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Posted: 7/6/2005 9:40:43 AM EDT
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The Recon/RECCE concept appears to be based upon a desire to balance portability with accuracy. So, how light can a RECCE upper be built and still maintain sub-MOA accuracy? Based upon my bolt-gun experience with .22 centerfire cartridges, it seems to me that it wouldn't take a truck-axle of a barrel to produce very good accuracy. Any feedback on weights of specific examples would be appreciated. Pics are very helpful of course. It seems to me that the barrel contour would be the greatest contributor. It also seems to me that fluting should be a viable means of achieving a larger-diameter barrel (i.e., stiffer) without paying as severely in the weight department. Beyond the barrel, I guess the FF tube, optic/mount, sights, muzzle device... all add up to a total that is more or less portable. |
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A super light barrel can be very accurate if you only need to shoot one 5 shot group. But even an HBAR will warp if you smoke 300 rounds through it and then try to shoot a group. So you've got to decide how much thermal abuse you want your barrel to withstand and still maintain a certain level of accuracy. ETA- Also note that fluting will leave more residual stress in the barrel than a plain contour. The ABS barrels look promising. |
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When I was at ABS yesterday I was holding a 16" HBAR with Carbon wrap and I think it weighed less than 2 lbs. When talking with Mike D. he told me that you can shoot 30 rnds as fast as you can through this barrel, then grab the carbon part on the barrel, and it is warm or cool to the touch. Matt |
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Affordability would be nice too. That being said, the carbon fiber barrels do seem promising. I have a fluted HBAR (not turned and fluted) that I have thousands of rounds through. It was my first and only AR for years and when I take to range, I shoot the sxxx out of it. Doesn't seem to string much and cools much faster than M4/lwt profiles. I also have a precision rifle that is fluted too and it pretty much hangs around .5 MOA when I can suck it up and sandbag and everything else I can think of to hold it steady. Plus it has a 2 pound trigger, not your typical AR trigger which makes a HUGE difference. Anyway, so far, I'm kind of a fan of fluting. Would it make a difference to do the Colt type testing of a fluted barrel to insure integrity? 'Course, by the time you get done with the turning, fluting and testing, you probably are almost at the cost of the carbon fiber setup and still won't have as good a barrel... Maybe sucking it up and paying for the ultimate, lightweight, accurate, durable product is the only way... It usually is. |
I'm sure that each maker has an opinion on this. Click here for Dan Lilja's FAQ, which indicates that he doesn't believe fluting to induce stress. In fact, he states that "fluting can and will relieve stress if it is already present." ETA: Shilen, however, is opposed to fluting, because "a barrel can induce unrecoverable stresses that will encourage warping when heated and can also swell the bore dimensions, causing loose spots in the bore." |
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Of course, I would certainly recommend the ABS barrels, and I use them in my quick-change-barrel gun, so that is a definite for me. But, looking at the rest of the RECCE package, it seems waaaayyyyy too long of a FF tube and rail system. I mean, how much rail does a person need? There's a mile and a half of it on there. You could probably chop off a pound of weight by just making the railed FF tube the normal carbine size. Also, it makes no sense to me to go to the extent of having a FF tube to ensure a free floated barrel, so that the sighting is not affected by handguard pressure, and then move the sight post to the handquard! The front sight belongs on the barrel. Another thing is these buttstocks are getting out of hand. Some of the more popular collapsible buttstocks are weight in at over a pound! One of them is almost 2 pounds! I've been working on lightening things up for our MGI project gun, and here are some of the more productive things to lighten weight: ABS Carbon fiber barrel saves about a pound Carbon fiber FF tube saves about a half pound Old school Fiberlite collapsible buttstock saves a quarter pound or more(depending on what you had on there before) My gun completely battle-ready, with a full mag, HBAR profile carbon barrel, MGI quick change system, Aimpoint CompM with cantilever mount, KAC vert. grip, M16 carrier, RRB heavy buffer, steel BUIS front and rear sights, big latch charging handle, Insight Technologies weaponlight, and complete sling and attachments, ready to go, weighs in at just a hair under 8 pounds. If I remove the optic, weaponlight, KAC vert grip, and mag, it is under 5.5 pounds with the irons still on it. I think with the upcoming carbon fiber FF