AR15 CQB carbine configurations, wich is "best" ?


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686+
May 25, 2008, 01:43 AM
I am looking at putting together a 16 inch carbine with an adjustable stock.

I see that the options for configurations are gas block with sight, or just a picatiny rail. Upper reciever in a flattop or with a carry handle.
I intend to put a red dot scope on the carbine, but not sure if mounting it to a handle, so it's high up, or to a flattop so it's low is best.

Also, what about barrel type and weight? Any drawback to thin barrels other then accuracy reduction? M4 profiled barrels, what does that do for me?


Please share your experiance and tell me what worked or seemed better.
Thank you.

686+

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possum
May 25, 2008, 01:51 AM
i prefer and use a flattop carbine, as you say mounting an optic on the handle will be to high up. it will work but it is much nice and gives you a much better check stock weld moounted on a flatop.

my first are was a a2 model and i sold it to get a flattopand have been happy ever since.

as far as red dots my favorite are eotechs, but you can't go wrong with a aimpoint or even c-more sights are nice and low profile.

i personally run my ar with the front sight base on the carbine, so if the red dot goes down i just flip up the buis and go to it, or worse case scenario i can use the eotechs screen as a big ghost ring sight and the front sight post which works at ecqc egagements.

haveing a flip down fromt sight will keep it out of your sight picture while not using it, but if the iron sights are needed then you will have to flip up the front and back to get them in use.

Bazooka Joe71
May 25, 2008, 03:41 AM
Possum pretty much summed it up...Flat top w/ an eotech and BUIS is going to be your best CQB set-up...With a light barrel.

Jenrick
May 25, 2008, 03:56 AM
Dominator mount : http://www.rockriverarms.com/index.cfm?fuseaction=category.display&category_id=318

If you ever need to go to your irons you will probably not have time to deploy non-fixed BUIS. A dominator or similar mount gives you fixed irons that you can immediately transition to. If my EoTech goes down, I just mash my nose forward and down to the charging handle, I'm, back in business. Same reason I like fixed stocks, one less thing to mess with when it hits the fan. Probably going to eventually go to a 1.5 or 1x ACOG so I don't have to even mess with turning my EoTech on, just grab and go.

Far as barrels go, heavy barrels have a couple of things going for them. More mass so the heat up slower, more mass so they are harmonically more stable, more mass so with the above the shoot better. Please note the difference in how well a h-barrel and regular barrel shot is probably a non-issue for anything under a couple of hundred yards. As you stated this is for CQB, there's only one thing a heavy barrel has over a thin barrel, and that's it'll take more heat to burn it out, meaning more rounds down range in an engagement. As we're not in Iraq, it's probably a moot point.

A thin or stepped barrel is much lighter. This means it's easier to keep up and ready, and IMO points faster.

My work rifle is a 16" RRA regular contour barrel, fixed stock, flat top with a dominator and an EoTech on that. Zero'd for 50 yds, that gives me a maximum of +/- 2" out to over 200yds. Put the donut on the center of mass pull the trigger, need precision put the dot on the hair line pull the trigger.

-Jenrick

possum
May 25, 2008, 04:33 AM
joe brings up a good point, if you want to keep it light weight, and since it isn't gonna be used for a precision rifle, a thinner lighter weight barrel is another good choice.

also i am sure that at some point you will like to have a sling of some sort. i suggest a 1 point sling but that is my personal preference.

JWarren
May 25, 2008, 08:48 AM
Couple points to possibly consider...


Lately, I am seeing some interesting discussions of EO Techs on AR15.com's optics area. Some seem to crap out more often than one would like:

http://www.ar15.com/forums/topic.html?b=3&f=18&t=379348

http://www.ar15.com/forums/topic.html?b=3&f=18&t=369513

http://www.ar15.com/forums/topic.html?b=3&f=18&t=374769

http://www.ar15.com/forums/topic.html?b=3&f=18&t=378942



I am not so sure about single point slings either. They are a pain in the butt if you have to "carry" they weapon slung on your side.

I'll take a two point.



