AR uppers: Del-Ton vs. RRA vs. CMMG??

[nico]

I'm looking to build a reasonably priced 16" midlength AR and have read good things about all of the above, but I haven't seen them compared. I can get an RRA with a chrome barrel for $434 shipped, while the Del-ton upper w/ chrome barrel is $440+ shipping (if I go that route, I'll probably get the rifle kit for $510). The CMMG uppers I've looked at are $525 for a mid or govt. weight barrel.

Based on what people here and on AR15.com have to say, it seems like the CMMG is thought to be better than the other two uppers, but I'm wondering if it's worth ~$100 (after shipping) more than a comparable RRA upper (and which upgrades would be worth getting). I'd also like to know if anyone has had the chance to compare uppers from RRA and Del-Ton, since they're similarly priced.

This will be built on an Essential Arms lower ($77), RRA lower parts kit ($60), and Stag M4 stock ($70). I considered buying an Ameetec lower, but I'd like a Mil-spec buffer tube so I don't have to buy one later if I want to upgrade the stock, and this combination would only cost marginally more than the Ameetec.

Also, does anyone know if the M4 stock that Del-Ton sells uses a mil-spec buffer tube?

 

[Rexrider]

I can't tell you if one is better than the other.

What I can tell you is I am very happy with my CMMG Upper. It is a 16" mid-length, chromed lined, with a govt. profile. Workmanship/quality is top-notch with no problems encountered.

Truth be told, the reason I went with CMMG was because they were the only ones at the time offering a chromed mid-lenght with the govt. profile (that I knew of). Although, I do believe RRA is supposed to be offering one soon. I did some research, found that CMMG was well respected, paid my monies and took my chances.

As I said, I don't know which one is better. I do know that CMMG met my expectations and does what I wanted it too.

Good luck

 

[nico]

Profile is another thing I'm wondering about. The Del Ton and RRA uppers have HBARs. In a 16" midlength, just how much of a difference in feel, handling, etc. is there between an HBAR, mid weight, and govt. profile? As I understand it, the usual idea that a heavy barrel is more accurate/takes heat better doesn't really come into play with an AR?

 

[10-Ring]

I have a RRA complete middy and a 9mm CMMG. Really like the workmanship & performance of both. If $$ is an issue, go w/ the RRA

 

[Ed]

The CMMG is going to have a 1/7 twist meaning you are fine with 55 grain and can shoot heavier. It will be light under the handguards, it will have the correct front sight and be parked under the FSB.

The RRA is most likely gonna do you fine too. I have owned both and now only own the CMMG, of the two. That would be my choice. However, I would get the CMMG without Bolt/Bolt carrier Group and get an LMT both group to drop in. That will run you about $20 more total. I say this because I am not familiar with CMMG bolts and I know LMT bolts are good to go. Carriers properly staked and bolts MP tested.

Understand also that I buy over what I think I will need most of the time.

 

[Gary G23]

The CMMG has 4150 barrel steel and true M4 feed ramps. Well worth the extra $100 IMO.
Stag Arms uses a mil-spec buffer tube. I don't know about Del-Ton, but very few are mil-spec.

 

[nico]

I noticed the difference in steel and the feed ramps. But, from what I've been able to find here and on Ar15.com the M4 feed ramps don't seem to offer much of a functional advantage over regular feed ramps, especially with a mid length gas system. Is there really a difference?

How is 4150 steel different from 4140?

Based on what I've read since I made this post, I'm kinda leaning toward the CMMG.

I'm also wondering about the handling difference between the medcon (medium profile) and govt. weight barrels

 

[Gary G23]

The M4 ramps are more of an issue if you ever use the heavier, longer bullets. My house gun is loaded with Hornady TAP 75grain ammo. I don't want it to fail.
Concerning 4140 vs 4150:
4150 has more carbon content. It is harder, therefore harder to machine, and more costly.
If you never get your barrel too hot to touch it won't make a difference.
If you do however, a 4150 barrel will hold it's accuracy 200 degrees higher than a 4140 barrel. Also throat erosion occurs at a much higher rate on 4140 when your barrel is hot.
If you ever go to black rifle shoot or a carbine class I would definitely recommend the 4150. All three of my AR's have 4150 and M4 ramps.

