My reloading has been compromised

[Rocketvapor]

The Chargemaster scale may have a issue with slowly trickled powder, a loss of scale sensitivity.
(static and other issues can cause this)
You can check for loss of sensitivity by dispensing a charge, record weight, lift pan and reweigh.

 

[muleystalker]

Coyote, What you said startled me. So i looked at Hodgdon's site like you said and there is no mention of using WIN 760 with a 168 grain bullet, in fact the only WIN powder mentioned for 308 was Staball match. But if I looked up 260 Remington there is data for 760, and also for 30-06 with a 168 grain bullet. I also looked in one of Hodgdon's annual manuals, i have one for 2018 and it doesn't list 760 for 308 WIN either. I never invent a load and this came from listed data at the time is started developing it. I imagine they get more money for Staball match and remove WIN 760 data so as to sell the more expensive powder. The rifle is a Ruger 308 VT and has never shot very well but did OK with this mild load of WIN 760. I would match it against anything for a cold bore shot, always dead in the middle at 100yds. but it usually doesn't take very many more shots to be ugly. But 2 weeks ago it shot 3 that were in a group that was small and and 2 in another group that was one hole. And some times that can be fixed.

Hodgdons does list .308Win load with W760 for a 165gr bullet, starting load 48.0 grs, max load 51.0grs.

 

[hoz53]

I owned and used a Chargemaster and used a check weight. I then bought an AD FX 120i scale and started checking every weight thrown by the Chargemaster on the 120i and it was enlightening.

The Chargemaster does not throw charges with a high degree of accuracy. If the CM was set to 44.5, then 10 charges that all show 44.5 on the CM could be off by as much as +/- 0.5 grains when weighed on the 120i.

The scale in the CM is not very accurate. It will state that the target weight has been reached but the actual weight of the thrown charge can be different from the target weight.

In many cases the difference is small enough to where it does not matter, but if preciseness is desired, the CM does not do the best of jobs

Yeah — this is what i know about chargemasters also. Good Info — hopefully OP takes it to heart.

 

[mullmann]

I have a chargemaster lite and it works for me, but if you are a person who tries to get down to the last .1 grain for load development it’s not for you. I have pulled bullets for various reasons and checked the powder charge. A couple times the weights have been off by as much as .2 grains from when I originally loaded.

Now when I get done dropping powder in cases I will grab a couple cases from the loading block and double check them.

My groups are still fine so I don’t won’t worry about it. I also don’t shoot max loads so I am not going to lose sleep if I am off by .1 or .2 grains once in a while.

 

[Kracken McGraw]

To look at it another way, I have been loading a lot lately for 223 with Xterminator. Throwing out of a Uniflow and weighing on a FX120i. To make it easier on trickling I let it go to a .04 grain difference on loads, any charge variance’s bigger than that seems alarming on this scale.

 

[drop_point]

I've found the Chargemaster to be an excellent electronic thrower. I've measured mine against an FX120i and it throws within 0.2 gr consistently. I do have mine plugged into clean power, no vents in the room, and I use anti-static wipes on it when I use it.

 

[bks22345]

The Chargemaster does not throw charges with a high degree of accuracy. If the CM was set to 44.5, then 10 charges that all show 44.5 on the CM could be off by as much as +/- 0.5 grains when weighed on the 120i.

.5 or .05? I have a hard time believing 1/2 grain. I’ve questioned my CM from time to time and I have another RCBS scale that sits beside my CM that I use to double check. Sure there is a .1 grain difference from time to time (which one is wrong???) but I’ve never seen 1/2 grain.

To the OP, Lyman sells a little box of calibration weights for checking. I think they are .5,1,2,5,10 and 20 grains.

FYI I’ve also read you’re also supposed to let the scales warm up for 15 minutes before calibrating.

 

[RED DIRT]

I fell deep in the rabbit hole and bought a fancy digital electronic scale. It really looks great taking up space on the shelf above my bench in my reloading room. The fancy digital electronic scales are to inconsistent for me. I`ve tried a couple different higher end brands. Went back to my ole Redding Bench Rest powder measurer, Ohaus 10-10 beam, my ole Redding powder trickler and never looked back at techy electronic scales again.

 

[Bill K]

When you poured the powder out of case did you tap and/or even insert a swab to make sure all the powder grains came out. Old reloads sitting can have grains stick inside and that could vary your showing of weights. Just a thought.

 

[JLT]

Another contributor to the observed differences may be moisture content of the powder. Smokeless powder is hydrophilic to varying degrees. It is possible the cartridges were loaded under absolute humidity conditions different from the conditions of measurement.

 

[Coyotefurharvester]

168 gr 260R or 3006 data is not relevant to your 308 load data. The 165 gr 308w data is useful for load development.

 

[DiffEQ]

I had a charge master, it was a P.O.S.
Inconsistent, sensitive to temperature and finicky. It often threw charges 0.5 under to 2.0gr over setpoint. Even with the McD's straw hack, it still sucked. I gave it away.
I bought a lab scale (not a FX120i) and a set of check weights that go up to 200gr. I have much greater faith and accuracy in my loads now.

