KAC SR-15 E3 Mod 2 URX 4 removal

**capt46wfd** · 03-18-17, 01:59

As crazy as it my sound, I want to put a Hodge Defense Wedge Lock Rail on my SR-15 E3 Mod 2.

I've scoured the internet looking for the wrenches for the Mod 2 gas block retaining nut and the URX 4. Any help on where to source these wrenches would be greatly appreciated.

Thanks in advance

**ABNAK** · 03-18-17, 07:00

Good luck. I don't think Knight's sells them. As with anything from Knight's, the rail and wrench are proprietary. It would seem that they prefer one of their certified armorers (who there are only two of in the country IIRC) to work on their stuff. Guess it keeps folks from Bubba'ing things up and then blaming the product.

I thought I saw somewhere a few months back where someone made a wrench.

**scottryan** · 03-18-17, 08:02

Originally Posted by capt46wfd

As crazy as it my sound, I want to put a Hodge Defense Wedge Lock Rail on my SR-15 E3 Mod 2.

I've scoured the internet looking for the wrenches for the Mod 2 gas block retaining nut and the URX 4. Any help on where to source these wrenches would be greatly appreciated.

Thanks in advance

You are making a mistake.

**MSparks909** · 03-18-17, 08:31

Originally Posted by capt46wfd

As crazy as it my sound, I want to put a Hodge Defense Wedge Lock Rail on my SR-15 E3 Mod 2.

I've scoured the internet looking for the wrenches for the Mod 2 gas block retaining nut and the URX 4. Any help on where to source these wrenches would be greatly appreciated.

Thanks in advance

Just curious...but what's the reasoning behind the swap? Coming from someone who owns a Mod 2, I think you would be making a mistake by swapping the rail but to each his own.

**Jwknutson17** · 03-18-17, 08:45

I have swapped a few. But the hodge won't fit. See the response I sent to another member below:

Ok, so I mic'ed up some measurements. The URX3.1 rail is about as close to making it fit as you can possibly get. I can flex the barrel in both upwards and downwards and make contact with the rail. same with side to side with the gas tube nut. IMO It has enough clearance to not ever be an issue, but any closer and I would be machining the inside of the rail for my piece of mind. The URX4 is actually .2 inches taller from inside of the handguard to the top notch cutout where the gas tube is, right under the 12 pic section.

The Wedgelock, if you look in the inside, had those drop down little humps under the pic rail (on the inside). So the usable space / opening is 1.51 ish on the wedgelock. You need 1.61 inches for it to even be possible. From the center of the muzzle/barrel, you MUST have one inch (1.000) of space to the top or Center of muzzle to the highest point inside the hand guard for the top of the gas block. From the center of the muzzle/barrel, underneath you need the remainder .6xx ish.

I know the .1 difference doesn't sound like a lot, but you will hit inside of the rail for 100% sure on the inside top.

**Jwknutson17** · 03-18-17, 08:48

Also,

See post # 2672 and 2678 of this thread here... https://www.m4carbine.net/showthread...-ve-got/page90

**Jwknutson17** · 03-18-17, 08:57

I was previously a tech in the auto industry and have access to many different spanner type sockets. Keep in mind, you still have to modify one, or make one as I did. The gas block on a few was a bigger pain to get off then nut. You need to use a special puller tool for that also.

Long story short. Not worth it. If I didn't already have 5 urx4 Mlok railed uppers I sure as heck would not have gone down the road again to put a 3.1 rail on a mod2. Would have just grabbed a mod1 from the safe or another rifle with the wedgelock.

I asked back in December here... and all I got was crickets.. https://www.m4carbine.net/showthread...-block-removal