You can grind down/cut down the front "LPC Nub." I had to do it with mine. That is the only way I could get the M4 handguard to fit on flush.
You can't tell too good from that pic, but that's flush against the body.
There is an AK-47 "Clip" expansion chamber for the MR series. PBGrandpa has one on his MR2.
Trinity makes it as far as I know. Idk if they have one for the MR1 that will fit flush though.
EDIT: Grinding down the nub will not harm anything as long as you don't screw up the O-ring area. Thats the only part that makes a seal. Just grind it down enough so that the part fits flush.
I have no leakage problems with mine what so ever and I can get it out with ease. (Although I did burn my finger on the hot metal and I have a nice dead patch of skin on my pointer finger.
Keep a pan of COLD water next to you when cutting it down, as it gets REALLY hot.
I used a grinding wheel and a pair of those clamping pliers... forgot the name.