Longest Rail you can use on a 12.5 and get a can on it?

[M4Fundi]

Title says it all... what is the longest rail you can put on a 12.5" bbl and still easily get a Surefire SOCOM RC on it? Thanks!

[Shao]

You're looking at about an OAL of 17.7" on your barrel and can - so I don't know of any free floats that you would have trouble with. Go for a 15" and look cool. The SOCOM RC is 1.5" in diameter so take that into consideration - it won't fit under some of these new-fangled micro-tubes.

[Jwknutson17]

Title says it all... what is the longest rail you can put on a 12.5" bbl and still easily get a Surefire SOCOM RC on it? Thanks!

For a Socom RC you need about .7 inch barrel to actual handguard length difference. Here is a pic of a noveske 13.7 barrel with a Geissele SMR 13inch. I pretty sure this was what your looking for....


30348


Another reference.. The Geissele 10 inch SMR with a 11.5 barrel and SOCOM RC attached, you have .847 gap. That is with the suppressor on, but the locking collar lose extended it to its longest point. The measurement from rail to barrel would be no less then a .653 inch difference. With your 12.5 barrel and socom RC. The VERY longest rail you could run would be 11.847 inches. I give myself the .7 number difference as a little wiggle room..

[M4Fundi]

Thanks Jwknutson17.... that is the exact info I needed. I was hoping one of the 12" rails would work :-(

[M4Fundi]

Jwknutson17...Is that a photo of one of your rigs? Do you think the dimpling in any way effected the accuracy? Marvin do it?

I wish Bill would make an 11" rail!

[Jwknutson17]

Yes Mr Pitts did the dimple work. I never shot the barrel before dimpeling so I can't say for sure. See post here with the pics I posted up. I think it's about a 15-17 or so shot group with Black hills 77gr ammo on my last pic. Just whatever was in the box I had left. Range was at 89 yards as the benches were moved up to clean the shooting area. I just had Marvin dimple it to save a little weight. Has a mams with KAC CQB can now. Post 9 here.. https://www.m4carbine.net/showthread.php?160649-Will-it-fit-13-7-quot-barrel-and-suppressor

[Grip]

Yes Mr Pitts did the dimple work. I never shot the barrel before dimpeling so I can't say for sure. See post here with the pics I posted up. I think it's about a 18 or so shot group with Black hills 77gr ammo on my last pic. I just had Marvin dimple it to save a little weight. Has a mams with KAC can now. Post 9 here.. https://www.m4carbine.net/showthread.php?160649-Will-it-fit-13-7-quot-barrel-and-suppressor

Any idea how much weight the dimpling shed? I have my Noveske 13.7" barrel at Marvin's for dimpling before and behind the gas block. I forgot to weight the barrel with or without the gas block before i sent it.

[Jwknutson17]

I did not weigh it after I got it back. Guess I was too excited and assembled it immediately after opening the box. Marvin does some amazing work.

Another thing I've been on a kick for is having him cut down mid and car barrels to achive the minimal gap from rail to the suppressor. Instead of chasing handguards I normally wouldn't want or use, I've been cutting barrels to exact length. Just had him cut a 14.5 DD car barrel down to 13.1. Gas port stayed at .064. The 12 inch DD rails (RIS II and Slim 12, ones I have, are 12.43. The difference is .67 inches fits awesome with my suppressor set ups. Then had him cut a BCM mid BFH 16 inch barrel down to 13.7 without modifying the gas port at .74. Yet to shoot that barrel but expecting them to run just like the others. Soft and flat. Only use 5.56 ammo. Achieving the look and great performance I'm after while cutting down barrels with smaller gas ports, I couldn't be happier. Easier for me then trying to buy handguards to fit how I want on specific barrels. And might still need an adjustable gas block.

[M4Fundi]

Grip - there is a thread somewhere with how much weight you save with dimpling per inch and IIRC it is not much. If you do want to save a little wt and have really cool looking bbl then I would definitely have Marvin do it as I have only heard rave reviews and he has the professional pedigree to give you peace of mind.

Jwknutson17 - lucky you! hope to see more images of your builds and hear more about their performance!

[M4Fundi]

Distance?
Yes Mr Pitts did the dimple work. I never shot the barrel before dimpeling so I can't say for sure. See post here with the pics I posted up. I think it's about a 15-17 or so shot group with Black hills 77gr ammo on my last pic. Just whatever was in the box I had left. Range was at 89 yards as the benches were moved up to clean the shooting area. I just had Marvin dimple it to save a little weight. Has a mams with KAC CQB can now. Post 9 here.. https://www.m4carbine.net/showthread.php?160649-Will-it-fit-13-7-quot-barrel-and-suppressor

[Jwknutson17]

89 yards. Benches were moved up for there maintenance. normally set up at 100. Shooting off bench with bags. Geissele SSA-E trigger. No wind. Perfect conditions out. Couldn't have asked for a better day.