FORT BENNING, Ga. (May 15, 2013) -- Every athlete goes through slumps; it just so happens Sgt. 1st Class Jason Parker, a four-time Olympian with the U.S. Army Marksmanship Unit, is going through his at the right time.

Parker failed to reach the final round of his second consecutive International Shooting Sport Federation World Cup Friday at the Pool International Complex on Fort Benning. The World Cup was one of four that take place each year and the seventh time Fort Benning has hosted one.

Parker competed in the 50-meter three-position rifle and shot a qualification score of 1,159. It was a step up from the qualification score he shot in his last World Cup in Korea, 1,140, but still not on par for Parker, who won the gold medal at the Milan World Cup, earned a first-place finish in the Olympic Trials/USA Shooting National Championships and won three gold medals in 2011.

Parker said right now he is trying to adjust to a rule change that forces shooters to use the same rifle in each position -- standing, kneeling and prone. He had been using a different rifle for standing than he does for kneeling and prone.

"I'm working through a few issues," he said. "I'm trying to get that rifle to fit me the way it's supposed to. Once it's back in there, hopefully I'll be up there winning things again.

"The standing rifle I shot with was a wood stock and the one I'm using now has an aluminum stock. It just has different dimensions and settings, different weights. This one feels a little more heavy in the front than the other."

Fortunately for Parker, the struggles have conveniently come after the 2012 Olympics and qualifications for the 2016 Games in Rio de Janeiro don't begin until 2014.

"It's a year to try new things, build new positions and spend some specific time on things that need improvement," Parker said.

"When you go from shooting some of the best standings scores in the world to not doing very well, of course, it's frustrating. But like I said, just a couple of small position changes and the score should be back up to normal."

Among those in the field full of Olympians were a number of USAMU Soldiers out to test their skills for the first time in 2013 under the new set of rules implemented by the ISSF after the 2012 Olympics.

Service pistol shooter James Henderson competed in the men's 10-meter air-pistol match and finished in 22nd place after scoring a new career high in the event in just his second time competing in the Olympic-style discipline of air-pistol shooting. Henderson now turns his attention back to the service pistol when the USAMU hosts the 54th Interservice Pistol Championships in June here at Fort Benning. Brad Balsley competed in men's rapid fire pistol and finished on the outside looking in after placing 17th.

On the rifle range of Pool International Complex, 2012 Olympians Mike McPhail and Eric Uptagrafft both competed in the men's rifle prone match. McPhail made it to the final, finishing in seventh place overall. Uptagrafft came in 19th place.

USAMU Public Affairs Officer Michael Molinaro contributed to this report.