TM9-1901 says the US 37mm M51 APC Projectile "has a tracer cavity that is closed by a steel washer crimped to the base of the projectile". I have probably seen about a dozen M51s (I mostly see the B1 and B2 version) but have never seen the base with this arrangement. Was wondering if anyone has one and if they can post a picture of it's base/tracer cavity. Much appreciated!
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American 37mm M51 AP W/Tracer Cavity Closed by Steel Washer- Anyone have an example?
- Thread starter jeff w
- Start date
Thanks for the reply Steve. If you haven't seen it either (with your massive 37mm arsenal), that goes a long way towards confirming my suspicions and research. I am pretty certain M51 as described was not mass produced. More likely just a brief blip in its evolution.
TM9-1901 can be very misleading if taken at face value by a historian or collector.
TM9-1901 can be very misleading if taken at face value by a historian or collector.
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On the same subject - TM9-1901 goes on to say..."The tracer cavities of the M51B1 and M51B2 are closed by a metal disk".
Does anyone have an M51B1/B2 with a metal disk they can post a photo of? I don't think I've ever noticed one of those either.
Really curious about what the difference is between a "steel washer" (M51) and a "metal disk" (M51B1/B2).
I am willing to bet they decided to split the M51 into B1 and B2 because of the different piercing caps, not the washer/disk.
Here is a photo of an M51 with a B2 sloped cap (TM9-1901 says the M51 had the pointed B1 shaped cap!). Wrong again!
Does anyone have an M51B1/B2 with a metal disk they can post a photo of? I don't think I've ever noticed one of those either.
Really curious about what the difference is between a "steel washer" (M51) and a "metal disk" (M51B1/B2).
I am willing to bet they decided to split the M51 into B1 and B2 because of the different piercing caps, not the washer/disk.
Here is a photo of an M51 with a B2 sloped cap (TM9-1901 says the M51 had the pointed B1 shaped cap!). Wrong again!
I think you are expecting more from the TMs than they are able to support. In the early 80s as training and awareness I used to force my guys to submit changes (form in the back of every TM) to the TM 43-0001 series of ordnance pubs. When you get into the fine details all of these publications are full of small, sometimes significant errors. Finally after one series of change requests we got a call from the publication author, asking why we wanted the change and what difference it meant. After explaining that we used the publications as a simpler (non-classified) quick reference on ordnance ID and details, he explained that while he was the author of the document he was not an ordnance person, nor had he ever seen the ordnance he was writing about. Just a writer - He had no idea what he was writing about and how it related to any of the illustrations. I know that this was not far from the truth with the later EOD publications (TM 60 series), and doubt that it was any different for the WWII TM 9 series. A few years ago I was asked to do a review of some DHS contracted documents on some WMD stuff, same story. The author was a research desk jockey, had never seen a single piece that he was writing on and had no ordnance or WMD background. Always try to know your source material and never give it your full trust, good writers are not ordnance people and few ordnance people are good writers.
Great point!
And I'm sure that wartime stresses only made matters worse.