Back in May, when NSWC Crane posted the Hypervelocity Improved Capability Assault Rifle (HICAR) solicitation, I closed my article by asking whether any currently available carbine platform was genuinely built to handle sustained fire at 82,000 PSI, or whether every vendor would need a clean-sheet bolt and barrel design to compete? Geissele Automatics has answered, and the answer sits on a product page with a SKU on it. Let’s take a look at their first iteration. BackgroundThe high-pressure 6.8mm hybrid cartridge used by the Next Generation Squad Weapon (NGSW) is trying to replace the 5.56mm. But the 5.56 carbines are far from dead and are doing their best to keep themselves more than relevant in the modern arsenal, together with developments in ammunition, of course. Despite the NGSW program's momentum, the 5.56mm platform's massive installed base, decades of ammunition supply chains, lower cost, and proven reliability mean it's not going anywhere quickly. Military transitions often take decades, or die along the route as they become redundant, and the commercial market moves even slower. The Geissele HICAR and its componentsThe Geissele HICAR is an 11.5-inch 5.56 carbine that the company describes as optimized to harness the full potential of high-pressure 5.56 ammunition. The high-pressure ammunition delivers velocity gains at the cost of additional component stress and accelerated barrel wear, but the HICAR has answers to both problems. I can only imagine the cost of test firing and proofing this system, let alone the time it takes to do it properly. The components doing the heavy lifting are exactly the ones the solicitation punished first. Geissele calls the bolt the BB-62 Reinforced Bolt, describing it as proprietary and built to handle the extreme pressures of evolving ammunition technology. It is paired with what the company lists as an Enhanced BCG for High Pressure Ammunition Applications. The 11.5-inch cold hammer forged barrel is made from GNB200 barrel steel, which Geissele developed in cooperation with Carpenter Technology and the U.S. Army, specially formulated for high-temperature wear resistance. That barrel steel work predates the HICAR solicitation, having run through a cooperative research agreement that TFB has covered previously. The rifling is called GZX gain twist. Exactly what’s hidden behind the abbreviation and technology is not disclosed just yet, but expect a progressively changing twist profile. For instance, both Proof and Seekins Precision have similar barrels on the market, and TFB covered Proof’s PXT Barrel Technology in this article.I think it’s safe to say that this is a rifle barrel with special rifling that twists faster toward the front than the back. The grooves probably have smooth, rounded edges where they meet the ridges, instead of sharp corners. The exponential gain twist starts nearly straight and gradually accelerates, applying most of its rotation near the muzzle, giving a gentler curve than the traditional gain twist.I would also presume that’s how they get higher velocity, as there would be less obstruction for the bullet in the beginning before forcing it to spin more and more gradually.The gas system runs Geissele's Phased Array with the Tri-Port system, with gas length listed simply as custom. It doesn’t appear to be adjustable. The buffer assembly is also listed as custom.The receiver set is the GFR (Geissele Fighting Rifle) ambidextrous billet lower and GFR billet upper with a riveted cam race and fenced bolt catch. Furniture includes a 10.5-inch MK24 rail, an Airborne Charging Handle, an SSF-X trigger, a Magpul CTR stock, and a Geissele A17 grip.One line in the specification sheet stands out on its own: the Safety Selector is listed with an optional High Speed Selector for anti-drone capabilities. That’s a fancy word for a 45-degree throw selector. Geissele HICAR performanceOn the performance side, Geissele's own product page publishes no velocity or pressure figures. But from Geissele's mid-August (2026) reveal videos, we know the demonstration load drives a 77-grain Sierra MatchKing to roughly 2,700 ft/s from the 11.5-inch barrel, against approximately 2,300 to 2,350 ft/s for the same bullet from the same barrel at conventional pressure. Per that report, Geissele loads the ammunition in-house to a minimum of 82,000 PSI on Federal Peak Alloy steel cases, and Bill Geissele himself puts the specific load shown at over 85,000 PSI (Source). The same video states Geissele's lead engineers shot the rifle in a match on the day of the reveal and connected past 800 yards, with at least 1 MOA claimed. Personally, I’m interested in how much more recoil the system generates. As a competitor (not a warrior), I’m a rifle gas length type of person, for the smoothest felt recoil. My shorter systems (yes, I have those too) run very hot and are a lot ”bumpier” for follow-up shots, but aren’t even close to these kinds of bullet weights or pressure. In one of the videos, Geissele shoots the system in full-auto and the recoil seems manageable, but we only get to see the back of the shooter and a rainbow of spent brass, not really the rifle itself or how the barrel moves. Anyway, almost everything in Geissele’s spec maps directly onto the numbers from the solicitation - probably not a coincidence. Crane's requirement calls for an 11- to 12-inch barrel, function with M855A1+ at 82,000 PSI, 1 MOA average mean radius at threshold, and a barrel life floor of 8,000 rounds measured against M855A1+. Geissele's listed rifle hits the barrel length window and the claimed accuracy figure. The company publishes nothing on barrel life, mean rounds between stoppages, submersion, or temperature range.Ammunition Data from the Geissele video. Note that HICAR vendors will not get to submit their own ammunition. The live-fire pitch days run September 15 and 16 at Fort Moore's Parks Range on government-furnished M855A1+, not on vendor loads (Source). Manually reloaded ammunition usually meets higher standards than stuff being made in a mass-production line. USSOCOM has not yet published the invited vendor list from the June 29 down-select, and we are about as curious as you are. CompetitorsPotential competitors to the Geissele Hicar could be alternative versions of the SOLGW MK1 or the Surefire ICAR, but potentially a few more. Geissele HICAR Specifications (first iteration):Caliber: 5.56mmBarrel: 11.5", GZX gain twist, cold hammer forged GNB200 artillery barrel steelBolt: BB-62 reinforced bolt for high pressure ammunition applicationsBolt carrier group: Enhanced BCG for high pressure ammunition applicationsUpper receiver: GFR billet, riveted cam race, fenced bolt catchLower receiver: GFR ambidextrous billetRail: 10.5" MK24, zero laser shiftGas block: Antistrike super compactGas port: Geissele Phased Array with Tri-Port systemGas length: CustomBuffer assembly: CustomBuffer tube: Mil-Spec 6-positionMuzzle device: HUXWRX Flash Hider QD 556, 5/8x24Trigger: SSF-XSafety: Super Configurable Safety Selector, optional High Speed Selector for anti-drone capabilitiesCharging handle: Airborne Charging Handle (ACH)Lower parts kit: Ultra DutyStock: Magpul CTRGrip: Geissele A17Length collapsed: 28 1/4"Length extended: 31 1/2"Weight: Approx. 6.6 lbsColor: DDC (Desert Dirt Color)SKU: 08-891 Comparing the Geissele HICAR against the HICAR thresholds from the solicitationBarrel length: 11 to 12 inches required, 11.5 inches listedWeight unloaded without suppressor: 8 lbs threshold, 6.5 lbs objective, approx. 6.6 lbs listedOverall length: 31 inches threshold, 28 inches objective, 28 1/4" collapsed and 31 1/2" extended listedAccuracy: 1 MOA average mean radius threshold, at least 1 MOA claimed in the reveal videos.Chamber pressure rating: 82,000 PSI (M855A1+) threshold, in-house demonstration ammunition loaded to a minimum of 82,000 PSI per demonstration video. For more details, check out the Geissele Hyper-velocity Improved Capability Assault Rifle (HICAR) product page: https://geissele.com/geissele-hicar.html For more details about the Hypervelocity Improved Capability Assault Rifle, check the latest amendment to the solicitation on SAM.gov.All images are from Geissele Automatics.