 

[Ed]

My take on th eramps is if they are there fine, if not fine, but don't dremel them in to make it look like they are there. The anodizing is done for a reason and to cut through it is foolish.

 

[nico]

I just want to bump this thread one more time to give more specifics on my potential builds and hopefully get some more opinions:

Option 1: Essential Arms lower
Del-Ton flat top, midlength rifle kit
YHM fixed rear sight
$625.72 ($668.72 w/ chromed barrel)

Option 2: Ameetec Complete lower
RRA midlength lower w/chrome barrel
same rear sight
$695

Option 3: Ameetec Complete lower
CMMG midlength upper (either medcon or govt. profile) w/same rear sight
$800.90

The prices are all after shipping. I'm leaning toward option 2 or 3 as option 1 is more expensive than I thought it would be, and I'd just assume pay a little more to have the lower assembled and the more known RRA upper. I've also heard very mixed reviews of the DPMS LPK (which comes with the Del-Ton kit).

Everything I've read here and on AR15.com tells me that option 3 would be the best rifle, but I'm still trying to justify the $105 difference in price (vs. spending the cash on ammo and mags). How does the weight (as far as handling is concerned) of an HBAR compare to that of a med. weight or govt. profile (I've heard HBAR vs. govt. is ~9oz)?

There's also the issue of twist rate. For the forseeable future, I'll probably be shooting mostly ~55gr bullets and don't have any plans to shoot heavy/match bullets for at least a few years. I've seen quite a few people say that 55gr bullets should be fine in a 1:7 barrel, but I've also seen quite a few nay sayers. In one discussion, the claim was made that a faster twist is more desirable in a shorter barrel (ie: with 55gr bullets, 1:7 is better in a 16" barrel than in a 20") because the shorter barrel has less distance to impart spin on the bullet. Can anyone shed some light on this? I don't want to spend $105 more on an upper that will be less accurate with the ammo I'll be using most.

On a related note, I know ammo prices are through the roof right now, but is $260 shipped for a case of S&B M193 a decent price?

Thanks for all the replies.

 

[fgr39]

I recently built a Del-ton kit and am very happy with it. I only have about 500 rounds through it so far but not a single issue. It is very accurate and they are great people to deal with. I have not compared it to other makers stuff side by side but have shot a good numeber of AR's and M16/M4's and it is as good as any.

 

[M110]

I built an M4orgery Del-ton kit with a superior arms lower, with thousands of rounds threw it no problem. Good kit, great finish. Match's the lower damn near perfect, with a really tight fit.

I also have a 6.8 CMMG upper on a superior arms lower. I have a hair over a thousand round threw the CMMG again with no problems.


Never had an RRA, so I have no opinions on them.

 

[MrAcheson]

I built my own AR last summer. I used a double star lower, rock river trigger group, and a CMMG upper. I went with CMMG because it was just about the only place I could get a mid-con midlength chrome-lined 1/7 upper with m4 ramps. RRA was hbar, 1/9, and chrome was extra. My only other real choice was to buy the parts and assemble it myself, but then I would have had to buy an upper block and tools. That might have made sense if I planned to make a habit of building ARs, but my wife made it clear that this wouldn't be the case.

In one discussion, the claim was made that a faster twist is more desirable in a shorter barrel (ie: with 55gr bullets, 1:7 is better in a 16" barrel than in a 20") because the shorter barrel has less distance to impart spin on the bullet. Can anyone shed some light on this? I don't want to spend $105 more on an upper that will be less accurate with the ammo I'll be using most.

