PUBLIC Forums => Public Forums => Technical Assistance => Topic started by: Nancy McCombs on September 29, 2017, 11:50:19 AM
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AFTE friends,
Can anyone assist me in identifying these metal objects.
The round pellets are ~26.8 grains and .297" in diameter, and the cylindrical pieces are ~43.3 grains, ~.241" in diameter, and ~.499" in length. They all have magnetic properties.
Six round pellets, five cylindrical pieces, a fired shotshell with a "WINCHESTER 12 GA" headstamp, and several paper and plastic wads (consist w/12GA) were also submitted.
The cylindrical pieces are very uniform in size and weight, so are likely to be commercially made. They do not look like wire shot.
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Both types have properties found in wheel bearings, among other bearings; originally, they would have been perfectly uniform. These appear to have been released from their carriers, called "races". (If that's what they, indeed, are). :)
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Thanks Bob,
Based on these images I found I think you may be right.
Thank you very much.
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When I first saw the pic I thought they were pressure "coppers" used to check striker energy or measure pressure in a chamber. The pressure chambers for artillery pieces have round balls (such as you picture) and the pressure vessel is submerged in the propellant and when the gun is fired you start looking for the gage which can be upwards of 60 yards from the muzzle all the way to still in the case.
But since you say they are magnetic they can't be copper so that rules them out.
(https://i.imgur.com/jz56PDch.jpg)
The above pic shows a "copper cylinder" inserted in "copper holder" for checking striker indents.
click on pictures and they will get larger to give more detail.
(https://i.imgur.com/ccdutVCh.jpg)
After the indent is made the "copper" is removed and inserted in a bench inspection gage and the depth of the indent is recorded. This shows .0185" indent which is more than SAAMI recommends but less than some vendors want for their internal standards. I prefer my indents at .020" depth or deeper.