Knight Modular Weapon System (MWS) versus A.R.M.S. Selective Integrated Rail (SIR)

Anthony · July 15, 2002, 07:01 PM

Hello Everyone,

Simple question...

Is Knight's Modular Weapon System (MWS) or A.R.M.S. Selective Integrated Rail (SIR) a better set up for the AR-15 carbine used for Close Quarters Battle (CQB)?

I have an AR-15 Carbine and am wondering which system is best for my needs.

Does anyone own either system or have experience with them?

If yes, what do you have mounted on yours?

What are the pros and cons of each system?

Can the two systems be installed by a non-gunsmith?

Thanks for the input.

- Anthony

woodland · July 15, 2002, 11:49 PM

This might be better suited for the Art of The Rifle forum. Probably get better response there.

Redlg155 · July 16, 2002, 01:20 AM

Yes..both can be installed by the user. The one exception is the military model SIR. The Civilian model can be installed by the user.

The primary advantage that the SIR has over the MWS is that the top rail mounts as a sleeve over the flatop rails, providing a stable mounting platform for optics.

But to be truthfull, both rate very high on the "neato" factor, but in the very end they are just extremely expensive handguards.

For a Carbine you can get a scout mounts for the A2 or Extended Arms#38 sleeve for the A3 and achieve the same results for much less. $100 bucks for the mounts. $300-$400 for the MWS or SIR.

Good Shooting
RED

Badger Arms · July 16, 2002, 03:42 AM

I'd get an extended SWAN Sleeve and save the money. In rapid fire, the handguards heat up very quickly to the point of being unuseable. It all depends on what you are going to mount. Talking to soldiers from Fort Lewis nearby, their M-4's with the pistol grips are fine but that and Night vision are the only two things they ever put on them. Even then, they don't like the fore-grip on when they have to hump the rifles as it just gets in the way.

Bartholomew Roberts · July 16, 2002, 10:18 AM

First, I'll assume that you have decided you need a rail system.

After that, I'd take this to AR-15.com and their Uppers, Lowers, Etc section. I've had a chance to get some hands on with both RAS and SIR now. I haven't had a chance to wring them out as much as I'd like; but I did get some information.

The SIR has the following things that RAS (current Army issue MWS) doesn't:

Free-floats barrel

Better cooling AND better protection from vented heat

Rails are removable so you only have rails where you want them (which is good as long as you don't lose the rails or attaching screws)

Top rail extends to receiver to give stable mounting platform for optics along full length of rail
(nice; but also raises height of rail causing sights like the EOtech and ACOG to be at a less optimum height than they were designed for. Not a major issue; but an irksome one for some people)

Optics mounted on top rail of handguard more stable than RAS

The SIR-C offers all of the above advantages and attaches with no more work than the RAS.

Downsides to the SIR are that it only works with a few types of back-up iron sights (ARMS #40 and Knight's 300m).

Tha main advantages RAS has over SIR are price and simplicity.

Comparing SIR to RAS really isn't a good comparison, a better comparison would be comparing SIR to Knight's new Free Floated RAS. The new FF-RAS has better cooling and heat protection since it isn't mounted to the barrel, it offers a more stable platform for optics, free-floats the barrel, and you can choose whether or not to add a top mounted rail.

Right now, I am actually looking at the Oly FIRSH, which seems to do most of what SIR and FF-RAS can do and costs $300 less.

Andrew Wyatt · July 16, 2002, 12:47 PM

I've handled and fired the SOPMOD m4's the marines use, and I'm not terribly fond of the RIS. The RIS makes the rifle heavier than it needs to be (especially if you only need one or two forend mounted things).

if you're going to mount a flashlight, why not buy a barrel or front sight mount? It weighs less and doesn't cost as much.

