At the 2017 National Defense Industry Association small arms conference in April, the US Army revealed its efforts to produce new improved varieties of 40mm low velocity ammunition for the M203 and M320 grenade launchers. Product Director for Medium Caliber Ammunition Christopher Seacord’s presentation at NDIA lists three new types of 40mm ammunition: XM1166 High Explosive Air Burst (HEAB), XM1167 Door Breach (DB), and XM1168 Short Range Anti-Personnel (SRAP):
Not many details are given in the presentations about these three rounds, but some things are apparent. The XM1166 HEAB round appears to be very similar in desired capability to the 25mm airburst round developed for the now-cancelled XM25 Counter-Defilade Target Engagement (CDTE) weapon, called the “Punisher” colloquially. Wrapping the technology demonstrated by the XM25 program into the existing tried-and-true 40mm grenade launchers is in my opinion an excellent decision that could provide all of the desired capability with far lower risk.
The XM1167 Door Breaching round would provide an important capability for the infantry, as it would allow grenadiers to perform breaching functions without the need to carry shotguns for that purpose. It seems likely that the XM1167 would be the same grenade as (or one of similar design to) the Chemring 40mm breaching grenades tested late last year.
The result of a breaching test with a 40mm Chemring grenade. US Army photo, public domain
Rounding out the lineup, The 40mm XM1168 SRAP round appears to be a successor to the Vietnam-era 40mm M576 buckshot round.