RCBS Chargemaster scale accuracy concerns

[USAFRet]

I bought an RCBS Chargemaster a while back. It has seemed to be accurate so far when I double check loads.

Loaded 20 rounds of 6.5 CR test ammo tonight. The scale weight seemed to be jumpy and when I was double checking my loads on my Franklin digital scale, I was catching it being sometimes .3 - .4 grains off in measurement. I recalibrated several times and it seemed like it would clear up for a few loads and then would start doing it again. By the time I finished up, it was doing it on every load. It's like it would not steady out and a couple of times when I tried to zero, the pan measurement was jumping all over the place with up to .5 grains difference.

My pan weighs 126.2 and when I would start to put it on to zero, it seems the numbers would never settle, although ti showed stable. Now I don't trust the ammo I loaded to have the same grain measurement. I hate wasting components. Almost makes me want to go back to manual measurements with the tower charger and hand trickler.

Anyone have this issue?

 

[Homerange]

Some have issues under fluorescent lighting apparently.
When I researched them some years back it seemed good practice to make some mods to them and one was placing toroid rings on the lead with a few wraps which absorbs any crap on the power lead that might influence readings.

 

[R.Morehouse]

Tripp Lite makes line conditioners at varied price points. That is what I used when I was using an FX120. I think if I was using a Chargemaster I would set it up to be battery-powered. That would allow you to bring it to the range for load development or load between relays at matches.

Regards
Rick

 

[rocketron]

It could just be static. Wipe all of it down with a dryer sheet or static guard spray.

 

[M-61]

Never had a problem with mine, and never made any modifications. Followed the instructions exactly from day one.
This is my experience with my Charge-master and not what I heard somewhere.

 

[LHSmith]

Could be a problem with drafts in the room- try shielding the unit from air currents. Heating season is the worst for me to keep zero.

 

[jimmymac]

I've never had that much deviation. Not even close. Try eliminating the AC to DC power converter completely and go with a 12V battery to see if that helps. Also, how do you know the Frankford Arsenal scale isn't the problem?

 

[robert8904]

I had jumpy readings on my new Chargemaster Lite. I believe it was static electricity. A dryer sheet helped but what really fixed it was raising the humidity. In cool, dry weather I heat a big pot of water which absolutely solved the problem since I live in a small condo.

 

[CharlieNC]

In addition to dry winter static on the gear, be sure your personal self is grounded. No rubber sole slippers or shoes, I load barefooted (yes I'm a redneck).

 

[rayporter]

my chargemaster started doing this same thing last week. i found i had a bug in the system. actually a ladybug or beetle had died under the platen. picked out the bug and it worked fine.

 

[marchx]

I bought an RCBS Chargemaster a while back. It has seemed to be accurate so far when I double check loads.

Loaded 20 rounds of 6.5 CR test ammo tonight. The scale weight seemed to be jumpy and when I was double checking my loads on my Franklin digital scale, I was catching it being sometimes .3 - .4 grains off in measurement. I recalibrated several times and it seemed like it would clear up for a few loads and then would start doing it again. By the time I finished up, it was doing it on every load. It's like it would not steady out and a couple of times when I tried to zero, the pan measurement was jumping all over the place with up to .5 grains difference.

My pan weighs 126.2 and when I would start to put it on to zero, it seems the numbers would never settle, although ti showed stable. Now I don't trust the ammo I loaded to have the same grain measurement. I hate wasting components. Almost makes me want to go back to manual measurements with the tower charger and hand trickler.

Anyone have this issue?

Yes. Welcome to the club. Recheck every charge with a second precise scale.

 

[DiRTY DOG]

My Chargemaster Supreme did the same thing this week, the 131.2gr pan read 0.2 to 0.5gr heavy. And it overthrew time after time. Tried repeated calibrations, restarting, and rubbing everything down with a dryer sheet. It eventually calmed down after about 50 throws over an hour and weighed correctly.

I think it was related to the recent cold dry weather? Never had this issue with it before, nor with the Chargemaster 1500 for ten years before that.

