Here are a couple 8 inch projectiles that are a mystery to me. I never paid much attention to them, causally glancing at them thinking they were 175mm HE projectiles that were missing their drive bands. Well, I've finally focused on trying to figure out what they are, and they are definitely not 175mm projectiles. They do measure 203mm on the OD, and they measure about 40.25 inches in OAL. There is no drive band groove that has been machined into the body, but it does have knurling/stippling toward the rear/base of the projectile. The base ID is threaded. They are both empty, and have large hollow cavity on their interior, so I'm sure they would have been intended to be loaded with some sort of HE filler. No markings that I can find, but due to the source, I am 95% confident they are of US origin. Could they be related to the MCLWG program, or possibly the HARP program? Any info would be much appreciated. Photos are attached.
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Unknown 8 inch Projectiles
- Thread starter condor
- Start date
Too heavy for HARP. HARP was to put satellites into space orbit. The smaller 5 inch projo is a 5 inch 54 cal Hi-Frag that was designed to have a plastic obturator as a rotating band. It has a very aggressive knurl for that obturator to grip onto.
From all the features of the 8 inch projectiles, I would say they are experimental long range cargo projectiles after the design of the 155mm M864, and the EFRB base burner designs of Gerald Bull. They are missing the stabilizing pads around the body to keep their axes concentric as they travel down the bore, which is why they were never fired. Since the top of the boattail is knurled and they are missing a gilding metal rotating band, and they were found with the 5 inch 54 of that design, I would say they were intended to have a plastic obturator, except the knurling isn't aggressive enough. The gilding metal rotating band could have been on the rocket motor like the 8 inch M650, except the 650 had external threads on the body and internal threads on the rocket motor section and was full diameter.
Cargo could be HE fill, chemical, submunition, illum, nuke, etc. I say cargo because they have a screw in steel base plug, instead of a monoblock body of steel. The threads of the boattail base could be used to add a baseburner or rocket motor to increase range.
If you wash them off, and take a wire brush to the body, you should be able to find an XM or T number for experimental or Test respectively if they are Army or a Mk (Mark) and Mod number if they are Navy. The ID would be stamped into the bodies along with a manufacturer code and lot number that would include the manufacturing date.
Since they wouldn't be fired, they are most likely proof of concept projectiles, or very early incomplete design.
The U.S. phased out the 8 inch, most likely due to Russian pressure to eliminate the possibility of being able to slip a nuke inside.
Do they have a groove(s) machined down the inside wall? if so it they would be to keep the cargo from rotating inside.
From all the features of the 8 inch projectiles, I would say they are experimental long range cargo projectiles after the design of the 155mm M864, and the EFRB base burner designs of Gerald Bull. They are missing the stabilizing pads around the body to keep their axes concentric as they travel down the bore, which is why they were never fired. Since the top of the boattail is knurled and they are missing a gilding metal rotating band, and they were found with the 5 inch 54 of that design, I would say they were intended to have a plastic obturator, except the knurling isn't aggressive enough. The gilding metal rotating band could have been on the rocket motor like the 8 inch M650, except the 650 had external threads on the body and internal threads on the rocket motor section and was full diameter.
Cargo could be HE fill, chemical, submunition, illum, nuke, etc. I say cargo because they have a screw in steel base plug, instead of a monoblock body of steel. The threads of the boattail base could be used to add a baseburner or rocket motor to increase range.
If you wash them off, and take a wire brush to the body, you should be able to find an XM or T number for experimental or Test respectively if they are Army or a Mk (Mark) and Mod number if they are Navy. The ID would be stamped into the bodies along with a manufacturer code and lot number that would include the manufacturing date.
Since they wouldn't be fired, they are most likely proof of concept projectiles, or very early incomplete design.
The U.S. phased out the 8 inch, most likely due to Russian pressure to eliminate the possibility of being able to slip a nuke inside.
Do they have a groove(s) machined down the inside wall? if so it they would be to keep the cargo from rotating inside.
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Thanks very much for the info. Why would the Russians want to focus on us phasing out the 8 inch, when we had similar nuclear capability with the 155mm XM454-W48 projectile? Did you receive my PM response to your PM? It doesn't show in my sent folder. If not, PM me your email address and I will contact you that way.
If anyone else recognizes these projectiles, please post any info that you can contribute. Thanks!
If anyone else recognizes these projectiles, please post any info that you can contribute. Thanks!
A couple of minor corrections here -
The 8-inch nuclear projectiles (M422/M753) were not cargo projectiles. The nuclear package was not something that could be transferred from one projectile to another, the projectiles were specifically designed, were unique and were not interchangeable, nor could they be utilized for anything else.
The M454 155mm projectile, while also nuclear, was a different class of weapon and was not comparable to the 8-inch. You are comparing a screwdriver to a pipewrench - both tools, but very different and for completely different purposes.
The 8-inch nuclear projectiles (M422/M753) were not cargo projectiles. The nuclear package was not something that could be transferred from one projectile to another, the projectiles were specifically designed, were unique and were not interchangeable, nor could they be utilized for anything else.
The M454 155mm projectile, while also nuclear, was a different class of weapon and was not comparable to the 8-inch. You are comparing a screwdriver to a pipewrench - both tools, but very different and for completely different purposes.