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Posted: 5/3/2026 9:40:02 PM EDT
[Last Edit: OWCH][Edited]
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I know nothing, only what I've been told and I've been lied to most of my life. What is this muzzle device? Pictures below... Its on an m82a1 Sn under 500. Is it factory or no chance? Early a1 with old 82 part? I looks so puny to be effective. Thoughts? Google results were no help Thanks jp ETA 7/14 https://youtu.be/hlAW2zvf29c?si=bKrE8cN11pKJThzd |
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Originally Posted By osprey21: Like this? early M82A1 brake - circa 1989 https://i.postimg.cc/hjJ7KfgZ/early-barrett-m82a1-brake.jpg That's it. Thank you. Is it effective for muzzle blast or should be upgraded? . Thanks again. Jp |
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Originally Posted By OWCH: https://www.ar15.com/media/mediaFiles/34290/1000014132-3757229.jpg I thought i had. I was interrupted by turmoil, our Bison Bull decided to go ape shit on a 5 hour old calf... ( calf is somehow alive this morning) Jp It was also used in conjunction with the bolt carriers with the short throw accelerator in the bolt carrier. If you upgrade to the arrow head brake, you need the newer style bolt carrier that has a longer throw accelerator and accelerator rod. The cone brake was also on the longer 33" barrels with the large flutes. That barrel most likely does not have a chrome lined chamber. |
I hated going to weddings. All the grandmas would poke me and say "You're next". They stopped that when I started doing it to them at funerals.
Sic semper evello mortem tyrannis
Sic semper evello mortem tyrannis
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Originally Posted By 50cal: Thats the brake before the arrow head brake came into being. It wasn't really that effective. It was used on rifles made before 1989 or so. The arrow head brake came out not long before the Desert Storm era rifles. It was also used in conjunction with the bolt carriers with the short throw accelerator in the bolt carrier. If you upgrade to the arrow head brake, you need the newer style bolt carrier that has a longer throw accelerator and accelerator rod. The cone brake was also on the longer 33" barrels with the large flutes. That barrel most likely does not have a chrome lined chamber. Thank you for that good to know information .( bolt carrier) Me thinks I'll fire it as is and see how I feel about it. Then see about carrier and brake options with cost.  Thanks again every one. JP |
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Reading about the short throw accelerator in the bolt carrier. It suggests that short throw accelerator in the bolt carrier is conducive to use with a suppressor. Vs the long throw, which slowed timing and made the rifles punch to a push feeling. That accelerator redesign along with the muzzle device change, tamed recoil down quite a bit. So my next question is, does the m107 design have a long or short accelerator that enables use of a suppressor? Or is the m107 just completely different In design.? Jp |
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Originally Posted By OWCH: Reading about the short throw accelerator in the bolt carrier. It suggests that short throw accelerator in the bolt carrier is conducive to use with a suppressor. Vs the long throw, which slowed timing and made the rifles punch to a push feeling. That accelerator redesign along with the muzzle device change, tamed recoil down quite a bit. So my next question is, does the m107 design have a long or short accelerator that enables use of a suppressor? Or is the m107 just completely different In design.? Jp It's not long a long or short throw piston system.its a good idea to get the newer style battery bumper and impact bumpers for the barrel The older guns have the 2 narrow bumpers on the barrel. You will also need the fatter impact bumper that goes between the barrel key and barrel stop in the upper. The M107 isn't that radically different from the regular 82A1 rifles. A lot of cosmetic differences. Few internally differences. Those older rifles do need a headspace check. The manufacturing differences between the bolt and barrel extension make it a wise decision to check headspace. |
I hated going to weddings. All the grandmas would poke me and say "You're next". They stopped that when I started doing it to them at funerals.