-- John

briansmithwins
May 25, 2008, 09:31 AM
My setup:

Barrel: 16" CMMG lightweight midlength barrel. I like the midlength gas system as it is not as violent as the carbine length gas system . 16" because I don't want to have the flash hider welded on or pay ATF $200 for the 'privilege' of having a 14.7" barrel.I like the fixed FSB as that's on less thing to go wrong.

Receiver: Flattop upper receiver and standard A2 lower. No fancy double set triggers. I'm just not convinced that the accuracy gained by a 'fancy' trigger is that significant compared with the case of ammo I could buy to practice with. Stock is a fixed A1. I'm not that tall (5'10") and the A1 fits me better. Adjustable stacks are nice, but mostly seem to be something else to fiddle with and are more delicate than a fixed stock. I do use a MIAD pistol grip with the replacement bolt core as that's a spare I like having on the rifle.

Optics: flattop receiver with Aimpoint ML3 (2MOA dot), Aimpoint 3X magnifier on a Larue pivot mount. Troy flip up rear BUIS. I agree with the earlier post that a fixed rear BUIS is better, but with the magnifier there isn't room for one. Also have a look at the Larue fixed BUIS, I used one before I went to this configuration and it works very nicely. With the Aimpoint and magnifier I can gets hits fast from contact to 400 yards.

I've run this configuration for a few local practical rifle matches and at a class. It works for me. As for Eotechs, I've seen 2 rev F units die while shooting. Replacing batteries didn't recover them but leaving the batteries out overnight did. That's not a lot of failures for the amount of people I've been around that were using Eotechs, but it always sucks when it happens to you.

BSW

JWarren
May 25, 2008, 09:38 AM
I went with a 16" barrel for the exact same reasons, Brian.


-- John

possum
May 25, 2008, 09:49 AM
brian,
what type of batteries were you using when they pooped out on you?

i have a "aa" model and i have found if i use lithium batteries they last longer and the heat from high rd counts and extended training courses do not have the effect on the eotech like regular "aa" batteries.
i able to go 2 days at a training course with the lithium batteries, and i replace them after each 2 days of training. that has seemed to have worked for me.

briansmithwins
May 25, 2008, 10:15 AM
I use 1/3N lithium batteries in my Aimpoint, same battery for the 2 years I've had it. I generally don't turn the Aimpoint off as I figure the switch is more likely to fail with a quoted battery life of 5 years...

I think one of the Eotechs was a CR123 model, I'm not sure as they weren't mine. Also, replacing the batteries did not get them running for the match, the shooters had to transition to irons.

BSW

sundance43.5
May 25, 2008, 12:17 PM
I find the removeable carry handle to be useless. I have 3 AR's, and the only one with the handle still on it is my Colt 6920. I just like the way it looks stock from the factory.

Since you specified a CQB type rifle, I would recommend that you look at a
14.5" barrel with a permanently installed flash hider, to meet the 16" requirement. While it sounds like you're still getting a 16" rifle, the gun is actually 1.5" shorter overall, because 16" barrels still have the flash hider added on, adding 1.5" or so to the overall length.

Also, Sabre makes a very nice 14.5" upper with a mid-length gas system, which many believe increases the gun's reliability. This is the upper that's going on my 3rd AR.

Link to the Sabre from a great company:

http://www.pkfirearms.com/store/get_item.aspx?id=1443&action=display

Under the "PK Custom Uppers" link, there is the same upper, but with your choice of a railed fore-end.

DMK
May 25, 2008, 01:05 PM
I agree with what the others said here. Keep it simple. Think: light, handy, reliable.


Midlength gas system

Flat top upper

Red dot sight mounted low and forward.

Backup iron sights that will always be available in case a battery dies or something. (I went with folding rear sights, but I always leave them up)

Lightweight, pencil profile or Govt. profile, chrome lined barrel, 1/9 twist (1/7 twist if you want to shoot 75gr or 77gr bullets)

Standard handguards to save weight up front

Simple flashlight mount.

Good quality flash suppressor (Phantom or Vortex)

Simple single point or two point sling. Single point basically serves like a handgun lanyard, use a two point of you want to carry the rifle.

