Trying to Pick a Mid Length (or rifle)

**SouthwestAviator** · 08-09-18, 13:56

OP, if you’re looking to spend some money and can’t decide between mid length and rifle length you can split the difference with a Knight’s Armament Co. SR-15 upper. They use an intermediate length gas system, the barrel is also cold hammer forged, and chrome lined. Other improvements include a revised bolt design that is extremely durable, and runs an improved extractor. The uppers ship with an excellent BUIS as well, so consider that when looking at cost.

Of course you can also buy a complete carbine from them and enjoy the fully ambidextrous lower, and good two stage match trigger for not a whole lot more money than the upper alone.

Hm... I'd have to save up quite a bit more for an SR15, as it's $1k+ more than the Daniel Defense and Noveske I'm looking at. It does seem like it's the absolute best of the best, though, which is what I want. Has there been any documented testing to show how much more reliable the KAC with its proprietary parts are than a DD/Noveske/similar? Generally I've wanted to stay with non-proprietary parts but... the KAC is tempting even though it would require more time to get the money on my part. I'd most definitely have to sell the Colt to fund it, and probably other guns too. I would go with the complete rifle if I went this route. Like you said, it's not that much more than just the upper.

Is the KAC SR15 indeed more reliable than other "top tier" mid or rifle length gas system offerings? Has the current model been out long enough to know for sure if it's GTG?

If I decide to go through with this, I want this to be the pinnacle of my AR collection. It won't be the last AR I buy, but I want it to be the best in terms of reliability and durability. I'm not so much concerned with accuracy as it will be a close-up general use/defensive carbine.

Do you plan on using a suppressor with this rifle? If not, take a hard look at BCM ELW profile barrels.

No, I don't plan on using a suppressor with this rifle. I'll take a look at BCM. Good to know about the LW.

**Coal Dragger** · 08-09-18, 14:04

Originally Posted by SouthwestAviator

I've thought about that, but:
-I'm not sure if I would want a lightweight barrel (would it last as long as a gov't profile?)
-Is there some advantage in quality, reliability, or longevity with a Daniel Defense/Noveske/URGI clone over the Colt?

Lightweight barrels are plenty durable, particularly cold hammer forged chrome lined examples.

http://ballisticradio.com/endurance-...c-sr-15-mod-2/

As you pointed out the empirical data from Crane is in, and hammer forged barrels do in fact have a longer service life. The longer service life is particularly true with M855A1, which is evidently very hard on barrels. As someone who has no access to, or need to use M855A1 the extra durability is just a nice value added feature of a CHF barrel.

Realistically there might be some advantages in long term reliability and durability going with one of the options you listed, but your current Colt will devour tens of thousands of rounds before needing to worry about replacing anything other than some springs at normal service intervals. Consider how much $$$ in ammo you’re going to expend to actually burn out that Colt barrel, and ask yourself if you can afford a new barrel after you burned several grand worth of 5.56.

I suspect that you are over thinking this, but that is what most of us on this site are prone to doing (whether we admit it or not).

**SouthwestAviator** · 08-09-18, 17:21

I suspect that you are over thinking this, but that is what most of us on this site are prone to doing (whether we admit it or not).

Oh I definitely am overthinking this, I freely admit. The 6920 is a fine rifle. I might keep it and just use what I pick now as the next AR I buy when I'm able to, if I can be patient enough. I can't explain exactly why I want something "better," it just is what it is. However, if I knew back when I bought the 6920 what I know now (including that the She-Beast wouldn't win the White House), I might have held out for a Noveske, KAC, DD, BCM, or some other mid length or rifle length offering.

I really like the SR-15 a lot and that 20k round documented test is quite impressive, though the proprietary parts and scarcity of KAC armorers seem like potential issues, and they must provide for military needs first. But I'm pretty sure I want my next AR to have mid or rifle gas and a CHF CL barrel, just so there's no room for doubts or "could I have done better". With the recent data from Crane and the adoption of the URGI mid length uppers, I am asking myself that right now.

As I understand it, the Noveske would probably be more accurate while the SR15 would probably be more reliable. I'm not sure where DD and BCM fit into this spectrum.

**grizzman** · 08-09-18, 18:12

Yes, mid-length and rifle-gas systems put less stress on a bolt carrier group than a carbine gas system.

Unless you just want to spend money on a new barrel, I still suggest running the Colt until it wears out, then replacing it with whatever you want, years from now.

What buffer are you using in the Colt? A buffer change can smooth it out some.

**grizzlyblake** · 08-09-18, 19:12

Sounds like when someone trades in their paid for car to finance a new more fuel efficient car in order to save money.

If you're worried about your Colt breaking down you could just buy a second 6920 OEM and have duplicates of everything ready to go.

If you just want a Gucci gun buy whichever BCM, DD, or noveske you like best. There's nothing inherently wrong with just wanting to spend money on a cool toy, but sometimes the self justification is funny

**SouthwestAviator** · 08-09-18, 19:16

What buffer are you using in the Colt? A buffer change can smooth it out some.

Just the H buffer it came with. Ejection is fine. The recoil impulse isn't objectionable and that's not why I want to go to mid or rifle. I'm specifically after increased reliability and longevity. This is not to say that the Colt is deficient, it serves well and I shoot well with it. But I can't ignore that there's better out there nowadays, and there's empirical data to show it that even the military is starting to realize. I used to think mid-length was just marketing hype, but I can't argue with demonstrable evidence.

Really I think a rifle length would be great and I'd prefer it over mid length. It's certainly proven. I just don't see much out there for 18" rifles that aren't geared specifically towards "high speed low drag" race guns other than a Mk12 upper, but I'm not after tack-driving accuracy either and don't want a stainless barrel. And 20" might be a bit impractical for a home defense/general use AR. Otherwise I'd just get a Colt AR15A4 and call it a day.

**grizzlyblake** · 08-09-18, 19:52

How many rounds does it take to kill a 6920? Serious question.

**SouthwestAviator** · 08-09-18, 20:09

From the research I’ve gathered on 6920s the barrel might start losing accuracy at around 8k depending on rate of fire. Many times it’s more. The barrel can be replaced easily (or just get a new upper) and at that point I could go to a mid length. But if there’s some gain in reliability to be had in those +/- 8k rounds by going to mid length now (and as shown by Crane's testing there apparently is), it’s something that I need to consider.

**17K** · 08-09-18, 20:47

If you don't go crazy with mag dumps and train at relatively mild tempo, that Colt barrel will still be shooting fine well after 10K rounds, likely 15K or more.

The big draw to the KAC is the E3 bolt. It's better. No two ways about it. The URX4 is bomb-proof, their new gas block and tube arrangement is unequaled. It's basically a complete system that will last the life of the barrel.

I'd skip Noveske. Their barrels are nothing special and generally quite overgassed.

I've always been a big fan of BCM but the last two I had were gassers (16" ELW BFH).