Sic semper evello mortem tyrannis
Sic semper evello mortem tyrannis
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Originally Posted By 50cal: The short throw accelerator is not condusive to the use of a can. You will beat up the gun trying to use a can in that gun under that configuration. It's not long a long or short throw piston system.its a good idea to get the newer style battery bumper and impact bumpers for the barrel The older guns have the 2 narrow bumpers on the barrel. You will also need the fatter impact bumper that goes between the barrel key and barrel stop in the upper. The M107 isn't that radically different from the regular 82A1 rifles. A lot of cosmetic differences. Few internally differences. Those older rifles do need a headspace check. The manufacturing differences between the bolt and barrel extension make it a wise decision to check headspace. Rifle received.. I purchased new a bmg field gauge. The bumpers you speak of, will be next. The paper manual i got with has newer version of m82a1 than this is. First question,( view my pix). Is it assembled with old bumpers in correctly? I can't seem to find a pic of an upper orientated to show inside upper.. If anyone can post one then I can correctly install new style bumpers. Reinstall barrel and muzzle device and check headspace. Rifle came with an l&s 10x40 m3a Dated 87 with barrett reticle. Thanks in advance. There doesn't seem to be much finish wear on moving parts. Jp  
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Messing around after seeing bumpers on barrett website. Seeing the flat side on them, I took barrel off and found the bumper orientation was wrong. I spun it around and everything went together. Question Are these bumpers OK to run sum rounds with till new ones arrive? And I'm understanding that if I installed new style muzzle device, I must replace carrier to new design first?    Thanks again jp |
| That is the old short throw carrier. If you get the newer brakes, you need a newer style carrier where the accelerator throws further to the rear. |
I hated going to weddings. All the grandmas would poke me and say "You're next". They stopped that when I started doing it to them at funerals.
Sic semper evello mortem tyrannis
Sic semper evello mortem tyrannis
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Originally Posted By 50cal: The short throw accelerator is not condusive to the use of a can. You will beat up the gun trying to use a can in that gun under that configuration. It's not long a long or short throw piston system.its a good idea to get the newer style battery bumper and impact bumpers for the barrel The older guns have the 2 narrow bumpers on the barrel. You will also need the fatter impact bumper that goes between the barrel key and barrel stop in the upper. The M107 isn't that radically different from the regular 82A1 rifles. A lot of cosmetic differences. Few internally differences. Those older rifles do need a headspace check. The manufacturing differences between the bolt and barrel extension make it a wise decision to check headspace. @50cal Question along these lines…is it possible to buy the necessary parts to use the M107A1 brake and suppressor on any of the M82’s (ie…carrier swap)? |
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This is not professional advice and anybody who undertakes any of these mods does so at their own risk and accepts that they are voiding the Barrett factory warranty for any damage caused by shooting an M82A1 suppressed with a QDL. With that liability disclaimer out of the way..... My experience is that you can get most of the parts you need to update an M82A1 to run a QDL suppressor successfully. There are a few parts Barrett may not sell you, if they did they would probably be cost prohibitive, and IMHO they are probably not really needed. The primary mechanical differences between the M82A1 and the M107A1 are outlined below. One thing to keep in mind is that not all M107A1s are the same and there have been changes/updates to the M107A1 over its life. 1. Muzzle Brake The 2-Port "Arrow Head" on the M82A1 vs. the 4-Port "Shark" brake on the M107A1. Obviously, you need to swap the Muzzle Brake over to the M107A1 design if you want to run the QDL. You can buy the M107A1 brake from Barrett or other vendors online. Its pretty straight forward to swap over, but its not exactly cheap either at ~$400. 2. Barrel Spring Key to Trunnion Impact Bumper. This is the polymer impact bumper "tube" that slides over the barrel and goes between the trunnion and the barrel spring key that slots into the barrel. The M82A1 impact bumper is much shorter than the M107A1 impact bumper (1.375" vs. 2.") The shorter M82A1 impact bumper allow the barrel on the M82A1 to reciprocate much further rearward vs. the M107A1. The longer impact bumper on the M107A1 reduces the amount of energy that the reciprocating barrel can impart onto the the bolt group as it effectively short strokes the reward travel of the barrel compared to the M82A1. This piece appears to be important in controlling the bolt group velocity on what may be a less efficient M107A1 muzzle brake design unsuppressed. The M107A1 muzzle brake probably does even less in term of recoil reduction when the QDL is installed as the suppressor blocks off all the ports on the muzzle brake. This larger M107A1 Impact