 

[ebb]

I get that coyote, my point is that for some reason they have excluded 308 win loads. Everyone keeps saying Hodgdon has a 308 load but last night at the data center there is not a load for 308 using WIN 760.

 

[drop_point]

Another contributor to the observed differences may be moisture content of the powder. Smokeless powder is hydrophilic to varying degrees. It is possible the cartridges were loaded under absolute humidity conditions different from the conditions of measurement.

I started to bring this up, but it will be hard to measure at this point for his individual situation.

 

[JLT]

I started to bring this up, but it will be hard to measure at this point for his individual situation.

Agreed. The degree to which moisture contributes to the differences observed by the OP cannot be measured precisely, but I'd hate to spend time trying to fix a powder dispenser that's not broken.

Some powders are better sponges than others. I've heard it said that a charge of LT-32 placed on an FX-quality scale on a humid day will absorb moisture quickly enough to watch the display drift upward. I've observed this myself. I use a Mettler-Toledo analytical balance (.0001-gram resolution) when I'm not in a hurry, and I've weighed the first and last charges on the loading block at the end of a session, noting differences substantially outside of my tolerances for the powder being used. It is not the balance - this thing is a rock-solid lab grade balance. It's moisture.

 

[jelenko]

hate to spend time trying to fix a powder dispenser that's not broken.

Just to this point, OP get some check weights - or use bullets/pennies as Rocketvapor mentioned.

 

[J_idaho]

OK I am kinda poor at keeping records and cannot find proof positive, but I am really sure my load for a 308win that I own is 41 grains of win 760. But its been a while and i cannot find it in my load book. So I pulled the bullets on a few and weighed the powder charge. One was 40.6 and the other was 39.9+ almost 40. the charge came from a very old Chargemaster that has been well taken care of and never given me any doubt till now. I follow the RCBS calibration sequence every time I turn it on and if I take a break for dinner or something unexpected, I recalibrate it again before I start up. When i first got it I checked it constantly and it was always right on, now i am unsure if it has gone bad or not. I got out my best RCBS balance beam scale and will go to Scott Monday morning. What do I do about the Charge Master? I don't know if I can reload without it. What do i do to make sure it gives out a consistent charge weight? Ive heard of the CMs dyeing, but this works as good as new. Has it always thrown way off and I never knew, or has it deteriorated with age?

I’ve owned the chargemaster lite for awhile. You shouldn’t give up on it.
1. It needs to be in a moderately warm constant temperature.
2. Weigh your dump tray, write that number with sharpie on tray.
3. Every time you pull a charge off scale verify negative number is same as number you wrote on tray.
4. If accuracy isn’t what you want it’s probably because there’s some air flow from a heater vent or something moving air around.
5. Use something like a straw to sleeve powder dispenser to smooth out clumps and stop big piles of powder from dispensing. This will slow it down a little but it’s better than spending a $1000.00 on a scale.
6. To verify run 10 loads and dump them into a separate container and weigh total weight this will add all those small variations that the scale cannot weigh in a single charge.

 

[DLT]

It appears that I don't own a known accurate scale, if the chargemaster is not. Just hope S Parker can get me back in business. The scale going to him is better than the one I used before the chargemaster so I will look up the one I used back in the day. It's around here somewhere in the factory box. Rocket vapor it comes with 2 weights that are marked 50g they are what was designed to calibrate the scale. To be honest I do not know if they are grains or grams now that you have asked me to think about it.

He can as long as in the right mood. Many good experiences with him on this site but it’s not without a fair share of hiccups.

 

[BigBolt]

I have a beam scale calibrated to .1 grain. Many years ago, I bought calibration weights ranging from .1 to 200 grains. My beam scale has been my back up for about 15 years when I switched to electronic scale. I check the scale about every 10th load with calibration weights.

 

[Lone Hunter]

OK I am kinda poor at keeping records and cannot find proof positive, but I am really sure my load for a 308win that I own is 41 grains of win 760. But its been a while and i cannot find it in my load book. So I pulled the bullets on a few and weighed the powder charge. One was 40.6 and the other was 39.9+ almost 40. the charge came from a very old Chargemaster that has been well taken care of and never given me any doubt till now. I follow the RCBS calibration sequence every time I turn it on and if I take a break for dinner or something unexpected, I recalibrate it again before I start up. When i first got it I checked it constantly and it was always right on, now i am unsure if it has gone bad or not. I got out my best RCBS balance beam scale and will go to Scott Monday morning. What do I do about the Charge Master? I don't know if I can reload without it. What do i do to make sure it gives out a consistent charge weight? Ive heard of the CMs dyeing, but this works as good as new. Has it always thrown way off and I never knew, or has it deteriorated with age?

This Data is from HORNADY 26 Edition
Next Data is from SIERRAS 50th Anniversary Edition. It shows 760 powder with 165 gr in .308 Winchester. Now, These are older books but I loaded out of them for years and they have produced accurate loads. Hopefully it will help you.