Help me build something better than a KAC SR15 14.5" upper

[cop1211]

Could some please clarify for me: What is required to install a URX4 on a legacy gas block? Does it fit or need it be "adjusted" to fit the over it?
Thanks

New gas block from KAC.

[KCBRUIN]

Upper will be going on a noveske lower.

from the OP

Noveske makes the AX556 lowers? And what upper exactly are you talking about? AX556?

The upper I'm talking about is the Noveske CQB.

[w3453l]

Thanks, sorry I got mixed up with a thread I read right before posting that; it was similar, but the OP said he was building off an AX lower.

[phaseshift]

Might not be better but I hear those Noveske guys, that make your lower, make a pretty decent upper.

or LMT MRP CQB.

The only reason why I'm keeping my noveske lower is because I already have it and don't want to spend the time to get another lower (however I might get in on the Battle Arms lower). Other than that I don't want to deal with Noveske ever again, had a bad experience with them.

[TehLlama]

How do you define "better"?

Exactly. Within a couple strict definitions, it's entirely possible to do so, and in a few cases for less money. For most applications - no. Not even close.

[phaseshift]

Exactly. Within a couple strict definitions, it's entirely possible to do so, and in a few cases for less money. For most applications - no. Not even close.

For most applications, multi purpose just straight BAD ASS upper that will take everything you give it and then some.

[wilson1911]

Could some please clarify for me: What is required to install a URX4 on a legacy gas block? Does it fit or need it be "adjusted" to fit the over it?
Thanks

I have a legacy with a urx 4 on it now, had a nsr. I just bought a bcm lopro block and used it. no need for the kac, since they are so pricey.

[hjmpanzr]

Okay so if I go with the regular sr15 16" and have Marvin cut it to 14.5 and dimple the barrel what am I losing and what am I gaining compared to the normal 14.5 with dimpled barrel?

Two points.

First. The 14.5" carbine upper is a medium contour dimpled barrel. It also has a different gas port size than a 16" SR-15. (See KAC industry thread early 2013 jack L made some references to it). However, apparently a lot of folks have chopped the 16" upper without opening the gas port and no apparent problems. I love the 14.5" carbine upper.

Second. As has been pointed out "better" barrel would need to be defined. But you are going to be hard pressed. You won't get KAC intermediate gas system or the E3 bolt but another option would be to get one of Marvin's "nefarious arms" barrels. They are stainless steel, midlength gas system and already dimpled.

[phaseshift]

I've got a factory, 14.5, as well as a legacy upper that I sent to Pitts for a cut down to 14.5, full dimple job, and had him install the URX4 rail.
The Pitts cut down and URX 4 is much lighter and I prefer that one to the factory 14.5.

I'd say get a Mod 1 or Mod 2, and send it to Pitts for a cut down and dimple job, and be done.
For the price of the factory. 14.5 upper you can get the whole rifle.

I think this will be the route I take I love KAC and I don't think I'll rest until I have a KAC upper and if I ever move out of Kali I'll get a lower as well.

[phaseshift]

Is there much of a difference between MOD 1 and MOD 2 SR15 Upper? If I get a MOD 2 upper and replace the URX 4 with URX 3.1 is there anything else that needs to be done to ensure proper fitting?