July 15, 2002, 07:01 PM	#1
Anthony Senior Member Join Date: December 29, 1998 Location: Dallas, Texas (United States) Posts: 416	Knight Modular Weapon System (MWS) versus A.R.M.S. Selective Integrated Rail (SIR) Hello Everyone, Simple question... Is Knight's Modular Weapon System (MWS) or A.R.M.S. Selective Integrated Rail (SIR) a better set up for the AR-15 carbine used for Close Quarters Battle (CQB)? I have an AR-15 Carbine and am wondering which system is best for my needs. Does anyone own either system or have experience with them? If yes, what do you have mounted on yours? What are the pros and cons of each system? Can the two systems be installed by a non-gunsmith? Thanks for the input. - Anthony

July 15, 2002, 11:49 PM	#2
woodland Senior Member Join Date: December 26, 2001 Location: western wa. Posts: 564	This might be better suited for the Art of The Rifle forum. Probably get better response there.

July 16, 2002, 01:20 AM	#3
Redlg155 Senior Member Join Date: March 13, 2001 Location: NW Florida Posts: 2,307	Yes..both can be installed by the user. The one exception is the military model SIR. The Civilian model can be installed by the user. The primary advantage that the SIR has over the MWS is that the top rail mounts as a sleeve over the flatop rails, providing a stable mounting platform for optics. But to be truthfull, both rate very high on the "neato" factor, but in the very end they are just extremely expensive handguards. For a Carbine you can get a scout mounts for the A2 or Extended Arms#38 sleeve for the A3 and achieve the same results for much less. $100 bucks for the mounts. $300-$400 for the MWS or SIR. Good Shooting RED

July 16, 2002, 03:42 AM	#4
Badger Arms Senior Member Join Date: July 2, 2000 Location: Harnett County, NC Posts: 1,700	I'd get an extended SWAN Sleeve and save the money. In rapid fire, the handguards heat up very quickly to the point of being unuseable. It all depends on what you are going to mount. Talking to soldiers from Fort Lewis nearby, their M-4's with the pistol grips are fine but that and Night vision are the only two things they ever put on them. Even then, they don't like the fore-grip on when they have to hump the rifles as it just gets in the way. __________________ We may or may not worship God, but John Moses Browning made sure we can choose.

July 16, 2002, 10:18 AM	#5
Bartholomew Roberts member Join Date: June 12, 2000 Location: Texas and Oklahoma area Posts: 8,462	First, I'll assume that you have decided you need a rail system. After that, I'd take this to AR-15.com and their Uppers, Lowers, Etc section. I've had a chance to get some hands on with both RAS and SIR now. I haven't had a chance to wring them out as much as I'd like; but I did get some information. The SIR has the following things that RAS (current Army issue MWS) doesn't: Free-floats barrel Better cooling AND better protection from vented heat Rails are removable so you only have rails where you want them (which is good as long as you don't lose the rails or attaching screws) Top rail extends to receiver to give stable mounting platform for optics along full length of rail (nice; but also raises height of rail causing sights like the EOtech and ACOG to be at a less optimum height than they were designed for. Not a major issue; but an irksome one for some people) Optics mounted on top rail of handguard more stable than RAS The SIR-C offers all of the above advantages and attaches with no more work than the RAS. Downsides to the SIR are that it only works with a few types of back-up iron sights (ARMS #40 and Knight's 300m). Tha main advantages RAS has over SIR are price and simplicity. Comparing SIR to RAS really isn't a good comparison, a better comparison would be comparing SIR to Knight's new Free Floated RAS. The new FF-RAS has better cooling and heat protection since it isn't mounted to the barrel, it offers a more stable platform for optics, free-floats the barrel, and you can choose whether or not to add a top mounted rail. Right now, I am actually looking at the Oly FIRSH, which seems to do most of what SIR and FF-RAS can do and costs $300 less.

July 16, 2002, 12:47 PM	#6
Andrew Wyatt Senior Member Join Date: June 5, 2002 Location: Bakersfield, Kommiefornia Posts: 549	I've handled and fired the SOPMOD m4's the marines use, and I'm not terribly fond of the RIS. The RIS makes the rifle heavier than it needs to be (especially if you only need one or two forend mounted things). if you're going to mount a flashlight, why not buy a barrel or front sight mount? It weighs less and doesn't cost as much.