KAC SR-25 6.5 Creedmoor question
- Thread starter TacticalPlinker
- Start date
Those slots are supposed to start a little after where those 6" mlok panels end and then they go all the way to the end. So it looks like you're missing a few, judging by the ones I have. The keymod versions are the same as the mlok versions that I have.
Has nothing to do with the gas, that uses a castle nut to hold on an indexed gas block that slips on.
It won't hurt anything, and maybe they did that intentionally but I can't see why. Looks more like something that slipped by QC to me and if all of 'em were cut that way and not just that one I can see how it'd be easy to miss I guess.
I'd give KAC a call, but for sure it won't hurt anything. If it weren't for that ONE cut, had they not done it at all, I bet you'd never have noticed? I had to go look at mine after you brought it up.
Has nothing to do with the gas, that uses a castle nut to hold on an indexed gas block that slips on.
It won't hurt anything, and maybe they did that intentionally but I can't see why. Looks more like something that slipped by QC to me and if all of 'em were cut that way and not just that one I can see how it'd be easy to miss I guess.
I'd give KAC a call, but for sure it won't hurt anything. If it weren't for that ONE cut, had they not done it at all, I bet you'd never have noticed? I had to go look at mine after you brought it up.
It is specific to the URX6 and was done intentionally. You see it on both the short and long versions. For the life of me I can’t find where KAC discussed it, but something like “gas expansion” comes to mind for some reason. Maybe wiggle room for the gas block during firing? I’m trying to track it down.
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Okay just to clarify I forgot to include that this is not mine, it's a picture of one at a vendor.. That being said I'm still waiting for mine to come in.
Okay, I stand corrected.
But as to why I can't figure it out.
What's the difference in the 4 vs. the 6 and where did 5 go!?
None of this shit is on KAC's site so I guess they're not selling 'em yet. Looks like they come on new rifles though.
Seriously, do I have to answer every question on these forums?
It’s a blow-hole. You blow on the gas block for rapid cooling after each mag-dump.
It’s a blow-hole. You blow on the gas block for rapid cooling after each mag-dump.
KAC rail naming nomenclature is all over the place. The 5 was probably what’s actually going to be the 4.1, who knows. Among the differences between URX4 and URX6 is that the latter is not a one piece/IBN (integrated barrel nut) unit. It is keyed to the receiver like a Geissele or HK rail and actually uses a non-indexing barrel nut to retain the barrel/attach the handguard.
The leading edge of pic rail on the receiver has a machined slot to receive the matching tab from the URX6.
@Strykervet that has nothing to do with an accidental QC error.
Its a manufacturing fixture access hole. They were implemented into the design after the introduction of the E2 Gas System.
And yes the URX 6 is proprietary to the upper receiver as it has a integrated indexing/anti flex notch.
An no URX 5 was not a commercial offering (as of this time).
Its a manufacturing fixture access hole. They were implemented into the design after the introduction of the E2 Gas System.
And yes the URX 6 is proprietary to the upper receiver as it has a integrated indexing/anti flex notch.
An no URX 5 was not a commercial offering (as of this time).
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Well, if I had my guess I'd say they will be... KAC used to only deal with .mil shit, civilians just gobbled up crumbs that happened to fall on the floor. When they lost the M110, etc., I guess they were forced to deal with the peons. All I know is tons of KAC is available now when it never was before.
Now I'm curious how these fucking things go on? Part of what makes URX4 so bad ass is the fact it is a once piece part... But if you have a keyed receiver I can see how that'd be better, BUT I can also see it using an expensive proprietary wrench like SR25/URX3. They're not the first to do this, I noticed a Noveske tube I got was designed to key into an upper also but it's not necessary if you don't have it.
So I sorta wonder if that slot is just there so you can change out the gas tube? How else would you access it?
I also see why it's not for sale --without the upper URX6 doesn't seem to be much use. And then the wrench, if it's a two piece then it's gonna have to have a long over the barrel wrench I'm guessing. KAC is also famous for offering proprietary shit that requires you to buy the entire rifle/upper in order to get the magic.
That said, I want one. IF I ever take on 6.5CM it'll be either a Mk20 barrel or an SR25 upper and I'm leaning towards the SR25 here.
Here I thought I was a high speed gear queer KAC fanboy... And in the last week I've been schooled on URX6 and lunchboxes. Take a fucking week off and that's what you get. To be fair though, all my time has been spent tracking down FN vaporware lately so there's that.
I have a URX4 handguard that unfortunately didn't fit my project. But I honestly like the URX6 better.
I have a Geissele super duty upper with a keyed handguard to upper and keyed gas block. I kinda dig where this is going.
I have a Geissele super duty upper with a keyed handguard to upper and keyed gas block. I kinda dig where this is going.
@Strykervet you don't use it to change a gas tube. The gas tube on the E2 Gas System is threaded to the Gas Block which is also threaded and is secured by a locking nut. The entire assembly is accessed and removed through the front of the URX. A special tool is used to remove the unlocking nut. A commercial version is made for sale by D.Wilson, a far more expensive and complicated proprietary version exists as well that is not available.
From what two kac employees have told me it is a visual point to see if gas is leaking when shot. Why they felt the need to add that I don’t know. I would have personally stayed with the one piece design hand guard barrel nut but as I understand it around 200 were released from a contract overrun and those refinements were desired by the customer. So in the future the hex may or may not have that locator tab system.
Why would a customer require that mod is the question. The hand guard was the barrel nut and was torqued down. As is now they have to have a special rod to slide all the way to the barrel nut to loosen. It is a simpler system for Timing.
