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Posted: 12/6/2002 10:33:09 AM EDT
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Hello. I asked about RAS II and SIR all that stuff because I wanted to free float the barrel so I would have an edge when we are talking accuracy. Since I'm topping it with TA31, I thought it would go well with it. (provided that I do my part) I was going to use it on 16" barrel with A2 birdcage FS. Now I've heard that A2 FS does decrease accuracy slightly, unlike phantom and vortex flash hiders that do not affect accuracy. Is this true? If it is, wouldn't this using A2 FS thing offset the advantage gained by free floating the barrel? (Vortex or phantom looks too long for 16" barrel.) Thanks in advance |
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in regaurds to A2, A1 and phantoms; i did a little test once with all 3 types. i was using a wilson 16" barrel that was originally a 20", freefloat HG, flat top and a TA01NSN scope. 100 yard shooting from a bench. the ammo was reloads that were all from the same session, 55gr winchester fmjbt and H335 podwer. A1, scope was zerod with this ammo, groups averaged 1.5 inches. Phantom, no change. A2, groups went 3 inches higher and spread out to about a 3 inch circle. i immediately went back to the A1 to check this out and the grouping was right back to where it should be. i'm no rocket scientist but i know what i saw. .02 |
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TAKE A CLOSE LOOK AT AN A2 AND YOU'LL SEE WHY. THE A2 IS NO WORK OF ART. COL LUTZ OF KNIGHT'S REPORTED HERE ON AR15.COM THAT HE ALWAYS REMOVED THE A2 PRIOR TO DOING ACCURACY TESTING. A FLASH HIDER SIMILAR IN LENGTH TO THE A2 BUT MADE MUCH MORE PRECISELY IS THE KNIGHT'S M4 QD COMP. I GET VERY DECENT ACCURACY WITH THES, AND USE THEM ON ALL OF MY PERSONAL M4 UPPERS. I CAN'T FIGURE OUT WHY, REALLY, BECAUSE IT LOOKS SO MUCH LIKE AN A2, BUT THE M4 QD COMP IS REALLY (!!!) A GREAT COMP. IT'S ALSO A DECENT FLASH HIDER, SURPASSED IN MY EXPERIENCE ONLY BY THE VORTEX AND JUST SLIGHTLY BY THE PHANTOM. WES GRANT [URL]MSTN.BIZ[/URL] |
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Yep that was kind of last straw for me... If I wanted to utilize more of these cool gadgets, it seemed like I needed more of them. So just decided to drop all free floating and modular accessories whatsoever. (excluding some optics and sights directly mounted on upper reciever) Anyways, thanks again for your comments and I will throw some more questions at you later! [:)] |
| Very intersting. I am just now hearing about accuracy issues and flash suppressors. I dont know how these things work to begin with, and like Wes, have no idea how one of them can imporve or degrade accuracy. But like mr_h, I have seen some interesting size groups achieved with the Vortex. It was only after that I read folks claiming Vortex can actually improve accuracy. I dont know nothing about nothing, but I do know that I have been able to achieve sub-mao accuracy over and over again at 100, 200 and 300 yards. All using cheap Winshester Value-Pack ammo (45gr JHP) with a standard Bushmaster 1/9 chrome lined, 14.5" M4 barrel with a Vortex suppressor, SIR, TA31 and JP trigger. It suprised the heck out of me a gun set up like than was able to get such nice groups. Does the Vortex help in the over all mix of things... I don't know. but either way, its staying on the barrel [:D] |
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A FLASH SUPPRESSOR LIKE THE A2 WITH ITS ASYMMETRIC SHAPE AND WHAT APPEARS VISUALLY TO BE RATHER LOOSE TOLERANCES CAN UPSET THE BULLET AS IT EXITS THE MUZZLE. REPLACE IT WITH A VORTEX, WHICH IS TOTALLY SYMMETRIC, AND YOU ELIMINATE THAT. THIS IS WHY FOLKS ARE OFTEN SO PLEASED WITH THE VORTEX WHEN THEY REPLACE THE A2 WITH ONE. THE KAC M4 QD COMP SHARES GENERAL DIMENSIONS WITH THE A2, BUT IS A PRECISION MACHINED UNIT, INSIDE AND OUT. I HAVE ALWAYS HAD GOOD LUCK WITH THEM ON M4'S, IN THAT ACCURACY ISSUES HAVE NEVER BEEN A PROBLEM FOR ME USING THE. BUT I DO ALWAYS UTILIZE DECENT QUALITY AMMO, EVEN IN MY M4'S FOR RUNNIN' AND GUNNIN' DRILLS. HOWEVER, I RECENTLY REPLACED MY OPS INC 2-PORT MILTARY BRAKE WITH AN M4 QD COMP TO TRY IT OUT ON A PRECISION UPPER. LOAD FIVE - SHOOT FIVE - MEASURE FIVE - NO ALIBIS. 