Good quality USGI mags (Labelle, D&H, etc)



http://mysite.verizon.net/dmk0210/myarms/Midlengths.JPG

possum
May 25, 2008, 03:19 PM
I use 1/3N lithium batteries in my Aimpoint, same battery for the 2 years I've had it. I generally don't turn the Aimpoint off as I figure the switch is more likely to fail with a quoted battery life of 5 years...
I think one of the Eotechs was a CR123 model, I'm not sure as they weren't mine. Also, replacing the batteries did not get them running for the match, the shooters had to transition to irons.
roger got it thanks.

Bazooka Joe71
May 25, 2008, 03:27 PM
OK, I don't think this would be a thread hijack, as it is relevant to the OP's question:

What are the advantages of a 1x power aimpoint opposed to an eotech? I've owned both and I can't see why anyone would want an aimpoint(1x) over an eotech.

briansmithwins
May 25, 2008, 03:52 PM
Aimpoint advantages:

1) 5 years battery life- that's with it ON 24/7/365. I don't like optics that eat batteries, before Aimpoint came out with these I was pretty much using tritium lit scopes.

2) Simple- 1 control, no auto off.

1 and 2 are enough for me. That was before I watched Eotechs die during a rifle match.

BSW

taliv
May 25, 2008, 04:12 PM
What are the advantages of a 1x power aimpoint opposed to an eotech? I've owned both and I can't see why anyone would want an aimpoint(1x) over an eotech.

are you serious? the eotech absolutely sucks. having to use both hands in a very awkward position to shut it off is just ridiculous. plus, it can automatically shut off when you need it. plus, the battery life just stinks. plus, it's prone to failure. plus, their reticles stink. plus, the "it's faster because of the FOV" arguments are not compelling.

i got one before i was well-read on the subject and put it on a class III gun that i rarely use simply because of aesthetics. the guns i shoot all have aimpoints or acogs.

Bazooka Joe71
May 25, 2008, 06:06 PM
are you serious? the eotech absolutely sucks. having to use both hands in a very awkward position to shut it off is just ridiculous. plus, it can automatically shut off when you need it. plus, the battery life just stinks. plus, it's prone to failure. plus, their reticles stink. plus, the "it's faster because of the FOV" arguments are not compelling.

Um, well yeah I'm pretty serious, but thanks for asking...

Not that it matters what you have to do to turn it off(since you aren't pressed for time), but if you need two hands then something is wrong.:confused: You must have teeny tiny hands, because my left thumb turns the eotech off with ease.

24/7/365 for 5 years is a very nice feature, but I've never had a problem with the battery life...Especially if you just keep extras on hand...I've changed mine once and that was because I left it on over the winter and didn't do any shooting.

I know opinions are like, um, well, you know, but I think the eotech's reticle is way, way better.

With all that said, give me an ACOG anyday.



Just my .02.:)

TexasRifleman
May 25, 2008, 06:08 PM
are you serious? the eotech absolutely sucks. having to use both hands in a very awkward position to shut it off is just ridiculous.

Well to be fair, you shouldn't be somewhere urgent if you are turning it off :)

As for it shutting off when you need it, it stays on for 8 hours. If you're in combat nonstop for 8 hours you have bigger problems than the Eotech battery :evil:

taliv
May 25, 2008, 06:24 PM
i'm 6'5" with fairly large hands. my thumb easily covers both buttons, but i can't press both at the same time.

you guys can make excuses all you want, but the fact remains that you don't need to turn an aimpoint off, and if you want to turn it off, you can do so with one hand. and that's just one of the "advantages of a 1x power aimpoint opposed to an eotech" that you asked about.

there are all kinds of reasons you could be under time pressure without people shooting at you. or, you might be on the back porch and simply not want to put the cold beverage of your choice down in order to turn off the sight. :)

and there are plenty of reasons you might want to leave it on longer than 8 hrs. for instance, if you have a truck gun and want to pull it out to take a shot at a coyote or something. the extra 2 seconds it takes to turn your sight on is a lifetime.