The shorter barrel, the lower the muzzle velocity, so the slower the bullet will spin with the same twist rate (if you assume the bullet is spinning at the same rate as the rifling). But generally the bullet isn't moving/spinning so much slower that this will really matter that much.

I'm very happy with my CMMG. My gun shoots cheap American Eagle 55 grain ammo very well, even with the high twist rate. With cheap store-bought M193, you can't expect match accuracy in the first place. You might be lucky and get it, but you can't expect it. I'm pretty sure that the shooter is the least accurate part of my AR system at the moment.

I haven't run any of the heavier ammo through it, but I wanted the make sure my gun could do it. Buying the right barrel the first time is a lot cheaper than buying another barrel, wrench, upper block, etc in a year or two when it turns out I want to shoot heavier stuff. You aren't likely to shoot that barrel out in a year.

is $260 shipped for a case of S&B M193 a decent price?

How big is their case? That's really good for 1000 rounds. You can easily beat it if they mean 500.

 

[Bartholomew Roberts]

All three are good choices and I don't think you would be disappointed with any of them.

Everything I've read here and on AR15.com tells me that option 3 would be the best rifle, but I'm still trying to justify the $105 difference in price (vs. spending the cash on ammo and mags).

AR15.com tends to define "best" as closest to the military specifications. The main differences I can think of between the CMMG and RRA are the CMMG has M4 feed ramps, parkerized under the front sight base, 4150 instead of 4140 steel, different barrel profile and 1:7 twist instead of HBAR and 1:9.

Now whether those differences are worth $105 is only something you can decide.

How does the weight (as far as handling is concerned) of an HBAR compare to that of a med. weight or govt. profile (I've heard HBAR vs. govt. is ~9oz)?

A 16" HBAR will be in the neighborhood of 2.7lbs. A 16" medium weight is around 2.4lbs. The 16" Gov't profile mid is just under 2.2lbs. I have a medium contour CMMG midweight and it handles very well.

There's also the issue of twist rate. For the forseeable future, I'll probably be shooting mostly ~55gr bullets and don't have any plans to shoot heavy/match bullets for at least a few years. I've seen quite a few people say that 55gr bullets should be fine in a 1:7 barrel, but I've also seen quite a few nay sayers. In one discussion, the claim was made that a faster twist is more desirable in a shorter barrel (ie: with 55gr bullets, 1:7 is better in a 16" barrel than in a 20") because the shorter barrel has less distance to impart spin on the bullet. Can anyone shed some light on this? I don't want to spend $105 more on an upper that will be less accurate with the ammo I'll be using most.

I have never seen a 1:7 barrel spin apart a 55gr bullet in any length. Generally, you have to get into very lightweight (40-45gr) and very thin jacketed varmint bullets.

As for less accurate, I've never seen any proof that the 1:7 is less accurate than the 1:9 with 55gr in either my own shooting or in the shooting of others that I have witnessed. My guess is that if this difference even exists, it is so small that few shooters can appreciate it. To give an example, if someone told me greasing my bullets with whale oil would reduce my groups by 0.05" - I wouldn't ever be able to answer this question because my own personal error is greater than 0.1" even in the best conditions.

Haven't bought any 5.56 ammo lately (still living off my reserves of Guatemalan) so I couldn't say on prices.

 

[nico]

The more I think about it, the less I think the CMMG is worth the money for me. M4 feedramps, 4150 steel and parkerizing under the FSB all seem like relatively superficial differences, and spending the extra money on a lighter barrel in a gun that'll get the vast majority of its use at the range doesn't make sense to me.

I didn't notice this before, but I can get a stainless barrel with a .223 Wylde chamber and 1:8 twist for $20 more with the RRA upper. Based on what I've read, the Wylde chamber seems like a good upgrade and the 1:8 twist seems like it'd be a little more versatile than a 1:7 or 1:9 (better for heavy bullets than 1:9; better for lighter bullets than 1:7). Is there any reason not to get the stainless? Does the stainless offer any advantage over chrome-lining (or is the opposite true)?

