best pretty ordinary and didn't qualify for their own standards like +/- 0.1gr accuracy especially over a period of time. All suffered from drift to varying degrees and inconsistantcy from day to day verified with a calibrated set of check weights. So, calibrate the scales with their own calibration weight, measure a check weight of say 20gr and it may measure correct or it may measure say 20.2gr so compensate by 0.2gr however come back a half hour or so later and measure the same weight and it will have changed to say 20.0gr or most likely 20.4gr or even 19.8gr but not the same as the starting point.

This error can be even worse but sometimes they will provide a reasonable say +/- 0.2gr for awhile then for no reason all of a sudden will show a much greater error so back to calibration again. Pain in the butt.

Mechanical Balance Beam Scales are generally more consistant but slower waiting for the beam to settle. There is more, you may zero the scales exactly and then set them for say a weight of 20gr but they may or may not show exactly 20gr with the 20gr check weight so you set them to show exactly 20gr and away you go. Generally they will show the correct weight from thence onwards until you bump something or change the settings.

Most Balance Beam Scales I have seen have Nylon/Teflon pivot points, RCBS, Lee, Lyman etc and I know for a fact over time they wear and will start to show errors as the beam knife edge bearing will sit in a different place. One exception I know to this is the Redding Model 2 Scales that have hardened metal inserts as their bearing points and are far more consistant over many years. In fact one set of these I have had since the early 1970's and are still very accurate.

Back to measuring cartridge cases.

I only weight batch quality match grade cases for target use, like Lapua Cases which are reasonably consistant in the first place. This is only done after I have completed my full case preparation on brand new cases in say a batch of 200 or more. First up is to Full Length Resize every case to get them all to the one standard size and whilst doing this I check every primer flash hole to ensure there is no burr or obstruction. I also ream every primer pocket to a set standard depth. Next is some length measurements and set the case trimmer to trim every case to an even length and then neck turning to at least even out slightly neck thickness. This could be just a very slight touch or a complete cut if they are going into a tight neck custom chamber. Then de-burr all case necks inside and out followed by a clean to remove sizing lube.

Now I'm ready to weight batch since all the cases should be the same dimensions.

I tried that with the cheaper electronic scales and they were too inconsistant, tried with the Redding Balance Beam Scales but it's very slow and can also be inconsistant in that the scale tray has to be in the exact same position and also the case has to be in the exact same position every time. If it's not the reading will vary a tiny amount.

So come the GemPro 250 Scientific Electronic Scales. Reasonably priced and available locally at around $175.00 and way more accurate with a resolution of 0.02gr, quick taking just a couple of seconds to resolve and if warmed up properly say for a half hour or so are mostly very stable and consistant. Much cheaper than some well know scientific scales at around a grand.

I then batch in increments of 0.1gr to the nearest 0.1gr..ie 0.04 goes down, 0.06 goes up. BTW, bullets are done the same. I then have a whole series of weight batches across the bench and they are put in order starting from the lightest to heaviest into ammo boxes and labeled. I reload and shoot them in order of increasing case weight, same applies to bullets.

Lapua cases are reasonably consistant but their can be the odd one or few out of the ordinary and these are put to one side for warmer / fouling loads. My recent batching of 6.5x47 Lapua cases I had the majority weigh from 157.4gr to 158.4gr over 200 cases with about a dozen funny weights which I have put aside. I do the same for my other target grade rifles which are 22BR, 6mmBR and 30BR.

I use Lapua cases also for my and a mates varminting rifles like .222R, .223R and .243W but I don't both weight sorting as it's too hard to keep them in order out in the field. I may weigh them to see if a few are something really strange and put them to one side but still in the same usage lot.

Another varmint calibre both my mate and I use is .204R and for that we use Nosler Brass which is actually Norma Brass but Nosler have fully prepared the cases and weight sorted them in large batches. It's expensive but very consistant with the accuracy from those cases compared to other brands like Hornady, Federal etc.

Wow, sorry what a long saga but there is still a lot more in the way of finer details producing match grade ammo.

I hope all this is of some help with the topic of comparing different scales. Mainly it's all about reducing flyers and consistancy of velocity shown when it comes to testing loads always using a Chrony and watching the ES & SD figures.

