How do you check a scales accuracy without check weights?

[jmak]

I purchased a used RCBS 505 scale a while back and wanted to know if there is a way to check the accuracy for 10 -15 grains of powder? I know they sell check weights but I don't really want to spend $25.00 to get a set. It is the only scale I own.

Thanks,
jmak

 

[sourdough44]

Check it with a lightweight bullet of a known weight. A 45-50 grain 22 bullet will do.

 

[pvtschultz]

Maybe you could get a jewler or someone with a delicate scale to weigh something for you that is in the neighborhood of what you are looking for and convert it to grains.

 

[Arisin' Wind]

Use coins. They have set weights.

A nickle weighs 5 gms.

 

[sixshot]

Weigh some pennies, they are very close to 38.58 grains, you'll be surprised.

Dick

 

[dg101win]

I always found that Sierra Bullets are within a few 1/10ths of published weight.

 

[jmak]

I looked at using coins but ended up getting a good deal on some check weights (grams) on ebay, $18.00 shipped.

http://cgi.ebay.com/PRECISION-SCALE-...item3c9b04b486

Thanks,
jmak

 

[GP100man]

Good deal on the check weights !!!

A peice of note book paper cut on the lines, squared weighs .1 gr.

 

[Rick Courtright]

Hi,

Ok, guys, throw rocks (of whatever weight) at me if you wish for saying this, but here's what an old timer told me early in my reloading adventures:

"If you can't afford a set of check weights, you can't afford to reload!"

I 'spose one could interpret that at least a couple of ways.

All I can say for sure is even though I ignored his advice for quite a few years before getting a set, mine have cost me an average of under $1/yr so far (or as low as 2 cents per use back when I loaded, AND checked the scale, weekly!), and as long as gravity keeps working, so will they. Which makes their amortized cost continue to go down...

In time, they've become one of the least expensive pieces of equipment I have, so maybe the ol' boy was right!

Rick C

 

[sceva]

get some steel balls ( from bearings ) of various diameters. Carbon steel of the various alloys has a fairly consistent weight of 0.283 - 0.284 pound / cubic inch per the Machinist handbook. There was also an article to this effect in the Sept - Oct 1986 Handloader magazine that used the ratio od 1,974 grain per cubic inch. There is a chart there for various sized balls.
I calculated the theoretical weight in grains for various sized steel balls then checked my Redding powder scale with them. Worked well.

.09375 ball = 0.851649 grains calculated

.125 ball = 2.019402 grains calculated

.1875 ball = 6.813192 grains calculated

.250 ball = 16.14979 grains calculated

.3125 ball = 31.54255 grains calculated

.375 ball = 54.50553 grains calculated

.500 ball = 129.1983 grains calculated

I hope this helped

 

[WESHOOT2]

I'm sorry; $25 for check weight set (I use the Lyman) is like wearing safety glasses and ear protection when shooting: Mandatory.