Are there any aftermarket conversions to make the AR-15 gas system a piston?  I'm totally sick of how dirty it gets and am looking for a solution.  Would changing the gas system be a detriment to accuracy?

There is nothing currently on the market to convert an AR to a piston type system.

Depending on the quality of the kit the effect on accuracy could be minimal or abysmal.

 There are a couple of alternatives out there right now...one is the VERY expensive ZM Weapons conversion.  It gets rid of the recoil spring and the direct gas....beautiful system...and probably worth every cent...but you'll have to see if anyone here has one.  I have never seen one, let alone shot one so I can't give you an opinion on that part.

 An intersting developement in this areas concerns one of our board members who has invented a piston driven upper that RETAINS the standard recoil sproing ( hee hee ) and buffer.  I have fired this weapon through a few stages of developement and fired a pre production model again just the other day.  I put three mags downrange and one of those was single handed, weak grip.  VERY positive. I believe the current developemental upper has over 3000 round through it with NO cleaning and NO malfunctions. AS to accuracy I could not tell you as the heads up sights' batteries died...hee hee...and since it was a developemental model it had no irons.

 Contact TOPCREST  (  just IM him ) for the details.

moon

 This is EXACTLY  why I will be buying an
AR-180B next year after the ban goes away .

A 10 years ago I read in a gun magazine, a man develop a mechanical conversion kit for the AR15/M16 that replaces the direct gas impingment arrangement currently used by a FAL-type piston-type where residue gases are used to cycle the bolt will will actually enter the bolt. Personally, I think the direct gas impingment system works quite well today after a rough start in the early years.