 

[Bartholomew Roberts]

Sounds like you have a good understanding of the tradeoffs to me and good reasoning as well.

I didn't notice this before, but I can get a stainless barrel with a .223 Wylde chamber and 1:8 twist for $20 more with the RRA upper.

Those are nice barrels and very accurate. My favorite rifle has a medium contour stainless steel 1:8 Lilja with Wylde chamber.

I'm on the fence on chrome-lined v. stainless steel myself. I don't really have enough data to give a good opinion. From what I can tell, a chrome-lined barrel doesn't really have much additional barrel life over an SS barrel. They both seem to resist corrosion well with even minimal maintenance. The SS barrel seems to give better accuracy; but some chrome-lined barrels can shoot very well. The chrome-lined handles heavy firing schedules, throat erosion and high heat better; but as Zak Smith's ITRC reports show, a stainless barrel can definitely be run hot.

 

[nico]

Yeah, I found a few of Zak's threads in my searching. To say I'm jealous of his guns and the fun he gets to have with them would be an understatement.

I have one more question (I hope) that has come to mind: The guy selling the Ameetec lower on AR15.com is offering an upgrade to an H-Buffer for $15. I realize that the H-buffers are generally used in guns with carbine length gas systems to reduce bolt speed, and I haven't found any discussion of using them in a midlength. My understanding is that the bolt speed in a midlength is slower than the carbine, but still faster than with a rifle length gas system, with the rifle length system generally being thought of as being the best (assuming the barrel is long enough to allow the proper dwell time). Would an H-buffer in a midlength serve any purpose, or am I just overanalyzing minor details?

Thanks for all the replies, especially Bartholomew. This thread has really helped me figure out what I want, and saved me some money.

 

[Soybomb]

I love ar threads here...I learn so much without getting tactical all over my clothes.

 

[nico]

lol, stay away! Black Rifle Disease is chronic and has no cure. All you can do is treat the symptoms by buying guns/crap to hang on it/ammo

 

[Gary G23]

Buffer selection depends on three things (at least):
1. Length of gas system (as you have already mentioned)
2. Type of ammo used
3. Which bolt carrier you use. Some bolt carriers are heavier than others which affects the timing. Enhanced carriers are heavier than standard carriers. M16 carriers are heavier than enhanced AR-15 carriers.

My mid-length works 100% with a M16 bolt carrier and a heavy buffer. BUT I use full charge ammo (Winchester Q3131). If I were to use Wolf or some other underpowered ammo it might not function as well.

 

[Bartholomew Roberts]

Gary covered it well. I used to run an MGI Rate Reducing Buffer in my carbine (7oz.) When I went to a midlength barrel, I started getting constant short-strokes with .223 PMC ammo and even the occasional short stroke with 5.56mm ammo. I switched to the standard carbine buffer and the problem stopped.

Now the MGI buffer is almost twice the weight of the H-buffer, so I don't think you would have any problem running an H-buffer. Having said that, the carbine buffer is working just fine for me so far and I have around 2,500 rounds down that rifle in its first year. I've run the rifle on full-auto hard (back to back mag dumps) as well with a standard carbine buffer and it had no problems there.

If you plan on using a suppressor in the future, the H-buffer might help handle the increased backpressure better. If you plan on using really underpowered .223 ammo (even worse than Wolf), then the H-buffer might be a problem.

 

[nico]

I'll mainly be shooting middle of the road ammo. I'm looking into getting a case of S&B M193 in the next week or so. If that falls through, I've found a good price on Black Hills Blue Box, but it's back-ordered right now. I don't plan to use wolf.

I'm pretty sure the RRA uppers come with an AR15 carrier with shrouded firing pin. I think I might just get it. If there are any issues with it, I don't think it'd be too hard to find someone willing to trade for a standard carbine buffer.