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What a properly detonated looks like M67

SLAP_

Active Member
Since we usually only get to see low-order M67s...

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Assembly set for advanced collectors. (Image source: http://www.dtic.mil/dtic/tr/fulltext/u2/a500888.pdf)

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This picture shows almost proper fragmentation. Desirably each blunt cone should form a single fragment with an irregular jagged base, roughly 2...3 mm in diameter and an average weight of around 100 miligrams to ensure a high hit probability. Note the distance between each line is 1 mm (Image source: https://projects.nfstc.org/trace/2011/presentations/Flohr-Different-Kind.pdf)

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Mini arena test (with an open top) to collect the fragments from an M67. This test set-up was used if a a new detonator would suffice to high order detonate an M67. (Image source: https://ndiastorage.blob.core.usgovcloudapi.net/ndia/2008/fuze/VACheng.pdf)

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Dents caused by the high velocity fragments in the heavy gauge aluminium(?) sheets. (Image source: https://ndiastorage.blob.core.usgovcloudapi.net/ndia/2008/fuze/VACheng.pdf)

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1312 fragments were collected from the M67 with a standard C70 detonator. Since there was no roof installed we need to calculate the total amount of fragments: (1312/5)*6 = 1574,4. (Image source: https://ndiastorage.blob.core.usgovcloudapi.net/ndia/2008/fuze/VACheng.pdf)

The M67 body w/o explosive weighs around 170g. That gives us 170g/0.1g = 1700 fragments nominally.

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Fragmentation pattern of a M42/M46 Grenade Body (submunition). The M67 uses the same type of pattern to ensure correct fragment size and mass.

Edit: I have screwed up the thread title.
 
Nice to see the results of what the intended piece of ordnance is meant to do. There are documents on S-Mine fragmentation in the archives which show similar outcome.
 
Interesting to see a distinct pattern in the dents. Certainly not a random fragmentation. Impressive.
 
SLAP.-, do you know if they are still using pinewood spaced at different distances and in the form of a circle around the grenade in order to tell what the frag pattern looks like at distance(s)?
 
If you are asking for the M67 specifically, I don't know. I haven't seen any documentation on the M67's performance beyond that what I have posted already.

As for arena testing in general they've always used different kinds of materials to assess the spatial distribution of fragments. I've seen documents with paper, steel sheet metal, aluminium sheet metal, rolled homogeneous armor, plywood etc. If you are just looking for spatial distribution of fragments about any material will do that will have a visible mark after fragment impact. If you want to assess effectiveness they sometimes use a more elaborate sandwich type construction or sheet metal of a certain type and thickness.

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Anything goes. https://ndiastorage.blob.core.usgovcloudapi.net/ndia/2012/IMEM/13825widener7A.pdf
 
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