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View Full Version : Does the M4/SPR fit the LMT 12" piston?


NetJunkie
05-19-09, 09:21
I know this has been discussed but I can't find it in search. Will the M4/SPR fit or does it hit the piston end?
AlanD
05-29-09, 22:02
I emailed LMT perhaps 6 months ago and they replied that an M4/SPR would not fit.
Walker Precision
05-30-09, 21:48
The SPR/M4 requires about 2.5" of unobstructed barrel behind the muzzle to properly fit. The 12" LMT piston barrels are just over 1.25" to the gas block. An M4-2000 or an M4-1000 will fit, but will prevent the piston from being removed without removing the flash hider or pulling the barrel.

http://i46.photobucket.com/albums/f108/walkerprecision/LMTPistonSBR002.jpg

http://i46.photobucket.com/albums/f108/walkerprecision/LMTPistonSBR007.jpg

http://i46.photobucket.com/albums/f108/walkerprecision/LMTPistonSBR004.jpg
AlanD
06-01-09, 18:46
Chris,

Thank you for the info and photos.

Alan
Walker Precision
06-01-09, 21:29
No problem. Hope the info is helpful.
openbolt
06-08-09, 14:38
An M4-2000 or an M4-1000 will fit, but will prevent the piston from being removed without removing the flash hider or pulling the barrel.



This information is incorrect. I own a 12" LMT CQB piston rifle in 5.56mm and the M4-1000 AAC can. I think I was the first person to figure out that you can seperate the piston and push rod from each other while it is inside the upper. What I do:

1) Remove the can.
2) Pull the upper from the lower.
3)On a bench flip the upper upside down so the op-rod is visible, grab the op-rod with a smooth jawed pair if needle nose pliers, gently pull the op-rod from the piston. The two parts will now be loose/seperated. Keep rearward pressure on the op-rod while manipulating the gas plug out from the front of the piston housing.
4) Then just let the op-rod run forward under it's own spring pressure. Done deal.

This process is even easier if you want to go to the trouble of pulling the Q/C barrel.

When I discovered this I reported this procedure to AAC's Mike Meyer as well as Gene Swanson over at LMT. Both were grateful for the tip.

Hope this helps,

openbolt
Walker Precision
06-08-09, 20:46
Thanks for the info.