Bumper part is sold by Barrett (you have to call them to get it as its not on their website) but its pretty cheap (~$50) and is easy to swap out when you do the muzzle brake swap.  3. Barrel Reciprocating Springs These are the two springs that allow the barrel to reciprocate rearward to make the action function and drive the barrel back forward into the trunnion. These springs also control how much energy the reciprocating barrel imparts into the bolt group as well. On the M82A1 it take about ~40lbs to fully compress the barrel to bottom out on the impact bumper and trunnion. The latest generation M107A1 barrel reciprocating springs take over 90+ lbs to fully compress the barrel to bottom out on the impact bumper and trunnion. (on the 20" barrel variant) Keep in mind its also 90lbs to compress the barrel to the impact bumper and trunnion over a much reduced barrel compression distance compared to the 40lbs on the M82A1 with a longer barrel compression distance. The older versions of the M107A1 have barrel reciprocating springs which are similar to the M82A1 springs and take about ~40lbs to fully compress but again at less compressed barrel distance of the M82A1. When I spoke with Barrett they suggested older generation M107A1 owners update their barrel springs to the latest 90lbs variants if shooting suppressed with a QDL. The updated M107A1 barrel reciprocating springs are available on Barrett's website and are (~$40) and are relatively straight forward to swap out. However you are going to need a wrench to get a firm grip on t the spring key to reinsert it into the barrel as its very difficult with just your bare hands to reinsert the barrel spring key back into the barrel slot with the new twice as strong springs installed. The M107A1 has a hole in the spring key you can use the rear takedown pin as a leverage tool that the M82A1 doesn't have. I presume you could probably mill an identical hole in your M82A1 spring key if you wanted to use the takedown pin as a leverage tool or just just a wrench for leverage on the key like I did.  4. Recoil Spring This is the recoil spring that drives the bolt group back and forth in the rear of the receiver and which holds the buffer. The M82A1 spring is slightly softer than the latest M107A1 spring. When I asked Barrett about this they mentioned that have changed the M107A1 recoil spring design a couple times over the years but that all the recoil spring variants across the entire lineup are very similar. The latest M107A1 recoil spring is available from Barrett, it is cheap (~$25) and easy to swap out on the M82A1. Its probably not a real critical part but if you are ordering everything else from Barrett why not get the latest updated M107A1 recoil spring.  5. Buffer The M82A1 has a polymer buffer with no steel "over-compression" sleeve. The older M107A1s have a very similar design polymer buffer to the M82A1 but also have a steel "over compression" sleeve that the older M107A1 polymer buffer nests inside. This steel over compression buffer sleeve is what limits the rearward travel of the bolt carrier if the buffer was to compress too much. The steel sleeve limits the carrier recoil stroke and prevents the charging handle from impacting the rear of the charging handle slot in the receiver protecting both the charging handle and receiver charging handle slot from damage. It may also protect the recoil spring from being 100% compressed as well. The latest M107A1s have a hydraulic buffer that goes inside an identical steel sleeve. The hydraulic buffer is available from Barrett but its not cheap (~$500). Its easy to install along with your new recoil spring. When I spoke with Barrett they also suggested older M107A1 owners exchange the polymer buffer for the hydraulic buffer if shooting an older M107A1 suppressed.  6. Bolt Group The main difference between the M82A1 and the M107A1 in terms of the bolt group is the "Bolt Lock" design. The Bolt Lock is the part that locks the bolt head forward once it clear the trunnion so the bolt head stays in the extended and properly rotated position for the duration of the bolt group reciprocating back and forth within the receiver. If there wasn't a Bolt Lock mechanism the bolt would collapse into the carrier when the carrier bottoms out on the receiver during the recoil stroke and/or when attempting to feed a round from the mag. If the bolt head was collapsed into the carrier the bolt wouldn't be properly lined up to re-enter the trunnion. The M82A1 the Bolt Lock design is a spring loaded lever design on the top of the carrier that snaps down behind a cutout on the top of the bolt head and is depressed (freeing the bolt to rotate) by the steel ramp in the top of the upper receiver as the bolt group begins to enter the trunnion. The M107A1 the Bolt Lock is part of the accelerator rod assembly and engages the M107A1 bolt through a milled slot in the side of the carrier and pushes against a cutout on the side of the bolt . The Accelerator Rod moves forward upon recoil and the Bolt Lock pushes and holds the bolt forward via a step in the accelerator rod. The bolt lock continues to hold the bolt forward for the duration of the bolt group recoil stroke until the accelerator rod clears the channel in the lower receiver and the Accelerator Rod and Bolt Lock both retract as the bolt re-enters the trunnion.   