balance beam scale issue

[jlopez]

I have both the RCBS 505 and the Hornady model M balance scales. I have been utilizing the RCBS scale for approximately 10k rounds. I ended up with the the Hornady scale in an estate purchase of reloading equipment. I like the hornaday scale because the numbers are easier to read the tray does not build up any static electricity so when dumping a charge i do not have to keep tapping it. However when comparing this scale against the RCBS with some Clays powder for a 45 acp load of 3.8 grains the hornady reads 2/10ths of a grain lower (ie 3.6). I transfer the powder load from one tray to the next making sure all the powder transfers. I planned on switching to the hornady scale because I like just a little better and planned on selling the RCBS but now this has brought doubts into my mind of which one is actually correct of if both are mis-calibrated. With out having to buy a check weight system is there any other way to validate which one is correct. The hornady appears to have an adjustment via the nuts on one end of the balance beam however the RCBS does not appear to have any adjustment. I would not want to sell either of these until i have the peace of mind of them being calibrated.

Thank you in advance,
Juan

[HunterCO]

Have you checked the zero on both scales??

[Marlin]

Yeah, Check the zero.. then with a known weight,, Check both.

[jlopez]

Thank you all for answering,

I did check the zero on both as stated in the instruction manual. I do not have any check weights. I was trying to avoid them as the cheapest i found at midway was 23.99 which is a significant cost when you compare it against the cost of the scale.

I was given a suggestion on another board for finding an item such as nut or washer and having the pharmacy measure it for me so I have a very inexpensive check weight.

I am going to try this first. Again I appreciate your replies,
Juan

[Marlin]

You have some Bullets don't You? For the most part they should be within a few grains of what the are listed.. That should get You close enough..

[jlopez]

Marlin,

Yes I have some bullets. I have some hornady xtp 230 gr which weighs 229.7 on the rcbs an 229.4 on the hornaday. Not such a big deal when you are looking at these weights but when the load range is 3.6 to 4.3 2/10th can make a difference. I would have to say that I trust the rcbs as I have utilized for last 7 years and loaded several thousands of rounds. The person I planned on offering it to will be loading pistol cartridges also and I just want to make which one is correct.

thanks,
Juan

[Marlin]

Well, if Your close to My part of town,, I could offer My weights from My electronic scales,, That way You could check 'em..

[dmeis]

The RCBS is zeroed using the white wheel on the bottom of the scale. Spin it up or down...

Mine seems to be off for the lighter pistol loads. To combat this I throw 10 charges and adjust the powder measure for the average.

Sportsmans carries the RCBS check weights...

[jlopez]

Thank you to all for the replies. I finally broke down and bought the check weights today. Sportsman did have one set in stock along with some primers today. Just checked both scales. The RCBS was dead nuts on. This was the unit I was planning on selling to a friend that wants to get started reloading.

When I balance the Hornady with the check then they both read the same. I will hopefully be getting into some long range shooting this year so accuracy there is also paramount and I figured I could not go wrong with having them. I was just trying to avoid buying them as I would rather spend it on something else. Peace of mind though I think will be worth the 27.00 plus tax

Thanks again,
Juan