 

[wkdickinson]

I've had an RCBS Chargemaster 1500 for about 7-8 years. I have never been confident in it actually performing to the +/- .1 gr it supposedly is capable of. But it is still way more accurate than "throwing" charges. I run my power through a Monster power conditioning strip, then through a battery and I have changed all of my lighting to LED. After having done all that, when checked against my GemPro 500 it usually will be within +/-.15-.2.

About a month ago I decided to purchase an AutoTrickler V4. I got the A&D FX120i scale within a week, but am still waiting on the AutoTrickler. So shortly after I got the scale I ran a test of 50 throws from the CM 1500, weighed on the 120i. Surprisingly, I found them to be consistently within the +/-.15 range.

Last week I decided to load some 6.5 CM ammo. I fired up the CM 1500 and let it warm up for about 30 minutes. After calibrating I noticed the powder pan I dispense into weighted 139.8gr. It normally weighs 138.4 gr. I recalibrated 4-5 times, which did not help. I rebooted the machine several times, again the pan still weighed 139.8 (I did check it on my 120i and it weighed 138.4 gr like always). No mater what I did I could not get the CM scale calibrated.

So I went out on the net and did some research. One thing I came across was the possibility of powder being down inside the scale. In the time I've owned the CM I haver never taken it apart to clean it, so I did, and sure enough there was powder in the area of the loadcell, not a lot, but some. I blew it all out and put it back together. The powder pan then weighed 138.4 gr. Problem solved.

 

[Rocketvapor]

A second scale can be used with little more delay and as a confidence check.
I had a few rounds at a previous range trip that had an exceptionally low velocity. About 100 to 200fps below the average.

Traced it back to powder loss using a plastic funnel to charge cases.
Just not a good fit for .223 or 22 Nosler necks.
Ordered a 22 specific funnel to fix the issue.
Even had to smooth the joint between brass and aluminum as it wouldn't catch a kernel or two of SB 6.5 (a fine ball powder)

Using my primary scale I would toss and trickle the charge.
At the same time I would tare and weigh a case on the check scale.
Funnel the charge into the case and check the charge.
Tare next case, toss a charge, funnel into case, check charge.
Set case into loading block with an inverted projectile.
Sounds more difficult than it really is.
Stopped using the second scale now that I found the issue.

In this picture the main scale was in gram mode, the check scale was in grain mode.

 

[USAFRet]

Some have issues under fluorescent lighting apparently.
When I researched them some years back it seemed good practice to make some mods to them and one was placing toroid rings on the lead with a few wraps which absorbs any crap on the power lead that might influence readings.

I did have an LED lamp on. I wonder if that could have caused an issue.

 

[USAFRet]

Thank you for all the inputs. I did check to see if I had powder where the scale is, but may need to break it down and do a thorough cleaning. Will try without using the LED lamp and run the dryer sheet over everything. I did loads about .2 grains apart to do node testing, but don't trust the loads very much. I double checked a few times and thought things calmed down and then it would do it again. I don;t think anything is over .3 - .5 grains off, but when node testing that can make some problems.

 

[LHSmith]

Thank you for all the inputs. I did check to see if I had powder where the scale is, but may need to break it down and do a thorough cleaning. Will try without using the LED lamp and run the dryer sheet over everything. I did loads about .2 grains apart to do node testing, but don't trust the loads very much. I double checked a few times and thought things calmed down and then it would do it again. I don;t think anything is over .3 - .5 grains off, but when node testing that can make some problems.

0.2 gr apart is a bit over-kill. I favor 0.4/0.5 gr.

 

[M-61]

but may need to break it down and do a thorough cleaning.

Can you explain what you are breaking down?

 

[USAFRet]

0.2 gr apart is a bit over-kill. I favor 0.4/0.5 gr.

I am doing this node thing that was suggested. Find a node of three shots over a 2 grain spread where the numbers are the closest. I just started reloading recently and have done several different types of testing to find loads and literally feel like I have done nothing so far aside wasting components. This may be a waste as well.

 

[USAFRet]

Can you explain what you are breaking down?

Taking it apart to clean per the instructions, I guess.