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11/27/2005 10:41:51 AM EDT
Okay, I'm very new to rails and all that that implies, but I'm signed up for a carbine class in January and I just found out I'll need a weapon mounted light.  I have a chance to get the KAC RIS in a trade and I'm wondering if any of you have any experience with these, will they fit my need, are they overkill, etc...  Any and all help will be appreciated.
11/27/2005 12:00:41 PM EDT
[#1]
Ah the good old RIS, that was what started my rail handguard frenzy that hasn't stopped
Go to quarterbore's excellent site to find out everything you need to know.
In addition to mounting a flash light, you can also mount a foregrip to work in conjunction with the light.
11/27/2005 12:12:49 PM EDT
[#2]
Nothing wrong with the RIS for mounting lights and stuff. It works alot like the surefire rail systems. It doesn't free float the bbl like the RAS but it works fine for me. I stand corrected.
For my money, I'd just go with the Surefire rail setup. I have both the RIS and the SF setups and I like the SF a little better. Customer service is certainly better and the SF rails don't make nearly as much noise! The heatshields in the RIS seem to be prone to rattle.
11/27/2005 12:38:27 PM EDT
[#3]
Okay, I'm an idiot.  What are these things made of, are they plastic, aluminum, etc...  And far from arguing with the Navy, they look like they would be a little loose.  
11/27/2005 12:52:21 PM EDT
[#4]
It's made of aluminum.  It's not recommended that you mount optics on it, but it's tight enough for mounting a light and foregrip.  The foregrip itself may wobble a bit on the rail, but even then the weapon is far from being unstable.
11/27/2005 5:58:56 PM EDT
[#5]

Quoted:
Okay, I'm an idiot.  What are these things made of, are they plastic, aluminum, etc...  And far from arguing with the Navy, they look like they would be a little loose.  


There's a clamping device builit into the upper section. On the RIS the clamp tightens to the handguard cap. The RAS (Which isn't a free float handguard) the clamping device is on the rear and engages the deltal ring.
11/27/2005 6:04:07 PM EDT
[#6]
The hook clamps onto the barrel nut, not slip/delta ring
11/27/2005 6:08:16 PM EDT
[#7]

Quoted:
The hook clamps onto the barrel nut, not slip/delta ring


On the RAS (Rail Adapter System). On the older RIS (Rail Interface System) the clamp is at the forward end.

I've owned both.
11/27/2005 6:26:02 PM EDT
[#8]

Quoted:

Quoted:
The hook clamps onto the barrel nut, not slip/delta ring


On the RAS (Rail Adapter System). On the older RIS (Rail Interface System) the clamp is at the forward end.

I've owned both.



But Duffy corrected your intial post.

RIS - Friction locks to the handguard cap

RAS - Fork Locks to the barrel nut.

11/27/2005 6:54:13 PM EDT
[#9]

Quoted:
But Duffy corrected your intial post.

RIS - Friction locks to the handguard cap

RAS - Fork Locks to the barrel nut.



Let me clarify. The upper and lower handguard sections of my RIS had flanges that fit into the handguard cap. Additionally there was a metal tab on the upper handguard section with one end sticking out the front of the handguard and the other held in place by a pivot pin. When installed, the handguard cap was between the handguard flange and the metal tab. Turning a set screw clamped the handguard cap between the handguard flange and the metal tab.
11/28/2005 3:57:49 AM EDT
[#10]
ANOTHER CONSIDERATION IN SELECTING BETWEEN THE KAC RIS AND THE KAC RAS IS THE FACT THAT THE RIS WILL WORK WITH ANY PROFILE BARREL. A BARREL SUITABLE FOR USE WITH THE RAS MUST MEASURE 0.835" - 0.855" IN DIAMETER JUST AFT OF THE FRONT SIGHT TOWER; M4 BARRELS FIT THIS DESCRIPTION.

THE KAC RAS WILL NOT BE AVAILABLE COMMERCIALLY UNTIL KNIGHT'S GETS CAUGHT UP WITH GOV'T CONTRACTS. THE KAC RIS IS HOWEVER AVAILABLE COMMERCIALLY AT THE PRESENT TIME.

