A version of this article first appeared a few weeks ago in Issue 38 of our weekly Soldier Systems Digest newsletter. It was prompted by a vendor demonstrating their candidate carbine leading many to believe the program had already selected a carbine. That is not true. The article has been slightly modified from the original to clarify some points. This is a link to the article we posted after the program was announced in June. It details the requirements. We’ve learned a lot since then.
What HICAR is…
A USSOCOM effort to field a new Stoner-pattern carbine capable of firing the high pressure, 5.56mm cartridge known as M855A1+.
The cartridge has been under development with Federal on behalf of Picatonny Arsenal for several years and referred to as “5.56 Max.”
The cartridge uses Federal’s Peak alloy case technology to deliver chamber pressures in excess of 80,000 psi. This was originally developed for the 7mm Backcountry cartridge.
What HICAR is NOT…
It is not an Army program.
It is not going to replace the 900,000+ M4 carbines currently in Army service.
The Army currently has no plans to adopt M855A1+ ammunition. However, they have paid for its development and are monitoring the program closely.
NGSW remains the Army’s primary small arms modernization effort. In fact, the Army is moving forward with fielding of the XM8 carbine to replace the M7.
The Program as it stands…
There are currently three competitors in down select who will deliver rifles to the command very soon to undergo live fire evaluation. All three companies were directed to NOT publicly acknowledge their participation, so if a company is showing you what they’ve got, they aren’t part of the program.
USSOCOM has POMed (budgeted) for both rifles and ammunition and is dedicated to this program. They currently have courses of action which procure full weapons as well as an Upper Receiver Group-only option. This is why the candidate systems must be M4 compatible.
Numbers are not being publicly disclosed but I would put them as similar to USMC M27 numbers, eventually.
FY27 will see the command down select to one candidate weapon and transition to an OTA for rapid procurement in FY28.
The ammunition…
I have concerns over referring to the ammo as M855A1+. While the HICAR must be capable of shooting standard pressure rounds as well as the new ammo, the inverse isn’t true for legacy M4s. It’s quite possible that high pressure rounds will end up in standard M4s. This is particularly the case for enablers who will likely not be armed with HICAR but embedded within SOF formations operationally. Will this result in catastrophic failures? No, but those high pressure rounds will certainly curtail the life of the M4. However, the danger does exist that an M4 firing M855A1+ may face broken bolt lugs or other failures during a fire fight.
It is my understanding that the ammunition has been safety certified, including passing an obstructed barrel test on an M4A1.
I assert the ammo absolutely needs a new nomenclature and DODIC. I’m also not a fan of the “hyper” velocity moniker. We may one day actually create true hyper velocity ammunition which is in excess of 5,000 fps. This ammunition, while impressive, doesn’t even approach that velocity.
An additional point is that the current developmental ammo (M855A1A+) is tightly controlled and not available outside of this program. I fully expect the ammunition to change over time, as they continue to dial-in its performance. That means, anyone outside of the program is producing their own ammunition. There is currently NO commercially available high pressure ammunition.
While I fully believe that high-pressure ammunition is the future, it faces a serious commercial challenge.
The Sporting Arms Ammunition Manufacturers’ Institute sets industry standards for ammunition. When a new ammunition is proposed, SAAMI certifies both the cartridge and chamber. This is because the chamber must be capable of safely firing the ammunition it is associated with.
Most companies in industry will be reticent to offer new ammunition which has not been built to a chamber spec. In this case, .223 for commercial sales. For years we’ve heard about the “dangers” of firing military-grade 5.56mm NATO ammunition in .223 chambers. Consequently, many commercial carbines use barrels chambers for 223 Wylde instead. However, those concerns are laughable compared to the pressures we are seeing with high pressure ammo.
Considering what happens to 300 BLK ammunition fired in .223 carbines, fear mongering will assuredly ensue in firearms social media once commercial high pressure ammunition is introduced.
We are likely stuck in a chicken-or-the-egg cycle, at least in the near-term as ammunition companies weigh whether or not it is worth loading ammunition for firearms that don’t yet exist in great numbers. This is the same thing that happens every time a new caliber is introduced.
The future is high pressure but I believe the military will lead the way in its adoption.
Eric Graves
Founder, SSD
Photo by K. Kassens
United States Army John F. Kennedy Special Warfare Center and School
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I completely agree on the nomenclature change. It’s not like the government ran out of numbers, so why the need to cling to M855 in the naming convention? The change to the -A1 round was significant enough to warrant a new designation, and again for this round.
I’m assuming the “A1+” designation is an informal placeholder until a formal one is agreed upon.
The original HICAR post explicitly raised the possibility of HICAR being a part of an “M4A2”.
If I understand you correctly SSD, your point here is that the original post was privately outlining a possible future for HICAR with Big Army, and this post is meant to clarify that Big Army has made no official pronouncements regarding HICAR, correct?
As an aside, if Geissele is out, that leaves several other companies that have been silent: KAC, LMT, DD, Sig, and SOLGW come to the front of my mind.
With SureFire holding their 5.56 ICAR so thought I would imagine that that one is a possible as well.
“Moving forward with fielding of the XM8” is underselling it a bit.
The Army was fielding M7s but they had so many issues, that the entire fielding was halted. Sig built the XM8 to address some of the issues and they are moving forward, but both it and the M250 have unaddressed issues that are leaving many skeptical. The reputation for the weapon is horrible and units are pushing back quite a bit.
Whether or not any of it will matter in the short term is hard to say, but the existence of the XM8 is not a positive thing for the program.
Do you have an actual experience with the weapon or the interaction with the program office? Or, are you just running with what you have read online?
Pure opinion but, M4A1 in the Army should get an ergonomic update. Not so sold it needs the whole HICAR though. I mean M4A1 for the Army was locked 20 years ago. With the Adoption of the M7 now M8 the Army adopted a bunch of Mloc accessories and furniture that would fit most of the Commercial AR15 M4 patterned rifle at a decent gun shop made the the same manufacturer. So if they are going M8 for the infantry might as synergize (yes I used a buzz word.) an Mlok rail, the same stock shoe and pistol grip.
Curious what led them to choose the PEAK alloy over stainless steel?
Steel isn’t as ductile as Brass and doesn’t work well as a cartridge case without lacquer to prevent it adhering to a hot barrel. Their alloy works more like brass.
High pressure cartridges are why ARMAD steel was selected…it withstands more heating and cooling cycles before losing hardness, so it resists erosion somewhat longer and there is good science on that. You can also make an adapted upper for the M-4 that incorporates smaller ports, perhaps an adjustable gas block…maybe improved bolt material and designs like the conical Sharps Brothers from a few years ago. More beef around the left side of the receiver where the “lump” is would prevent specific problems with blowing out the sidewall…and do the POF roller pivot pin!
That more power is “good” is a given…now make improved projectiles and guns to match the improved cartridge.