There is no mode selector for the m6a2, that's the a3. I can't say I have ever noticed the gas issue with any shooting speeds less than double/triple taps. So it does seem to happen under rapid fire. And yes, it would have to be a backpressure issue if there wasn't something amiss with the piston system, being that the carrier key is struck mechanically or not pneumatically. Next step I guess is to contact lwrc or head over to their forums.