Jenrick
May 25, 2008, 06:32 PM
taliv: Not sure having to use to hands to shut off the EoTech is a bad feature, I've never found a need to do so in a non administrative setting either. Edit: just saw you're answer about having big hands. Fair enough reason :)

On the overall EoTech vs. Aimpoint question:
You're going to here a lot of pros and cons on each platform, a lot of opinions and pure nonsense too. Me I personally prefer the EoTech. However I will admit the Aimpoint has several advantages already listed, such as battery life and control simplicity. However just like your weapon, checking your sight is ready to go before you go on patrol, the range, on a mission, to class, etc can make up for a lot of things. Turn your sight on, check for the low battery indicator, etc. Make sure to turn your sight off, and double check that it's off before stowing it. Worried about it auto-offing at the wrong time? Use the up arrow to turn it on, that'll set it 8 hour auto off, with 8 more hours after another button press.

I think the reports of EoTechs being less durable etc. are the normal result of everyone and their brother having a story of a guy they know. Just like Glock KB's, sure they happen, sure there are people with legitimate accounts, but overall it's a lot less frequent then it's reported to be. There are a lot of EoTechs and a lot of Aimpoints in service out there. Everyone I've talked talked to that used either sight, had no problems with theirs. This ranges from multiple tours in Iraq with a LOT of direct action experience to taking a 2 day AR class with a sub 1K round count.

Find which one is more comfortable and works better for you, just like a firearm. The one YOU shoot the best is the better option.

Back to OP's question on setups: Stay away from quad railed handguards. They add a lot of weight for very little gain. Let's look at realistically what you NEED to stick on them for CQB work. A sight if you're going for the scout rifle setup and a light source. That's it. All the rest that you can mount on the handguards: front grips, lasers, IR lasers, laser designators, shotguns, grenade launchers, tasers, etc are just candy (or mission specific). So worst case is you need two rails, if you're putting your sight on the receiver you don't even need that. Other then the sight nothing on the rails needs to be held at a true zero, the light etc can wander a bit with no harm. I would recommend using normal handguards with add on 1913 rails that just attach to the handguard in the ventilation holes. Much cheaper and lighter weight then a full railed hanguard. A good weapon light such as an M-3 or TLR-1 will hold up just fine and is cheaper then the an "AR Specific" weapon light. For about $65 you can get the remote tail cap assembly and switch, so for about $170 you now have a fully adjustable weapon light system on your AR compared to $300-700.

Also stay away from flip up front sights. If you're optic goes down and you have a fixed front sight post you can shot using just and your optics shell as a gigantic ghost ring. Sure you're probably not going to be making hostage shoots at 200yds, but it'll work for what you need at close range. No front sight post, you're just doing instinctive shooting. Flip up sights are great if you're using a magnified optic mount on a quick release, as you can pop off your scope, deploy your irons and go in that building. You have some time in this case (possibly only 30 seconds, but that's a lot) where as in a building you may not have time, space, or the motor ability left to get them deployed.

Slings
Single Point Pros:
Cheap
Easy to setup, especially if your rifle has an attachment plate already
Easier to transition to off hand side with sling on body then other options
Single Point Cons:
Releasing your rifle without trying to guide it somewhere can result in a rather painful whack in the pelvic area.
Normally requires some method of securing the rifle to the side if you want it to stay on the side rather then hang down in the middle
Can be very awkward to run and maneuver with you're rifle hanging straight down in front of you.

Two Point Pros:
Cheap
Easy to install
Traditional
Can be used as a shooting aide how fancy you get with it is up to you (hasty sling all the way up to slinging in high power style).
Carries the weapon very well in a multitude of carry positions
Two Point Cons:
Having the sling setup to allow the rifle to be deployed with the sling still on body makes it awkward to move with the rifle as you'll have a lot of slack in your sling.
Very difficult to transition to off hand.
Depending on how you carry the rifle slung, deploying it can make the sling come off body completely preventing you from releasing your rifle and still retaining it.

Three Point Pros:
Can allow easiest offhand transition if you get a good one that's designed for it
Keeps weapon over to off hand side of the body when slung
Allows you to maneuver and run with the rifle slung much better then a single point, and better then several of the two point variations.
Cons:
More expensive usually
Most complicated to setup


I like a three point as it puts the weapon across my body favored to the left, side clearing my sidearm when I release my rifle. Single points work well too, they just don't put the weapon out of the way as well. Two points can work very well as well. Look at what you need out of your sling and go from there.

