Military retirees are outraged that Congress will start voting Thursday on a budget deal that trims military pensions, calling the move "an egregious breach of faith."

"The Democratic Senate Armed Services Chairman says they are going look at this in the new year when Congress returns. But they are up against, certainly, some lawmakers who think that this is terrible," CNN's Dana Bash reports.

The Military Coalition, some 27 military groups, wrote to leaders in Congress and President Obama late Wednesday about their "strong objection" and "grave concern" over the budget deal.

The deal cuts pension cost of living raises by 1 percentage point for military retirees who aren't disabled and not yet 62 years old. Cost of living hikes are automatic raises intended to keep up with inflation.

The problem is, most military retirees are a lot younger than private sector retirees. They enlist in their 20's and retire in their 40's. Very few stay on till they are 62 - those who may be lucky enough to escape major injuries at war, or rose to higher echelons in the military system.

When compounded, the 1 percentage point cut could result in much more than a 20% reduction in retiree pensions over 20 years.

Senator Patty Murray responded on “New Day” Wednesday saying this provision was just one of many compromises. (SEE VIDEO BELOW)

"There's things in this I like. There are things in this I don't like," Senator Murray said.

"But at the end of the day, if we couldn't find a compromise on how we move forward, then we would be facing a $20 billion hit to our defense industry—meaning layoffs, and uncertainty, and a lot of furloughs harming a lot of families across the country.”