0.55" AT 100 YARDS FROM A MEDIUM CONTOUR 18" BARREL. THAT'S AS GOOD AS I CAN DO OFF THE BENCH, FOLKS. (PAUL E'S BETTER.). AND THAT'S AS GOOD AS I'VE DONE WITH THE OPS INC 2-PORT BRAKE. AND WELL WITHIN CRANE'S QUALIFYING ACCURACY FOR THE SPR UPPER. BUT THE POINT IS THAT THE KAC M4 QD COMP DOES NOT DEGRADE ACCURACY. NEITHER DOES THE VORTEX, IN MY EXPERIENCE. NOW, REGARDING FLASH: WE HAD A LONG NIGHT AT AT MID-SOUTH SHOOTING, WITH EVERY CONCEIVABLE MUZZLE DEVICE AND AMMO COMBINATION. WE USED SEVERAL OBSERVERS WITH AND WITHOUT NIGHT VISION DEVICES AS WELL AS VIDEO CAMERAS. #1 VORTEX (CLEAR WINNER) #2 PHANTOM #3 KAC M4 QD COMP #4 A2 (ALMOST AS GOOD AS #3) ... ...WORST: PLAIN MUZZLE AT LEAST MUZZLE BRAKES DIRECT THE FLASH IN CERTAIN DIRECTIONS. THE AK47 POST-BAN WORKED BETTER, BTW, THAN ANY BRAKE AT REDUCING THE FLASH. THE SMITH'S HELPED SOME, TOO. ARMALITE, Y-COMP, ETC... WOW! BUT NOT AS MUCH LIGHT AS THE PLAIN MUZZLE! ONE ADDITIONAL LESSON LEARNED ... NEVER UNDERESTIMATE THE FLASH THAT WILL BE PRODUCED BY CHEAP AMMO. WES GRANT [MSTNBIZ[/URL] |
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I was getting lousy groups with my bushmaster w/A2 suppressor. Then I read in small arms reveiw (AR15 edition a year or so ago) that over torquing the flash suppressor will cause problems with accuracy. I could see why the A2 could be easily over torqued because of the need to line up the solid portion with the bottom. I removed my flashider and reinstalled it making sure I didn't go over the mil-spec recommendations for torque and amazingly my accuracy was vastly improved (I went from 3-4 inch groups to 1-2). Now, could it be better? From what I've read in this post I probably think it could be. Wes, I'm very interested in that M4 QD comp, but I couldn't find it on your website?? Please advise. Edited to add: I did a search on your website and found it. I couldn't find "AR15 parts" and no pics. It looks just like the A2? |
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Mr_H, Tests like the one you performed may not be that valid. The problem is, when you change the various FS combos, you are changing your barrel harmonics, and so the results when using the same ammo (everything else being equal), you are pretty much guaranteed different results. If your ammo is accurate with one flash hider, it most likely will not produce the same results when changing the barrel weight by virtue of a different FS unit, let alone the design change. Side by side comparisons are not accurate, unless you are only ever going to use the same load (commercial lots and not different reloads). If the A2 groups opened up, change your load to produce the same barrel harmonics which has changed since the A2 weighs a different amount. I have a couple rifles with the B.O.S.S. system (a moveable weight and muzzle break combo). I tune the rifle to the load, and not the other way around. Any change in weight on the end of the barrel will detune the setting for a particular load. I must concur, however, that the asymmetrical design of the A2 FS upsets the airflow behind the bullet, and as Wes said, the symmetrical Vortex does not do that. The same effect can happen with a bad barrel crown - if it isn't cut concentric to the bore, and/or unevenly, it will cause an offest turbulence behing the bullet as it exits. I am forced to use the Gem-Tech Bi-Lock on two of my units, but I have never tested them for accuracy compared to other units. I would also like to know if someone gets around to trying, what the results are. I expect the groups to change/shift because the bi-lock's weight is different than the A2, so the barrel harmonics will have changed somewhat. Even chopping your barrel length will cause the same effects... |
