U.S. Army soldiers at war in Afghanistan have made personal modifications to the M4 carbine to improve its effectiveness, according to a news report.

Army Senior Warrant Officer Russton Kramer, a longtime Green Beret, said he and fellow Special Forces soldiers buy off-the-shelf triggers and other components and overhaul the M4A1 commando version of the assault rifle, according to an article by Rowan Scarborough, a reporter for The Washington Times.

"The reliability is not there," the Silver Star recipient told the reporter. "I would prefer to use something else. If I could grab something else, I would."

The two-part series is the latest to investigate the reliability of the Army's standard-issue carbine made by Colt Defense LLC. The weapon has been upgraded by the service in recent years, but remains in essence a shorter, lighter version of the Vietnam-era M16.

Military.com's Matt Cox, a frequent contributor to Kit Up, last year broke the news that the Army nixed plans to hold a competition to replace the rifle despite interest from such gun-makers as Heckler & Koch, FNH-USA, Remington Defense and Adcor Defense Inc., in addition to Colt.

The decision stemmed in part from a "careful consideration of the Army’s operational requirements in the context of the available small arms technology, the constrained fiscal environment, and the capability of our current carbines," Cox reported at the time.

The issues Kramer touched on are familiar to other soldiers.

Clinton Romesha, a former Army staff sergeant who received the Medal of Honor for his heroic actions during the battle at Combat Outpost Keating in 2009 in Afghanistan, said he was disappointed when he heard the Army ended the competition to find a potential successor to the M4 gas-operated system.

"When you start hearing all the chatter, 'Hey, we're looking to get a new product, we're looking to upgrade something that's been around since the Vietnam War,' you get a little excited," he said in an interview with Military.com at last month's SHOT Show in Las Vegas. "But when everything just dried up and went away, it was kind of a disheartening feeling as a soldier to see that -- to see good products out there that weren't available to you."

Now out of the military and working as a representative for Adcor, among other firms, Romesha praised the company's A-556 Elite rifle for its piston-operated system, free-floating barrel, forward ambidextrous charging handle, and polymer dust cover that seals the system from dirt and debris, among other features.

"There's nothing more important for a soldier than to know when he's carrying his weapon system, it's going to work," he said. "What they developed here is a platform that every time you squeeze the trigger, it's going to go bang instead of click."

But Romesha, who also served two tours in Iraq, said the Army has a history of acquisition missteps -- not just with guns and bigger pieces of equipment, but also with items as small as boots.

When he and his fellow soldiers initially arrived in Afghanistan, they were left with "putting the old tan leathers on and breaking them in for three weeks just to get them comfortable enough to go hiking up and down the mountains." Luckily, he said, their brigade commander, "went out of his way" to get them Merrell hiking shoes.