-Jenrick

taliv
May 25, 2008, 06:51 PM
I think the reports of EoTechs being less durable etc. are the normal result of everyone and their brother having a story of a guy they know. Just like Glock KB's, sure they happen, sure there are people with legitimate accounts, but overall it's a lot less frequent then it's reported to be. There are a lot of EoTechs and a lot of Aimpoints in service out there. Everyone I've talked talked to that used either sight, had no problems with theirs. This ranges from multiple tours in Iraq with a LOT of direct action experience to taking a 2 day AR class with a sub 1K round count.

I don't suppose you were aware that the SOPMOD PMO "strongly recommends not using [eotech] until they can be replaced or repaired." ?
or that "The SOPMOD PMO has ordered a halt on any further fielding of this item until sufficient testing has been performed on sights with the incorporated part upgrade. " ?

http://www.ar15.com/forums/topic.html?b=3&f=18&t=369513&page=1

i recommend reading up on that as it's recent and relevant. some choice quotes include:

"The initial failures occurred at 1,500 round on the low end and 7,500 rounds on the high end. "

which explains why thousands of internet users aren't seeing the problem and falsely reporting there is no problem...

" we run a 52 man class during the first 2 weeks we had 16 out of 52 shut off multiple times while shooting no matter how much you scraped the battery terminals. "

more later...

Jenrick
May 26, 2008, 12:11 AM
Yeah I had seen that, read it on that arf thread posted by JWarren.

Not saying that there's not a problem. Not saying that this specific one about non-spec battery terminals isn't a legit issue either. I am however saying what's the failure rate, what models are affected, is it a specific range of SN's within a specific model, or is it a wide spread issue, etc.?

I stated that I feel that the incidence of there being a problem is lower then it's commonly held to be. Same as with Glock KB's. Everyone knows about it, everyone knows someone who knows someone. How many people have actually had that problem, or can put me in direct contact with someone who has had that problem?

I personally know 3 guys on another agencies SWAT team that put well over the high end failure numbers without any failures. A gentleman I work with served in Iraq as a Recon Marine, and his EoTech never went down on him. He liked his enough that he's getting one for his work AR after the Corp wouldn't let him take the one he used in Iraq home. So what does that say? That I know 4 people who have put a lot of rounds down range that didn't have a failure. Statistically that means nothing. Same with there being about 15 people on ar15.com who claim to have had problems.

Again I'm not saying there isn't a problem. Making it out to be that all EoTechs are POS and WILL fail is overstating it in my opinion. If there were hard numbers or at least model or SN specifics I might be more inclined to believe it was a wide spread problem. As is it appears it's most likely several models that are not normally purchased by civilians (I'm not paying the extra $$$ for NV comparability I'll never use), and even then there's no info on what model or manufacturing time frame this affects.

Obviously the suckers have worked just fine for a while, as they even made it into the SOPMOD project in the first place. I understand some people just plain don't like them, that's fine. Apparently there's a manufacturing problem currently, I don't think that invalidates the whole design.

-Jenrick

MT GUNNY
May 26, 2008, 12:14 AM
The only thing I will add to what all have said is get rid of the stock hand guards make that barrel float!

possum
May 26, 2008, 01:02 AM
eotech pro's.
65 moa circle which is approx the size of an average man at 100yds. used for range est. also great as a ghost ring for cqb.

1 moa dot for more precise shooting if needed. cover 3" at 300yds instead of the 12" with a standard aimpoint.

hash marks at the 3, and 6 oclock are great fror leading.

also the eotech comes with the intregal mount. so you buy a $350 sight and the mount comes with it unlike the various aimpoints for the same cost.

as far as needing 2 hands to turn off that makes no difference like the other posters have already said.
btw dependig on what button you push for the eotech to come on depends on how long it stays on, they do turn off automatically after a certain ammount of time. 6 or 8 hours depending on the button you use.

jrfoxx
May 26, 2008, 05:29 AM
FWIW, I have my red dot mounted on the carry handle of my M4, and comparing it to mounting with the handle removed, I find being on the handle more comfortable and natural for me, as the scope comes up right in front of my eyes, with my head close to staright up, which is faster, more natural, and more comfortable for me.