tube for my QCB system, it will be under 5 pounds dry. If I go to some experimental titanium springs and titanium hardware, I think I can get it down to about 4.5 pounds dry. And this is with an almost half-pound buffer, and a heavy M16 carrier, and an HBAR profile barrel, with iron sights on a flattop. That would put a loaded, battle ready AR15 in your hands at about 7 pounds loaded, with optics and accessories on it. Not bad. It's all the stuff that you load on to the gun that really kills it. My advice is to limit the size of the FF tube and rail space to an absolute minimum, use a minimalist buttstock, and use carbon fiber where you can. Don't hang any more crap on the gun than you absolutely need, and select the optics and accessories for the lightest weight ones that will still provide necessary functions. |
The Recce generally has an optic as the primary sighting device, and a set of BUIS if the optic should fail. The long tubes are for bracing/grasping and guarding against burns, and cover the gas block, so a normal FST is out. |
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Zak, I see that is the idea with the RECCE system. Truthfully, I think it is overkill with the rails, and an unnecessary weight burden. However, I'm just me, and basically if someone else really wants that long rail, they can still use the other methods to reduce the weight on the rest of the gun to partially compensate for the added weight of the RECCE rail out front. My main issue is that the more weight out front you have, the handling of the gun is slowed, and the balance is not as good. I used to like the weight out front, because I liked the muzzle flip reduction from the heavy muzzle, but after I discovered how to keep the action speeds under control, and how to control the secondary recoil impulse from the moving masses in the action, then I didn't have any muzzle flip to worry about anymore. So, I could then use a very light front end, and not sacrifice controllability. Yes, this did require a heavier buffer(RRB), so in effect I moved about an additional 4 ounces of weight back into the buttstock, but it allowed me to use a lighter muzzle, which I thought was a good trade. Overall, I saved a pound in the barrel, and added 4 ounces to the buffer, and the overall tradeoff was saving 3/4 pound, improving handling, and improving controllability and reliability, better accuracy, and super thermal management. I guess you could say that I used the weight where it would do the most good, and saved it where I didn't need it anymore. Of course, each person has their own set of requirements, but those are mine. I don't like to hump any more weight than I absolutely have to, and I like the gun to shoot like a squirt gun with practically no recoil or rise. And I always use some kind of optic as a primary sight too, so I have to compensate for that with weight reduction elsewhere. |
heh, you beat me to it... but yea.. my recce should be as light as possible without sacrificing accuracy/durability... i'll be getting an ABS Barrel... |
twl, If I had to really pick one.  Of all the RECCE format weapons I have, this one (6.8 in the rear) and its 5.56MM twin are the lightest by far. The ones with longer rails (12-13.2') have other advantages, such as bipod stability etc over these, but they all are VERY Sub-MOA, if I do my part. 
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Pcurtis, Those are some nice looking guns. I tend to be an accuracy nut myself, since I have long been into benchrest shooting, and I love accurate weapons. As you have on your guns in the photo there, I like the rails to stop before the FSB. To me, that is enough rail, and keeps things light while still providing function. |
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On fluting... Realize that the guys that produce the BEST barrels cant agree as to whether it helps or hinders accuracy. Most fluting is so shallow that the weight savings is very small. Why introduce another variable if you dont get much return. In order to realize any significant weight savings you have to flute the hell out of a barrel. I have found that fluting will help with balance or "feel" though. Ive had both fluted and unfluted barrels shoot well. And if fluting causes a 0.5 moa barrel to shoot 0.75 moa (a 50% loss in accuracy!) are you gunna notice except off the bench? If fluting was done poorly, Im sure it would negatively impact accuracy. Of course if the fluting was done poorly, its probably a good guess the crown aint stellar either - this will definitely impact accuracy. Zak, is on the $ when he says the skinny barrels will be affected by heat sooner than a thicker barrel. If you go skinnier go shorter to gain stiffness. Also remember that the heat generated by a 22 lr is ALOT less than a 223. More heat = more metal movement = bad. On weight...and CF barrels The carbon fiber barrels (fiber over quality barrel blank) if successfull will be the shit. For example I compared an 18 inch SPR countoured CF barrel to a 16" Stainless recce contour and the CF barrel was 