PDA

View Full Version : Simple modification you can do to RCBS 10-10 scale for sorting bullets by weight.



VaniB
05-12-2013, 10:47 PM
..
..

Here is how our RCBS 10-10 scale looks as it comes from the factory;

http://imageshack.us/a/img818/3072/006ipg.jpg
..
..




This is the modification we want to make to the scale, so it will have graduation tick-marks that we can use for weighing bullets and sorting them by weight;
..
..
http://imageshack.us/a/img707/6322/018nmp.jpg
..
..

In order to sort bullets by weight, we will need to apply calibration markings to provide reference points. Fabricated from out of an inexpensive discount store plastic ruler, we will construct an add-on piece for this purpose that I will refer to as the "graph". The inexpensive plastic ruler with one side of it marked in millimeter measurement is a perfect source for such a graph, being that its closely situated tick-marks will indicate small fluctuations in weight.


Using an exacto knife, score the plastic ruler on both sides to cut out a 1 9/16" long section. You don't have to cut all the way through the ruler, as once you have scored it on both sides, the small portion can be easily snapped off cleanly. Then using the sharp blade edge, scratch off and remove the printed numerals on this small plastic piece. It's the tick-mark graduations that you will be needing on this graph piece and not any of the ruler's printed numbers. At this time you can continue to make a couple of more cuts and shape this small plastic piece to about a 1/2" width at both ends and just big enough to mask and cover the scale's indicator face. Using an emery board or a file, slowly and carefully sand away about a 1/16" or less from both ends of this small plastic piece a little at a time until it fits snug and snaps into place on the 10-10 scale aluminum bracket. If you sand off too much so that it will not snap and hold firmly in place, then simply secure the graph to the scale with a light dab of rubber cement. Lastly, use scissors to cut a small triangular arrow-like indicator shape out of a piece of cardboard or paper or an old credit card. Use a magic-marker to color it black, and then glue it to the graph. This arrow shape will serve as an instant point of reference which the eye can spot faster and easier.

..
..
http://imageshack.us/a/img24/4135/007hps.jpg


An egg carton makes a handy organizer with enough small compartments so that the bullets or cases can be weighed and neatly sorted. It just happens to turn out that each tick-mark on the graph closely relates to 1/10 of a grain. It is my preference to weigh and sort bullets to within about a half of that 1/10 of a grain measurement so that the -1/2 or + 1/2 compartments you see in the egg carton are useful for when the beam points at a spot midway between any two tick-marks.

Egg carton;
http://imageshack.us/a/img211/6039/019ht.jpg


The 10-10 scale that you see in the photo was purchased back in the 1970's. Frankly, I don't know why RCBS to this day has not seen fit to modernize the design and ad these kind of calibration markings straight from the factory. It's not only handy for sorting bullets by weight, but it very useful during the standard duties of measuring powder charges. I think most of you guys will find this to be a very simple but useful feature to apply to your scale.

alinwa
05-13-2013, 12:18 AM
Nicely Done!! And an awesome pictorial :)

Thank you for a clear, informative post.

al

Boyd Allen
05-13-2013, 10:31 AM
It doesn't get much better than a how to do it, with good pictures. Thanks

abintx
05-13-2013, 09:55 PM
If you have to sort bullets by weight you're shooting the wrong brand of bullets. Purchase them here instead: http://www.rcheek.com/ and http://www.bartsbullets.com/ :)

adamsgt
05-14-2013, 11:56 AM
..

10-10 scale that you see in the photo was purchased back in the 1970's. Frankly, I don't know why RCBS to this day has not seen fit to modernize the design and ad these kind of calibration markings straight from the factory. It's not only handy for sorting bullets by weight, but it very useful during the standard duties of measuring powder charges. I think most of you guys will find this to be a very simple but useful feature to apply to your scale.


Interesting, I have an Ohaus 5-0-5 beam scale that is at least as old as your RCBS and it has the index marks you're adding. It does make you wonder.

Joe Maisto
05-14-2013, 03:14 PM
Interesting, I have an Ohaus 5-0-5 beam scale that is at least as old as your RCBS and it has the index marks you're adding. It does make you wonder.

And I too recently sold my Pacific that goes back to the 60's with the calibrations already installed, and with an oil dampener as well...to slow down the swing of the beam.

Roy Allain
05-15-2013, 01:53 PM
And I too recently sold my Pacific that goes back to the 60's with the calibrations already installed, and with an oil dampener as well...to slow down the swing of the beam.

I have a Lyman Ohaus scale which my wife gave me for our 1st wedding anniversary in Oct. 1966. The price was $12.56 and is written in pencil on the box which I still have. The scale is magnetic damped. Very accurate, still and it has a graduated vertical scale. Go figure. $12.56. Nice.

Roy