I have read that the rotating "cam slot" is also different on the M107A1 bolt head but comparing my M82A1 to by buddies M107A1 the cam slot is virtually identical. (this may be another update that Barrett did on later gen M107A1s)  Its probably not really financially practical to purchase an entire new bolt group from Barrett just to get the updated Bolt Lock and some Nickle Boron coated parts. I am also not sure if Barrett will sell you an entire bolt group due to potential headspace concerns. Shooting an older variant M107A1 without the updated barrel reciprocating springs and hydraulic buffer with the QDL installed the recoil is really pretty stout. The barrel hits the impact bumper and trunnion much harder due to the 40lbs barrel recoil springs vs. the 90lbs springs. This imparts more energy into the the bolt group which then comes back at a higher speed into the back of the receiver and the hard plastic polymer buffer and steel sleeve results in the bolt group coming to a much more abrupt stop vs. the hydraulic buffer. Once the high velocity bolt carrier comes at an abrupt stop when bottoming out on the back of thereceiver, the bolt head will want to continue to travel reward putting a lot more stress on the bolt lock assembly. In response to all of this additional force on the Bolt Lock assembly when fired suppressed, it appears Barrett moved the bolt lock to the accelerator rod and beefed up the design to deal with this increased bolt group speed on the older M107A1 variants and prevent damage to the older M82A1 spring loaded lever design. This updated bolt head lock also means you can't remove the accelerator rod from the M107A1 either as the bolt lock won't function anymore. However, once you update the M82A1 with the M107A1 barrel impact bumper, barrel reciprocating springs, recoil spring, and hydraulic buffer the speed of the bolt group even with the QDL actually appears to be very similar to an M82A1 unsuppressed based off how far empty cases are ejected as well as felt recoil. With those spring and buffer parts now better controlling the bolt group velocity, based off my experience I don't really believe the updated bolt group with the Accelerator Rod based bolt lock is really 100% required to mitigate damage to the M82A1 bolt lock design. My personal M82A1 suppressed is much softer shooting than my buddies older gen M107A1 with the QDL installed and his gun is technically "suppressor ready". My guess is the later gen M107A1s with all the spring and buffer updates are probably more similar to my updated M82A1 in felt recoil but I don't know anybody local who has a latest gen M107A1 to compare with. This is also my suspicion why some folks find their suppressed M107A1 recoil harsh and others don't based off the updates their M107A1 has or doesn't have. Without these updates to control bolt velocity and recoil I can understand how a standard M82A1 with a QDL installed the bolt group velocity and recoil would be even worse than an older M107A1 and why you could start to break stuff like the M82A1 spring loaded lever Bolt Lock, damage the charging handle, and damage the receiver where the accelerator arm cams on the lower receiver pocket or the rear of the charging handle slot. This is the setup I personally run on my upgraded M82A1 with the QDL. - M107A1 Barrel Impact bumper - M107A1 Barrel Reciprocating Springs - M107A1 Recoil Spring - M107A1 Hydraulic Buffer with Steel Sleeve. - For additional bolt group buffer margin since I still have the older design lever Bolt Lock with the M82A1, I also added a 1/8" thick ~80 durometer polyethylene rubber buffer in the rear of the receiver so its never a metal to metal contact with the hydraulic buffer or buffer sleeve to the rear of the receiver. I also added a 1/8" thick ~60 durometer rubber buffer between the rear of the bolt group and the front of the hydraulic buffer so its not a metal to metal contact at that interface either. - I also updated the recoil pad to the thicker/softer Ratworx buttpad and the softer Barrett Velcro "cheek pad" vs. the hard plastic pad on the M107A1. My all steel M82A1 also weighs ~5lbs more than the traditional aluminum upper based M107A1, so part of that softer recoil on my gun may also be also due to the M82A1 just having more mass than the M107A1. I have not seen any signs of wear on my accelerator rod area in my receiver or any damage to my Bolt Lock lever. I also run my M82A1 both unsuppressed and suppressed with the accelerator rod installed. Personally I didn't want to sell my M82A1 locally for ~$6K (knowing it had a really high chance of ending up with the cartels in Mexico) and then having to buy a ~$12K M107A1 replacement gun just to run a QDL when I could just update my M82A1 for ~$1K in parts and then add the QDL. As for whether this was all worth it, it was absolutely worth it to me. The 20" barrel M82A1 the muzzle blast was really bad. It would give me a headache after only a mag or two and shooting it prone on the ground would leave the shooter and everything around the gun completely covered in dirt. With the QDL installed the blast is reduced by probably 90% making it much more enjoyable and practical to shoot.   |
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Just trying to ad l Live link . Jp https://youtu.be/hlAW2zvf29c?si=bKrE8cN11pKJThzd |
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