8-9 oz lighter (yes I weighted them on a real scale but I cant remember the exact amount). Figuring that fluting a 'good' steel barrel will up the cost $75-150 you will actually spend less on the CF barrels. I havent had a chance to really hammer the CF barrel but the initial impression is that there will be alot of used steel barrels for sale if the trend continues. I hold final judgement until I get a chance to really abuse one. I think the polymer uppers and lowers currently available commerically are shit. Yes, they are lighter, but Ive personally broken lowers where the buffer tube screws in. This all happened when a large distributer invited me out to "check these things out" and it happend in less that 200 rounds of commercial ammo. Granted these WERE NOT MADE OF CARBON FIBER. If they can build Lance Armstrong a winning bike that weighs nothing (3 pounds or less, iirc) then a durable upper and lower should NOT be impossible out of CF. Now, the question is can they make one that can be priced competatively with AL. receivers? My guess is not yet, but I think we'll see 'em get close in the next few years. The combo... Probably the best doable option is a 16 or 14.5 inch CF barrel, A3 upper, a polymer lower (with aluminium/steel reinforcements in/at critical areas) - Never seen one but I wouldnt think it that hard to produce. glock and springfield arent having any trouble... Use a doctor optic for your red dot (1-2 oz.) - that saves over a trijcon/eotech/aimpoint with a base significantly. Hell if you cant save almost a pound going with a doctor and CF barrel I'll be supprised. Now as suggested shorten you HG. I think a carbine length too short and a rifle length while very nice probably longer than needed. Go with a FF'd mid length. You'd have to weigh both metal and CF HG's and see which is lighter. Currently I think troy back-up sights are the lightest (but this is my subjective opinion - I cant recall weighing them). Aluminum barrel nut and gas block. This will combo if used, even without any special, not produced yet receiver(s), will save you weight . Then you can get anal and start removing dust covers, drilling holds in pistol grips, etc. Personally, I think Ti to be too expensive for the weight savings, but you could follow that route as well. Like TWL said, its amazing how a superlight rifle becomes a boat anchor once you add all the 'stuff' on it. |
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twl, The reasons that many of us run long float tubes with sights attached to the rail: Long float tubes give more room to rest the rifle on. They make it harder to burn yourself. Flip front sights do not obstruct the optic, and don't block the targets hands. That said, I am looking into an A4 upper with a 10.5 inch barrel and a 9.0 LaRue rail. Won't be that heavy. P.S. Could you use a Pac-Nor blank to build an ABS barrel? Have you read about Noveske's barrels? I am certainly excited by them. |
Depends on your uses... add in an extended eye relief scope or a PEQ-2 in front of the optic and you can run out of rail quick on a carbine. Besides that the extra rail is nice in keeping hot barrel off of flesh during training.
A full size DD tube weighs in at 13oz. A mid tube weighs in at 10oz and a carbine tube weighs in at 8.5oz. The KAC tubes are heavier but most of that is due to the steel barrel nut which means that a carbine tube will still not weigh that much less than a mid or full-size tube.
I agree with you here; but don't think the difference is dramatic enough to be a major issue.
To my mind, where the weight is can be more important than what the weight is. An extra 8oz in the stock of a gun "feels" a lot less tha 8oz forward of the barrel nut. Some of those stocks can actually be beneficial in that they return balance to a gun with a lot of weight forward. For guys running a suppressor you are talking a minimum of 18-20oz out at the very end of a long lever. Even with a very lightweight barrel, you will still need to counterbalance that suppressor with a heavier stock in back to get good balance.  |
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Sorry I was out for awhile, and didn't realize all this was happening here. Some of you make some great points about the uses of the longer rails, and weights of things like the buttstock for balance. Maybe I'm just getting tunnel-vision because of the project I'm working on now to save weight. Combat Jack, Yes, a Pac-Nor barrel can be used with our carbon fiber system. In fact, we're doing a Pac-Nor SS polygon-rifled barrel with the carbon application right now for an ARFcom member. It takes a bit longer for this, because Pac-Nor takes 4 weeks to get us the blank before we can even start with our work. DevL, I haven't used the M93 stock, but from all I've heard it is a very solid stock. I agree that weight isn't everything. Like I said, I'm probably too absorbed into this weight saving project right now. Bartholomew Roberts, That is one heckuva nice looking midlength, sporting that ABS carbon fiber barrel on it! The tan one is nice too! I'm jealous because I only have carbine system barrels for my gun right now, and no midlengths. |
