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Re: Rotometals Reclaimed Shot

Posted: Fri Sep 25, 2015 5:30 pm
by mtngun
A chemist friend (Glen Fryxell) advised me that, if money were not an object, this is what he would do:
XRF is very accurate, but will only tell you what's in the surface (about top 5=10 nm or so). For bulk composition, I would dissolve the sample in acid and run an ICP-MS or ICP-AES on it. Flame AA is also good (but somewhat dated).

Galbraith Labs in Knoxville, TN does a lot of analytical testing. We've worked with them in the past and they are good, and turnaround is prompt.

Galbraith doesn't list prices on their website but whatever it is, I can't afford it. :lol: So I guess this is the end of the road for my quest to figure out what makes this batch of reclaimed shot special. :cry:

Re: Rotometals Reclaimed Shot

Posted: Sat Oct 10, 2015 11:39 am
by mtngun
Measuring the indentation after 1 month of aging with a USB microscope. The calipers were locked on 0.080", 7.9375 mm ball (5/16" diameter), 150.6 kg load for applied for 30 seconds. 46 BHN. :o

Now whether it shoots any better than a less hard alloy, I don't know. Much testing will be required to answer that question.
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Re: Rotometals Reclaimed Shot

Posted: Fri Apr 22, 2016 2:43 pm
by mtngun
I acquired some more reclaimed shot, but this time from J.R. SHOT LLC on ebay (jrshot@att.net).

This was clean shot that looked like new other than being dinged. Unlike the dirty Rotometals shot, this stuff was easy to smelt.
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Density = 2768 grains/c.i., vs. 2719 gr/c.i. for Rotometals shot.

So right off the bat we know it does not have exactly the same chemical composition as the Rotometals shot. I'm bummed, but that was to be expected for a recycled product.

Air-cooled BHN = 13, vs. 15 for Rotometals shot.

Oven treated @470F = 34 BHN after 16 hours, vs. 40 BHN for Rotometals shot.
After 10 months = 32.6 BHN

SUMMARY: the "J.R." shot is better (harder) than clip-on wheelweight, but not as hard as my sample of Rotometals reclaimed shot.

Re: Rotometals Reclaimed Shot

Posted: Wed Jun 01, 2016 11:26 am
by mtngun
Since my first batch of Rotometals reclaimed shot was good stuff, I bought some more. Well, the second batch looked different than the first batch. Density and hardness are different, too.

Density, and other alloys for comparison:
Batch #2 Roto Reclaimed Shot = 2768 grains per cubic inch
Batch #1 Roto Reclaimed Shot = 2719
J.R. Reclaimed Shot = 2768

Hardness
Air-cooled = 10 BHN
One day after quenched @470F = 41 BHN !

Wow! :o I was surprised it heat treated to 41 BHN despite being only 10 BHN air-cooled.