But, as you can see, the VAST majority of people feel the opposite, so I'm apparently just wierd (that is not new information to me, either.It's been noticed before.:D). Try one on the carry handle if you can without spending any $$, or at minimun, get a cheap $8 handle mount to test and see what works. maybe your a freak like me.:p

Bartholomew Roberts
May 26, 2008, 01:19 PM
I thought briansmithwins outlined a pretty nice rifle if you don't want the NFA hassle. I do like the adjustable stocks though since it can be handy for everything from wearing a ton of gear to teaching others how to shoot.

I would recommend using normal handguards with add on 1913 rails that just attach to the handguard in the ventilation holes. Much cheaper and lighter weight then a full railed hanguard.

The DD 7.0 with aluminium barrel nut is actually lighter than M4 double-heat shield handguards with a GI barrel nut. The DD 9.0 with aluminium barrel nut is the same weight as plastic handguards. Other handguards that are within a few ounces of that are the DD Lite and Larue.

Not sure what a picatinny section weighs; but handguards and picatinny are going to be close in weight to the above named rails. The handguards will be cheaper; but the rails will free-float the barrel, offer better cooling, give a more stable attachment point and offer more versatility.

You certainly don't have to have one to do what you need to do; but depending on your needs and wants, it might be worth the extra expense.

I see that the options for configurations are gas block with sight, or just a picatiny rail.

Like most choices, this has a lot to do with personal preference. Some shooters find that even with two eyes open, a fixed front sight post obscures part of the view and prefer to run with a flip front. However, if the red dot fails, they will be slower to transition to irons. At close ranges <25yds you can just center your target in the dead optic and that will work will enough on IPSC targets to let you finish without transitioning to irons. The other issue with Picatinny gas blocks is that most are set-screwed and are more likely to come loose than a pinned gas block (although it usually requires some fairly hardcore shooting to shift even a set-screwed gas block). If your gas block shifts on the barrel, you now have a straight-pull bolt action. On the other hand, there are pinned lo-profile and picatinny gas blocks out there.

For people who aren't comfortable with the centering the optic trick at close range, using your dead optic like a large ghost ring with a fixed front sight, will let you make hits out to about 50yds on an IPSC target.

Some people aren't comfortable even with that and run fixed rear and front sights with the red dot so that they can transition to irons through the dead optic. If you do this, be sure to sight the irons AFTER you have mounted the optic.

On slings, I either run a single point or a two-point like the VCAS or VTAC slings. Zak Smith has a good article on slings somewhere that is worth reading.

Jenrick
May 26, 2008, 03:25 PM
Bartholomew: Thanks for the info on the light weight 1913 rails, have to look into that. Have you found any advantages to having the barrel free floated for close range work? I've thought about doing it myself to have the extra accuracy at long range, but haven't really figured out a benifit at close range? If I decided to go with a full rail setup I'd do it, as I might as well if I'm gonna mess with it at all :)



Zak's article on slings:
http://demigodllc.com/articles/tactical-slings/

I'd recommend poking around Zak's sight in general to anyone that hasn't been there, he's got a lot of good articles.

-Jenrick

MHBushmaster
May 27, 2008, 03:51 PM
I decided to Free Float my "fighting" carbine because you can never really predict the range at which you will need to be shooting.

Sure, a free float offers only a miniscule accuracy advantage at close range, but it also helps with cooling the barrel off faster which is something to consider when using a pencil profile barrel.

I also like that with a FF rail I can easily mount/use a Forward Vertical Grip, or even a bipod if so inclined, attach a light, and have my Eotech extend out over the HG when mounted in the forward most rail on the upper receiver (with M4 Handguards the front of the Eotech 552 and 512 won't have enough room to clear the handguards as the M4 style have more girth; with older/slimmer CAR style handgaurds its no problem).

Bartholomew Roberts
May 27, 2008, 04:31 PM
Bartholomew: Thanks for the info on the light weight 1913 rails, have to look into that. Have you found any advantages to having the barrel free floated for close range work?

Not really, at least not in terms of accuracy. The rails keep the overall firearm cooler; but the rails themselves get hotter than plastic handguards if you run them hard. However you can add rail covers to the sides (or a vert grip) and still get good cooling while keeping the handguard cooler.