Now I just have to get a chance to shoot it. The DD 9.0 rail is freakishly light. I know for a fact it is lighter than the KAC 7.0 FF-RAS it replaced and I suspect it is lighter than the C8 handguards on the tan one. Combined with that ABS barrel it definitely changes the handling of the gun. |
It is my understanding that the purpose of fluting is not for weight savings but for barrel cooling. While the fluting may only save a little bit of weight, it helps a lot in keeping the barrel cooler. |
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WHO SHOOTS A GAS GUN GUN FASTER THAN JUST ABOUT ANY MORTAL? TARAN BUTLER, USPCA 3-GUN TACTICAL CLASS NAT'L CHAMP TWO YEARS RUNNING. WHO BUIDS TARAN'S UPPERS? MSTN ARE THESE UPPERS LIGHT IN WEIGHT? YES. WHAT CONTOUR DOES TARAN SHOOT? LONGER RANGE MATCHES - MSTN'S 17" WITH FULL LENGTH GAS SYSTEM SHORTER RANGE MATCHES - MSTN'S 16" WITH MID-LENGTH GAS SYSTEM COMPASS LAKE BUILDS THESE BARRELS FOR US IN 1X8" FROM BOTH DOUGLAS AND LILJA BLANKS. WE HAVE SOME FLUTED FORWARD OF THE GAS BLOCK, TOO. YES, THEY ARE "VERY SUB-MOA!" IF RESULTS, RESULTS LIKE NATIONAL CHAMPIONSHIPS, ARE WHAT YOU ARE AFTER, NOT JUST HYPE, THESE UPPERS, WITH PRI'S CARBON FIBER FORENDS & ALLOY BARREL NUT (THE LIGHTEST FOREND, PERIOD), MAKE THE ULTIMATE LIGHTWEIGHT, FAST SHOOTING, PRECISION UPPER. WES GRANT M.S.T.N. |
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Cgv69, It depends which 'source' youre getting fluting knowledge/wisdom from (and what theyre selling! - Thanks WES for your update on Mr. Butler and the commerial break) whether they use the cooling or weight arguement. In either case I have seen very little DATA that was statistically significant on the cooling aspect. Most of the "data" has been subjective reports - we see this kind of crap all the time in the gun world. Thankfully, we have more sources for good info than the gun rags. The weight issue is really minor as it applies to saving much of anything, but I will say that fluting can make a noticeable difference in balence and 'feel' of a rifle. Personally, I find this pretty important but that's just me personally and others mileage may very. |
gunslingerdoc, I do have to agree there is a lot of conflicting “facts” about barrel fluting. What it’s benefits are, what issue it can potentially cause, etc.. I think anybody interested in it should read whatever they can, from as many different sources as they can, and make up their own mind. The theory’s I’ve read as to why fluting increases a barrels cooling ability make sense to me. Not being the scientific type, I do not really have the time, ability or interest in proving or disproving the theory. Weight is another issue and as you’ve noted, while you may not loose much weight (as measured on a scale) from fluting, you can feel the difference in your hands. In hand feel is what matters most to me. So if you add those two things together then fluting = a good thing in my boat. Does fluting make a significant difference in weight reduction and cooling? I can’t give you a scientific answer but if I can notice the difference in a positive way then that makes it worth it to me. As far as fluting causing a negative effect on accuracy. I've never seen anything compelling enough to make me think it does and I'm not a good enough shot to likely notice anyway  So for me, I'll take mine fluted... YMMV |
| Fluting should increase the barrel's ability to cool. Increasing the surface area of the barrel in contact with the environment will help dissipate heat better. This is why the radiator in your car or AC unit has an arseload of metal fins with the coolant lines running through them. The greater the surface area, the more air in contact the hot bits and pieces to soak up heat. |
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I agree that fluting "should" increase cooling, but 6 or 8 flutes wont make a barrel as efficient as a radiator with hundreds of 'flutes'. Yeah you'll get more surface area, and on the surface it follows that more surface area = more area to dissapate heat. However, that's assuming that all areas dissapate heat at the same rate at a constant rate. I would argue that the fluted areas will dissapate heat differently that the nonfluted areas. Ive even seen the arguement that since the fluted areas (being thinner) heat faster and therefore heat up the nonfluted areas between the flutes. Im too far away from college physics to bother to do the math. It doesnt matter to me. The other thing to remember is that flutes on a barrel are not (yet) subjected to a fan that blows fresh (read cooler) air down them. Theyre stuck under a handguard subjected to the same air mvt or lack there of as the rest of the barrel. Again, fluted or not it really doesnt matter for weight or cooling, but will help the "feel" which has a great deal of value to myself and others. Now if it shaved 8-10 oz. off then ALL of my barrels would be fluted! |
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