[Baldrick314]

Apollo,

Thanks for going so in depth. It made for interesting reading. I weighed the cases I have on hand and if I batched by .1 I'd end up with a ridiculous amount of batches with weird numbers of brass so I'm thinking I'd probably go by half grain. I'm shooting a completely stock rifle so I don't know how much it would actually help accuracy to batch my brass

[Apollo]

I would imagine you are using the likes of Winchester, Remington or what ever cases and this is what happens with ordinary type cases.

Not long ago I was given some 4-500 once fired Winchester .223R Cases picked up on a range. I have prepped basically a few hundred, no neck turning and these I'm going to do a basic weight sort. I expect as you have a wild variation in weight but when I find the time I'll have a go and see what sort of numbers I get. If I get a run of at least say 20 cases within 0.2gr I'll give them a trial as one batch and trial say the same number that aren't weight sorted to compare the same load, bullet etc.

The .223R I have and know is reasonably accurate, 0.5 MOA is a CZ 527 .223R Varmint, Single Set Trigger and a reasonably flat forend that will ride a front bag reasonably consistantly. The test will be with one of the match grade bullets I have like Berger, Nosler Custom Competition or Sierra Match Kings.

I wouldn't expect any improvement over the normal 0.5 MOA accuracy but I'd expect less unexplained flyers that spoil nice groups. It's all a bit of fun and more so good practise. In fact I'm just in the process of setting up the shooting bench outside, wind has dropped so I might spend the afternoon with the cases I have batched and loaded from last night. Mainly to check zero on a scope, varify ballistics and set the scope for the required range and save me some time sighting in at the actual range next week.

It's nice to be able to shoot at home and make quick adjustments. One advantage of living in the bush.

[Baldrick314]

Apollo,

You certainly have it lucky!

I'm using federal cases. My rifle usually holds half MOA and I do all my shooting off a bipod and rear sand bag.

See how the test goes this weekend, maybe next I can try cases batched by weight Vs unsorted

[Baldrick314]

Life got in the way today so I didn't get out to the range. Will have to try again next month

[Apollo]

Life didn't get in the way for me today. Was going to spend it running power cables around my 4WD to complete my dual extra batteries, second in the front, third in the back BUT.... the wind dropped, the sun came out so I went and grabbed two rifles, set up the targets and shooting bench to test loads and sight in for a shoot next weekend.

All went very well. The final loads I did with my Redding Balance Beam Scales then checked with my GemPro 250 worked out very well and I have two loads to use in the competition shoot.

Targets at 200 metres, 6.5x47 Lapua calibre both rifles. The custom Remington 700 shot a 0.35" 5 shot group and the custom Stolle Grizzly II shot a 0.25" 5 shot group. Velocity checked with the Crony and adjustments made to get them close at 300 metres and 500 metres respectively so now the next nice day will be a test at both distances.

Isn't it nice when the weather man comes to the party.

[Baldrick314]

Nice one . Yeah the weather even cleared up out here in the morning so I was a little miffed not to be going but it all feel apart not too long later so I don't think it would have been a great day for it anyway.

[Lorgar]

Life got in the way today so I didn't get out to the range. Will have to try again next month

Bugger. Well, still keen to hear in a month when you get to it

[Baldrick314]

I finally tested the loads made on both scales. The results are far from conclusive, mostly because my shooting isn't exactly up to scratch (haven't shot rifles for a couple months)



The loads made on the chargemaster are the two groups at the top and the bottom groups were loaded on my balance beam scales.

There's one very obvious flyer in one of the bottom groups but otherwise the groups were near enough to the same size. For my purposes I'm satisfied that I could load ammo on either scale and it would be equally accurate which is the best result I could hope for.

[Fry]

I didn't measure on the screen but looks like the top groups are just edging the bottom ones out on accuracy?

Marginally better?

[Baldrick314]

I didn't measure on the screen but looks like the top groups are just edging the bottom ones out on accuracy?

Marginally better?

The top left was the smallest group overall. Disregarding the flyer in the bottom right group the others are nearly identical in size so not much in it. I was expecting the balance beam to make much better ammunition but at the end of the day they're that close that it makes no difference

[Lorgar]

I was expecting the balance beam to make much better ammunition but at the end of the day they're that close that it makes no difference

I hate using the balance beam instead of my Chargemaster so that's good to read

[Baldrick314]

I hate using the balance beam instead of my Chargemaster so that's good to read

Yeah it halves my loading time so I'm happy with the results

[Lorgar]

I just loathed turning that *&^##&^ knob on the powder thrower and waiting for the balance mean to settle when changing powder charges.

It was a slice of heavy to change to the digital dispenser/scale and just type a number in