For me it was mainly a case of the free-floated rails being only a tiny bit more expensive than the non-free-floated. So I went ahead and got them. They are handy when shooting for accuracy and seemed to reduce my group size in general by about 0.5" at 100yds.

H2O MAN
May 27, 2008, 04:37 PM
I picked up a Colt LE 6920 and added a LaRue 7.0 hand guard for when and if I wanted to run a VFG or other accessories.
I currently run a light weight configuration with the original CAR stock and carry handle - irons only.

ArmedBear
May 27, 2008, 04:55 PM
Does accuracy loss due to a hotter barrel matter AT ALL for a CQB carbine?

MaceWindu
May 27, 2008, 05:00 PM
Does accuracy loss due to a hotter barrel matter AT ALL for a CQB carbine?

...no...

Mace

ArmedBear
May 27, 2008, 05:07 PM
Didn't think so....:)

I've put all my shots right where I wanted with a skin-searing hot Mini-14 barrel at CQB ranges, and those who have shot Mini's know what kind of groups a really hot Mini-14 shoots...

It probably makes more sense to focus on stuff that matters, then.:)

Bartholomew Roberts
May 27, 2008, 06:31 PM
Does accuracy loss due to a hotter barrel matter AT ALL for a CQB carbine?

The point of a rail for close-in dynamic shooting isn't that it helps accuracy at that range. It is that the rifle stays cooler and heat is a killer of rifle parts.

An added plus with the longer rails is that they also help with "barrel branding" by keeping that nice, smoking hot barrel from leaving a good scorch mark on you or your gear.

MarcusWendt
May 28, 2008, 01:09 PM
Very informative thread. It's been over 20 years since I had an M-16 in my hands. So much has changed.

So kind of getting back to the spirit of the OP's post, it seems that most folks prefer flat top and BUIS with some type of optics.

My rifles are for defense and a little fun only. I shoot handguns more often, but I feel that it's a good idea to have a few long arms on hand.

For a larger caliber or longer range need, I've purchased an M1A Standard. I really like it. It's proven, basic, and fairly simple. I use Iron sights for the time being.

Now, like the OP, I need something that's more CQB oriented. I like the KISS principle so from what I've gathered in this thread I'm looking at a ( CA legal) 16" AR with either fixed or adjustable stock. It does seem flat top is the way to go leaving options open for later. Fixed front post with flip up rears? Possible rail for a light? Good Mags, quality and supply. Anything else I'm forgetting?

I'm leaning toward Stag or M&P at this time.

Jenrick
May 29, 2008, 03:29 AM
A sling, a sling is a holster for your rifle basically. Without one your are dedicated to having to use at least one hand at all times on your rifle.

-Jenrick

686+
May 31, 2008, 01:00 AM
Thanks for all the feedback.

You have given me more to think about than I thought possible. I need to go down to my local pusher and see what the various setups feel like and will go from there.

Thanks again.

RevolvingCylinder
May 31, 2008, 07:12 AM
For the fixed carrying handle, it depends on how much you like them. You could always get one of the mounts that mount your optic in front of the carrying handle. I've found that heavy barrels don't balance particularly well(very front heavy). The quality and speciifations of the barrel is what is going to be the biggest factor of accuracy of the barrel itself. Just start it with a minimum of accessories and add them as you learn more about them.

To give my own perspective on Aimpoint and EOtech comparisons:

My firsthand experience with the Army's M68 Aimpoints is that they're not the most durable(seen one break firsthand dropping onto a floor from ~2 ft up) Internally their function of the elevation and windage screws(or whatever you want to call them) can also unreliable(unresponsive, or "sticks") too making sighting in very aggravating. They also have reticles that I have found to be excessively large for their purpose and they tend to "bleed"(not a crisp clear dot) for me. The exposed and too easily turned knob gets turned a lot on its own too(for instance getting in and out of cramped, armored HMMWVs) which mean at any given time I can look through it I've found it off when I left it on and left on when I turned it off earlier because of this.