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I don't shoot in organized competition, but from what little I understand (feel free to correct me if I'm wrong), CMP & DCM participants use stock A2 flash suppressors on their rifles, and they are regularly shooting ragged little holes at extended ranges. Seems to me that an A2 suppressor is just fine as long as it is not over torqued. |
| Wes, what is the best solution for all the Post Ban folks? I've seen comps with set screws, someone makes a post ban BATF approved thread on comp that uses a different thread size,[url]http://glocksbr.com/axami/shop.php?grd=44 [/url]Looks like OPS makes a 9/16 x 24 thd version in .22 cal. which I assume would be BATF approved for thread on attachment to a post ban AR. You thoughts? |
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NYPatriot, YOU ARE 100% CORRECT. 'SF" TELLS ME THAT THE A.M.U. HAS NO PROBLEMS WHATSOEVER WITH THE A2, EITHER, ON THEIR MATCH GUNS. YET, COLDBLUE TELLS ME THAT HE PERSONALLY HAS QUANTIFIED THE DIFFERENCE BETWEEN RIFLES WITH AND WITHOUT THE A2. BOTH OF THEM HAVE FORGOTTEN MORE ABOUT THE AR15/M16 FAMILY THAN ANY OF US WILL EVER KNOW. YOUR MILEAGE MAY VARY. CS223, THE OPS INC MUZZLE BRAKE HAS NEVER BEEN APPROVED BY THE B.A.T.F. FOR POST-BAN USE. IF IT WERE, A SLIP-ON VERSION WOULD HAVE TO BE DEVELOPED THAT COULD BE PINNED AND WELDED IN PLACE. I DO BELIEVE THAT IF THE B.A.T.F. WERE TO EVALUATE THE OPS INC, IT WOULD BE APPROVED. THE BEST BET FOR POST-BAN FOLKS? LOBBY HARD FOR THE SUNSET OF THE ASSAULT WEAPONS BAN. OR COME UP WITH A WAY TO BUY A PRE-BAN LOWER. WES GRANT [URL]MSTN.BIZ[/URL] |
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Wes: Thanks for the confidence, but I would not claim to have the expertise you have attributed to me. Having said that, I can share what knowledgable friends and associates of mine have passed on to me and my personal observations. The AMU, and most smiths, will tell you that no muzzle attachment will improve accuracy over a full profile unthreaded barrel with a good crown. A barrel with a good flash suppressor or muzzle brake properly installed over a good crown should shoot better than the same threaded barrel without the muzzle device attached. As far as the service rifle with the A2, the unit did not tell me what, if any mods they perform on the A2 suppressor, but the key is getting the bullet out of the barrel flying true and not disturbing it by any physical impingement or gas turbulence back upon the bullet. On the M-14/M-21 series, the NM mods involved boring out the suppressor to ensure the bullet is undisturbed. They did stress the importance of applying the proper torque and using the correct washers when installing the muzzle device. I like the Phantom and the Vortex over the A2 suppressor, and have found that both do an admirable job of suppressing flash down to pistol length barrels, performing much better than the A1 or A2. I prefer the Phantom due to its closed design and the tendency of things to get caught in the tines of the Vortex in the field. I would point out, as a former tactical trigger puller, that the absolute maximum potential benchrest accuracy of the weapon is unrealizable for the average shooter engaging with issue type ammo and combat optics or iron sights from practical field firing positions under stress. In combat, your average rifleman is not going to normally engage targets in excess of 400 m. with iron sights. At that range, 1 moa is just as good as 1/2 moa for me. Current accuracy testing on M193 and M855 ammo in an issue M-4 indicates about 2 moa and 3 moa averages, respectively, so the ammo limitations, the shooter's ability to align the sights with the target (to include windage, range, and other environmental compensation) and release the shot cleanly affect accuracy far more than the type of muzzle device attached, unless it is really botched. While it is technically possible to build a 1/4 moa M-16 series weapon, it involves significant compromises in weight, reliability, maintenance, ammo, and optics. That weapon will most likely have no muzzle device. The SPR has one to attach the suppressor. It would be interesting to see how one would shoot with a clean, crowned muzzle. Wes? Bottom line is that if you are a competitor, or just like to punch tiny groups for fun, the most accurate muzzle device is probably none. Among the other options, I too would be interested in seeing a test among the preban and post ban options (to include the Vais, which I have not seen mentioned on this thread), all properly installed and shot with good control measures. |
