Info on XM864 155mm submunition shell

[steve rb]

Recently acquired one of these, larger than the L15 ICM, fired but still clearly stencilled, couldn't find any info in my Jane's book or on the web, what was the XM864...any ideas?

cheers
steve

 

[steve rb]

Or... Is the X purely some sort of experimental designation prior to it becoming the M864...? Seems to fit...

 

[US-Subs]

M42 submunitions, basically an M463 with a base bleed.

 

[orpheus72]

Hi STeve,

The X denotes the development stage of an item (so yes, experimental)

extract from "MIL-STD-1168B - US Ammo Lot Numbering (1998) " :

4.1.4.4.1.3 Development.
When a development category (XM) model number is standardized, the next lot produced as the standardized model will simply be assigned the next higher sequential interfix number. The last sequence number will again revert to “001”.Example: Fuze, XM302 with lot number AMC97H002-004 converts to fuze, M302Al.

 

[HAZORD]

As Jeff has said, the projectile is similar to an M483 with a basebleed unit as the base plug. There is a difference between the profile of the 2 rounds on the Ogive and the 483 just has an aluminum base plug.

Attached photo of a basebleed unit or baseburner as they are also called. It is designed to extend the range of the projectile by bleeding off enough gas to eliminate the drag at the rear of the projectile.

 

[steve rb]

Thanks folks, exactly it, was reading up on the M864 last night - it's still got its blue band so a practice development shell it is. Was retrofitted with a new dummy fuze, non bleed base and submunitions tray post firing.

 

[Gunnerwho?]

L15 is not ICM, it is a standard 155mm HE round conforming to the early 1960s agreement that was primarliy concerned with the 39 calibre barrel.