Skip to comments.USMC Adopts New Open-tip ‘SOST’ 5.56 Ammo
Posted on 06/30/2010 11:26:53 AM PDT by Joe Brower
USMC Adopts New Open-tip SOST 5.56 Ammo
After learning that M855 NATO ammo does not perform well from short-barreled rifles such as the M4 carbine, the U.S. Marine Corps has started issuing a new type of 5.56×45 ammo to its troops in Afghanistan. The new SOST (Special Operations Science and Technology) ammo, officially designated MK 318 MOD 0 Cartridge, Caliber 5.56mm Ball, Carbine, Barrier, features a different open-tip 62mm bullet. The new bullet, with a lead core (in the top half) and solid copper bottom half, is similar to hunting bullets such as Federals Trophy Bonded Bear Claw. The SOST bullet was designed by Federal/ATK, which will produce the loaded ammunition.
SOST 5.56 ammo
The new SOST ammo was first developed for use by SOCOM (Special Operations) in the SCAR rifle, which has a short, 13.8″ barrel. Even in short-barreled rifles, the SOST provides impressive ballistics achieving 2925 fps in a 14″ barrel. Compared to M855 ball ammo, SOST rounds are more lethal when shot from short-barreled rifles. According to the Marine Times, SOST ammunition delivers consistent, rapid fragmentation which shortens the time required to cause incapacitation of enemy combatants. Using an open-tip design common with some sniper ammunition, SOST rounds are designed to be barrier blind, meaning they stay on target better than existing M855 rounds after penetrating windshields, car doors and other objects. This is important to troops in the Middle Eastern theater who must engage insurgents inside vehicles or hiding behind barriers.
In Afghanistan, the USMC will issue SOST ammo for both the short-barreled M4 carbine as well as the original, full-length M16A4. The Corps purchased a couple million SOST rounds as part of a joint $6 million, 10.4-million-round buy in September enough to last the service several months in Afghanistan.
M855 Criticized by Ground Troops and Pentagon Testers
The standard Marine 5.56 round, the M855, was developed in the 1970s and approved as an official NATO round in 1980. In recent years, however, it has been the subject of widespread criticism from troops, who question whether it has enough punch to stop oncoming enemies.
In 2002, shortcomings in the M855′s performance were detailed in a report by Naval Surface Warfare Center Crane, Ind., according to Navy Department documents. Additional testing in 2005 showed shortcomings. The Pentagon issued a request to industry for improved ammunition the following year.
CLICK HERE for Full Report on New SOST MK 318 Ammunition.
BTW, posting this article was a royal, time-consuming PITA. First, I get it all typed in only to be told that the Marine Corps Times imparts copyright restrictions. Then I type this whole article in only to be told that it should go into "Bloggers". As a software engineer for over 25 years now, here's a suggestion to the FR webmasters: Warn people at the start of an op, not at the end.
“This thread is useless without pictures”
I want to see these bullets!
Ah. I should have refreshed before I hit reply
Yee Haw! Hollow points for use on the ragheads! About darn time1
Yee Haw! Hollow points for use on the ragheads! About darn time!
Many of my fellow soldiers are using hollow points for their M-4’s (5.56mm) that really improves the drop rate on enemy with first rounds!
eight deuce on the loose!
God Bless America!
I hope this means XM193 and M885 will become more available (and less expensive)....but I know better.
Millimeter, grain. Same thing, right?
I thought it had to be solid ball to be legal with respect to the Geneva Conventions, e.g. no dum dums, which this bullet appears to be an update thereof.
I would guess this is because the Taliban are not signatories of the Geneva Convention, and as un-uniformed troops are not entitled to any of its protections.
Sounds like they updated the round with faster burning powder as well.
see the bullets here:
While I was in the military, I asked why snipers use Match King hollow point bullets. It was explained to me that JAG ruled that military shooters cannot use a hollow point designed specifically to increase wounding but they can use a hollow point designed to increase accuracy. I was told that the hollow point manufacturing results in more uniform jacket thickness, better ballistic coefficient by moving bullet center to the rear and other factors that make them more accurate than FMJ rounds. This is why US military snipers have been allowed to use hollow point bullets for years. The better terminal ballistics are just a side benny of using the design which is supposed to be for accuracy. I do not know if this is true or not but it sounded good enough for me to believe it.
The free world are the only one stupid enough to obey the legalities with respect to the Geneva Conventions, the ragheads sure don’t.
I know that military and paramilitary forces of other nations (who are Geneva signatories) have used frangible munitions for their counterterrorist forces for a long time. I assumed that this was because non-uniformed combatants were not afforded Geneva protections, but the info you present may be the justification. IIRC, the Blitz Action Trauma (BAT) was designed for GSG9...it had a plastic tip that allowed smooth feeding in weapons designed for FMJ ammo, but the tip merely covered a gaping hollow-point...
pen-tip bullets have been approved for use by U.S. forces for decades, but are sometimes confused with hollow-point rounds, which expand in human tissue after impact, causing unnecessary suffering, according to widely accepted international treaties signed following the Hague peace conventions held in the Netherlands in 1899 and 1907.
Unnecessary suffering? Are you fricking kidding me?!?!?!ANYone hit by a 5.56 bullet traveling at high speeds is gonna have "suffering".
Unnecessary?!?! Stay outta the way of the bullet!
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