Because I found I couldn't trust the Aimpoint nor make it work to my satisfaction I spent my own money on an EOtech. As for durability, my EOtech wears some serious scars from all the beating it takes. I find the controls easy to use and predictable. I just turn it on and I know just how long it will be on. If I need it on longer, I can just "refresh" it when it's convenient. It's wide FOV and crisp MOA dot has made it the quickest and easiest to use red-dot I've ever used. It's even made in America where the Aimpoint isn't. The only thing the Aimpoint has over the EOtech is battery life(even though the EOtech lasts pretty long on standard AAs) but the EOtech uses standard AAs which are very coomon, even around here. It also changes batteries quicker and easier than I've seen in any other device(lift a lever, dump the battery carrier and stick two fresh ones in and close the lever).

TheDisturbed1
May 31, 2008, 08:22 AM
What if the CQB situation goes beyond closed quarters... effectively and consistantly hitting a target at 50-75 yards (if the target gets that far) could use a dissipator upper.

Not to mention the things look mean... With the xtra handguard length you could mount an Anti-ICBM battery on side. :p

TexasRifleman
May 31, 2008, 08:42 AM
which explains why thousands of internet users aren't seeing the problem and falsely reporting there is no problem...

If our sights are not failing then they we not "falsely" doing anything.

My Eotech has survived for years, including a couple of carbine classes of over 1000 rounds in a weekend. My SBR with the Eotech probably has close to 10,000 rounds. I mean, read what you wrote. Thousands of users are not seeing a problem, yet we're lying when we say we haven't seen the problem?

I don't suppose you were aware that the SOPMOD PMO "strongly recommends not using [eotech] until they can be replaced or repaired." ?
or that "The SOPMOD PMO has ordered a halt on any further fielding of this item until sufficient testing has been performed on sights with the incorporated part upgrade. " ?

I notice you didn't include the fact that it's only the model 553, the one that uses the Lithium batteries. Just as many people are using the 552 to take advantage of the lower cost AA batteries, at least in the civilian world. There is no problem with that model and this PCN does not apply.

And in case you have never lived in the real world, this kind of thing happens all the time when a subcontractor changes a part. The inherent design of the 553 is not at issue here, it is that a subcontractor provided a different battery contact and that contact has a design problem.

In the real world, not the high speed low drag world of the Internet, contractors face PCN (product change notice) issues like this all the time. They get fixed and people move on.

By the way USSOCOM did choose the 553 over other optics and will continue to issue them after the PCN is put in place. This is how it works in the real world. You won't find a government contractor that has never had a PCN issue of one kind or another.

And of course it's stuff like this that should make you not even consider any kind of flip up front sight. You want to be able to move to the backup immediately if there is an optic problem. Flip up rear fine, but leave the front post in place.

686+
June 4, 2008, 10:10 AM
So what rate of twist should be choosen for a CQB. I see that most things are 1:9, but there is some 1:7 barrels available. Which to choose?

MK11
June 4, 2008, 10:23 AM
What can you afford to shoot? Some people say 1:7 gives you the broadest range by shooting 55 decently and thriving with the heavy stuff. But I don't know how much sense it makes to zero your rifle and practice with "cheap" 55 grain stuff and then load 77 grain for defense. For personal defense, 55 grain loads probably work as well as anything else.

Bartholomew Roberts
June 4, 2008, 02:17 PM
1:7 shoots everything from 45gr to 77gr accurately (though if you are a top notch shooter and shooting from a stable position, 1:9 has a slight (less than 0.5" at 100yds) accuracy advantage with the lighter rounds.

1:9 is more common and shoots everything from 40gr to 69gr accurately. Some 1:9s will also shoot 75-77gr quite accurately; but my experience has been that:

1. You are right on the margin of accuracy and you may lose stability with a temperature drop or similar change in environment.

2. If you happen to be unlucky enough to get a 1:9 that does not shoot 75-77gr well, it will still be capable of doing 4-5" groups at 100yds which is practical for most defensive uses.

ArmedBear
June 4, 2008, 02:20 PM
What if the CQB situation goes beyond closed quarters... effectively and consistantly hitting a target at 50-75 yards (if the target gets that far) could use a dissipator upper.

I play around with a carbine at 100 yards. Not a problem, even standing offhand with A2 sights. As Bartholomew Roberts said above, I'd be more worried about touching a hot barrel.

But the dissipator doesn't make it cooler, it just keeps your hands off it.

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