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WE'LL GET PAUL E. TO DO THE SHOOTING. I'M NOT BAD, REALLY, BUT PAUL CAN OUTSHOOT ME OFF THE BENCH WITH MY OWN RIFLES. HE'S A MACHINE. ME, I'D RATHER JUST SHOOT TANNERITE TARGETS THAN SMALL GROUPS. THANKS AGAIN FOR TURNING ME ONTO BINARY EXPLOSIVES, SF. WE JUST GOT IN SOME OPS INC 2-PORT MILITARY BRAKES, PURPORTED BY MR SEEBERGER TO ENHANCE ACCURACY IN AND OF THEMSELVES. WE'LL HAVE TO THROW THOSE INTO THE MIX. S/F- WES {URL]MSTN.BIZ[/URL] |
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One last point to add is that there is rarely a free lunch. Gross generalizations follow. There will be superior performers in each group. Bare muzzle is most accurate, but has the most muzzle flash, muzzle climb, and does nothing to reduce recoil (minimal importance w/ 5.56). In weapons of the same overall length, it may have a bit more MV, as the barrel is longer. Muzzle brake has worse accuracy, worse muzzle flash/blast, but the least muzzle climb and recoil. Less MV. Flash suppressor has worse accuracy, roughly the same recoil (by my shoulder), but less muzzle flash and in some cases, less muzzle climb. Less MV as well. Everything is a compromise. Need reduced flash, blast, recoil, or muzzle climb? BPT lose some accuracy and MV. Want the most accurate rifle possible, regardless of flash, blast, recoil, or muzzle climb? Take the plain barrel with a good crown and no threads. Wes: I would recommend shooting a plain barrel of the same manuacturer and quality against the Seeberger, AK type brake, Vais, A2, A1, Phantom, Vortex, maybe a GemTech, KAC or other types you might have, and a threaded muzzle from one of the above. Install all to proper specs. I would use the same threaded barrel for as many of the suppressors and brakes as you can with a thorough cleaning in between. Take an accurate load appropriate for the barrel's twist and use one lot for all testing. Five five shot groups at 100, and possibly another five groups at 300 or so should do it in case the rounds are settling down. If possible, take day photos for blast and night photos for flash. Use a Chrono for MV. That would be super, and would at least help people make informed decisions. |
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Lots of good info here. Just let me add a bit more. I am going to assume that A2 FS on AMU, USMC, etc. Camp Perry rifles have been "qualified". That is to say, are "round" and the bore concentric with al the other inside and outside diameters that relate to the "circle" where the threads are. They may even be bored out a little, in an effort to ensure concentricity. We used to do this with Match M14 FS. Basically, all A2 FS are not created equal. I mean its like a $3.50 part to the government. The only time I'll remove the FS for accuracy testing is when I've mounted a 10x target scope and am using moa ammunition. Using "white box" 55 gr. FMJ and a 4x ACOG or my Elcan, I leave the FS in place, Probablly most important is not over torquing the FS (mentioned above several times). If I was really interested in the "look" and flash suppression, I'd use an A1 FS checked out for concentrity and the old lock washer "hand tight", and perhaps a wee bit more. Then I would check it for tightness between strings of fire. One last thought, even though you may not have a match grade barrel on your rifle, match ammo, etc., when you are "holding & squeezing them", psycholgy (i.e., your level of self confidence) plays a big part on "your guns's" performance. So eliminating or minimizing as many varibles as you can, helps you concentrate on your sight picture and sight alignment, not what "alibi" you are going to use if you miss the bull. ColdBlue sends... |
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