WES GRANT
MSTN.BIZ
KNIGHT'S DEALER
11/28/2005 6:15:43 AM EDT
[#11]
Does the RIS actually wobble, or is it just less secure than the RAS?

I read somewhere that SEALs prefer the RIS to the RAS for the ability to use various barrel contours.  Is there any truth to this?  Are they just moving on to other rail systems?
11/28/2005 9:30:47 AM EDT
[#12]
THE RIS DOES NOT "RATTLE" IF THE FOREND CAP IS IN SPEC.

GIVE ENOUGH MUZZLE STRIKES USING A VERTICAL GRIP AND THE LOWER RAIL WITH EITHER THE RIS OR RAS, AND THS WILL BEND THE FOREND CAP, CAUSING THE BOTTOM RAIL TO BECOME LOOSE.

IF THIS IS A PROBLEM FOR YOU, MOUNT THE WHOLE THING UPSIDE DOWN. THE NAVY BOYZ THOUGHT OF THIS.

IF I HAD TO GUESS, THE SEALS USE THE KAC M4 RIS BECAUSE THAT'S WHAT THEY GET ISSUED. THEY ALL USE M4 CONTOUR BARRELS IN THEIR M4 AND CQB UPPERS.

I HAVE MY ORIGINAL, PROTOTYPE KAC M4 RIS, MACHINED FROM BILLET, THAT I GOT BACK IN '95. IT CURRENTLY LIVES ON MY 14.5" M4 SIMUNITIONS UPPER. IT HAS SEEN LOTS OF USE, BUT IS IN NO DANGER OF FALLING OFF.

WES GRANT
MSTN.BIZ
11/28/2005 3:06:02 PM EDT
[#13]

Quoted:
THE RIS DOES NOT "RATTLE" IF THE FOREND CAP IS IN SPEC.

GIVE ENOUGH MUZZLE STRIKES USING A VERTICAL GRIP AND THE LOWER RAIL WITH EITHER THE RIS OR RAS, AND THS WILL BEND THE FOREND CAP, CAUSING THE BOTTOM RAIL TO BECOME LOOSE.

IF THIS IS A PROBLEM FOR YOU, MOUNT THE WHOLE THING UPSIDE DOWN. THE NAVY BOYZ THOUGHT OF THIS.

WES GRANT
MSTN.BIZ



Can a RAS be installed upside down as well?
11/28/2005 5:00:23 PM EDT
[#14]
The RAS can be installed that way as well -- however you can get the UK RAS Lower if you want it locked on.

Many parts of NAVSOF and elsewhere have gone to RAS, MRE and other systems -- however some parts still buy the RIS - so you can see that while it may not be "cutting edge" it is still a decent piece of kit.
12/11/2005 10:34:00 AM EDT
[#15]

Quoted:
THE RIS DOES NOT "RATTLE" IF THE FOREND CAP IS IN SPEC.

GIVE ENOUGH MUZZLE STRIKES USING A VERTICAL GRIP AND THE LOWER RAIL WITH EITHER THE RIS OR RAS, AND THS WILL BEND THE FOREND CAP, CAUSING THE BOTTOM RAIL TO BECOME LOOSE.

IF THIS IS A PROBLEM FOR YOU, MOUNT THE WHOLE THING UPSIDE DOWN. THE NAVY BOYZ THOUGHT OF THIS.

IF I HAD TO GUESS, THE SEALS USE THE KAC M4 RIS BECAUSE THAT'S WHAT THEY GET ISSUED. THEY ALL USE M4 CONTOUR BARRELS IN THEIR M4 AND CQB UPPERS.

I HAVE MY ORIGINAL, PROTOTYPE KAC M4 RIS, MACHINED FROM BILLET, THAT I GOT BACK IN '95. IT CURRENTLY LIVES ON MY 14.5" M4 SIMUNITIONS UPPER. IT HAS SEEN LOTS OF USE, BUT IS IN NO DANGER OF FALLING OFF.

WES GRANT
MSTN.BIZ



Wes - Thank you very much for this little tip! It works like a champ
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