Tip for RCBS Chargemaster Users

[Ledd Slinger]

My big problem with the Chargemaster is dealing with the tare weight. It is continually changing and must be zeroed from time to time.

When I called RCBS, they told me it did not matter and did not affect the accuracy of the scale. True the scale still reads zero when the tare drops a few tenths grain, but if it goes down more than that, the scale does not measure correctly.

I had that same issue with the rangemaster 750 years ago. Luckily both of my CMs hold zero very well. Best to leave them on for a while before loading. The new CM I have needs some warm up time. My other original CM doesn't require any warm up to hold zero.

My FX-120i also requires a decent warm up period before I can trust it

 

[Rick300]

And the parameter changes didn’t seem to work that well, either, so I set them back to the factory settings.

When I changed mine, I set it to the settings found online and found it was too aggressive. I ended up pretty close to factory, but you can change the step points for different powders which works really well.

 

[Ledd Slinger]

There definitely seems to be some differences from machine to machine with the CMs.

At least RCBS made them so they can be fine tuned so good on them for that. I suppose everyone just needs to test their CM and play with settings until they find the sweet spot.

I performed the straw and programming mods on my first CM exactly as per the 8541 Tactical video on YouTube and it has worked perfectly with every type of powder without ever throwing a single charge over target weight.

 

[Ledd Slinger]

So I made a video on my YouTube channel to show the accuracy of my original CM. Many people do not believe me when I tell them how accurate it actually is. The video explains the very simple mods I did to the CM and verifies a few charges thrown and cross checked on the FX-120i. Maybe not any new information, but it shows how accurate the CM "can" be when tuned. Your CM may require a little bit different settings in the parameters, but you should be able to get it where it never overthrows charges and weights are accurate.

Heres my video:

 

[Targetbanger]

The chargemaster only has a resolution of .1 grains, can't do .05

Ok thanks. So need to dig into. I'll just keep loading how I am then. Thanks again!

 

[Tommie]

So I made a video on my YouTube channel to show the accuracy of my original CM. Many people do not believe me when I tell them how accurate it actually is. The video explains the very simple mods I did to the CM and verifies a few charges thrown and cross checked on the FX-120i. Maybe not any new information, but it shows how accurate the CM "can" be when tuned. Your CM may require a little bit different settings in the parameters, but you should be able to get it where it never overthrows charges and weights are accurate.

Heres my video:

Thanks for making and posting that video. Eye-opening (for me, at least). Please let us know if your new machine performs equally.

 

[Ledd Slinger]

Thanks for making and posting that video. Eye-opening (for me, at least). Please let us know if your new machine performs equally.

Will do. I hope it works just as well. No hiccups with the few charges thrown after modifications, but it hasn't proven itself by any means yet. I'll do a bunch of throwing and charge weight cross checking with it aga8nst my FX-120i when I get back from my elk archery hunting trip next week.

 

[corsair4360]

I have a Chargemaster and have had it for 5 years or so. I did the programming mods suggested by others they help. The biggest change in mine has been to put it on an isloated circuit and put a charge stabilizing weight in the line after the DC like many devices used to use. I used mine yesterday and my 0.01 grain scale and the Chargemaster about 50% of the time had the charge down right on the money to 0.01 grains

 

[Ol’ Ed]

I have a Chargemaster and have had it for 5 years or so. I did the programming mods suggested by others they help. The biggest change in mine has been to put it on an isloated circuit and put a charge stabilizing weight in the line after the DC like many devices used to use. I used mine yesterday and my 0.01 grain scale and the Chargemaster about 50% of the time had the charge down right on the money to 0.01 grains

“Charge stabilizing weight”? I’m not following what you mean.

 

[boltfluter]

Ledd,

Great video! Your machine is amazingly accurate. You lucky dog! We expect nothing less than one shot kills all season!

Paul

 

[Ledd Slinger]

Ledd,

Great video! Your machine is amazingly accurate. You lucky dog! We expect nothing less than one shot kills all season!

Paul

Well now that s a whole different story. My rifles might be accurate, that doesnt mean I am! Lol.

 

[corsair4360]

“Charge stabilizing weight”? I’m not following what you mean.

I am talking about the device on the low voltage input line to the chargemaster in the attached picture. "A line filter is the kind of electronic filter that is placed between an electronic equipment and a line external to it, to attenuate conducted radio frequencies -- RFI, also known as electromagnetic interference -- between the line and the equipment." from wikipedia. I also leave mine powered up 99% of the time.

 

[mike a]

Aside from the straw is there a mod for the CM Lite? Mike

 

[powderbrake]

I was using my Chargemaster for benchrest reloading between target changes, and found it to be erratic and too slow. I suspected it was not level, as all the reloading tables at the range seem to have a slope to them.
I purchased a circular bubble level on amazon, and added it to the Chargemaster. This helped a LOT! When level, it does not underthrow or overthrow as often, and it completes a charge must faster.

I am not disputing Ledd Slingers technique of having the rear higher, as I have tried adjusting parameters, and have come back to factory specs. I also use the straw, cut with the large teeth like RustyNutZ48 in post # 18. This allows just one or a couple of kernels to drop at a time. I do not reduce the opening for the powder in the rear, as I am interested in speed. I am sure if you restrict the opening, you could get it to the point where it will drop one kernel at a time, but I am interested is speed, and will add or subtract a few kernels to hit weight if I have to.