A Data-Driven Approach To Precision Rifles, Optics & Gear
Home / Reviews & Field Tests / Field Tests & Studies / Muzzle Brakes: Recoil Reduction Results Summary
Best Muzzle Brakes

Muzzle Brakes: Recoil Reduction Results Summary

This post provides a comprehensive view of the muzzle brake recoil reduction data gathered on all 4 rifles. You can dive deeper into the recoil data in these posts:

To recap, here is a look at the 4 cartridges and rifles used for the recoil tests:

Rifle Recoil Test CartridgesRifle Recoil Test Rifles
First, let’s look at how the recoil signature of each rifle was affected. The graphic below shows the amount of recoil force over time for each rifle, which was directly measured at the butt of the rifle. Each line represents almost 1000 data points, which were recorded in about 1/100th of a second. That is over 10 times faster than the blink of an eye! The graphic shows recoil signatures for the rifles with a bare muzzle (i.e. rifle without any muzzle device), as well as the recoil signature for the muzzle brake that did the best job at reducing recoil for each of the rifles.

How Muzzle Brakes Affect Recoil

You may be wondering why some of the recoil signatures are smooth and others are more irregular. I believe much of that is correlated to stock design. Those unique quirks in the recoil signatures were consistent for a given rifle, even when using different muzzle brakes. In fact, you can see echoes of the same patterns of peaks and valleys in the bare muzzle and best muzzle brake signatures shown above, within the same rifle. I did test other rifles chambered in 6.5 Creedmoor and 308, and while the % of recoil reduction for the muzzle brakes were very similar within the same cartridge … the recoil signatures seemed to vary based on the stock. Just as a reminder, the 6XC was a Manner’s Carbon Fiber Stock, the 6.5 Creedmoor was a McMillan A5 Stock, the 308 was a standard Savage stock (not their AccuStock, but their cheapest stock), and the 300 Norma Mag was an Accuracy International AX chassis. This isn’t a stock field test, but I thought that was interesting to note … and maybe an idea for a future project! 😉

It’s clear that muzzle brakes significantly reduced the recoil of the each rifle. Not only was the peak of the force reduced, but the total impulse or momentum coming back at the shooter was also reduced (represented by the total “area under the curve”). I explained those two aspects to recoil in more detail in the recoil post, including why some people believe one or the other to be more important. Here is a summary of the underlying numbers behind the recoil signatures shown above.


Test Rifle
Weight (lbs)

Average Impulse (lbf·s) Average Peak Force (lbf)
% Diff Bare
% Diff
6XC 16.2 3.80 2.56 33% 655 455 31%
6.5 Creedmoor 14.1 4.42 2.64 40% 880 476 46%
308 Win 6.2 4.61 3.01 35% 1034 490 53%
300 Norma Mag 15.7 8.62 4.88 43% 1452 739 49%

By using a muzzle brake, we were able to tame the monster 300 Norma Mag so that it felt more like a bare muzzle 308 or 6.5 Creedmoor. We were able to cut the recoil on a featherweight 308 Win to be much less than a hefty 6XC (roughly the same cartridge as a 243 Win). I can confirm that your shoulder feels the difference!

Results & Overall Ratings for Individual Brakes

Now let’s get to the results of the individual muzzle brakes. The heat map below shows the average % reduction for each muzzle brake and rifle tested. The percentage shown is the average of the reduction in overall momentum and the reduction in peak force. The numbers in bold indicate the top performer for each cartridge. That was the Alamo Four Star Cowl Induction Muzzle Brake for all but the 308 Win, where the APA Fat B* did slightly better. Both of the Alamo Four Star and American Precision Arms (APA) muzzle brakes seemed to outpace the others when it came to recoil reduction.

Muzzle Brake Recoil Reduction

Update: The Alamo Four Star muzzle brake design was purchased by Masterpiece Arms, and is now sold as the MPA Cowl Induction Muzzle Brake.

I came up with an overall rating for each brake, which is indicated in the last column above. On my rating system, if a brake were to have an average recoil reduction of 15% or less, it would receive a rating of 0. That seems like the bare minimum into this game. On the upper-end, if a brake reduced recoil by an average of 44% or more, which only the top 2 brakes did, it received a full 10.0 rating.

I devised several methods for ratings, but this seemed the most objective and fair. With this rating system, none of the numbers are based on where a brake ranked relative to the others tested. A muzzle brakes rating is entirely based on its own performance.

Here is another visualization of the overall ratings, including a photo of each brake. This allows you to see which designs are more effective when it comes to recoil reduction, and spot some common characteristics among the top performers.

Muzzle Brake Review

Pros & Cons of Angled Baffles

One thing interesting to note, that isn’t apparent in the photos, is that the top 5 performers all have angled baffles (i.e. the baffles aren’t perpendicular to the bullet path).

Straight Vs Angled Baffles

Here is a breakdown of how much the top muzzle brakes are angled back toward the shooter (0° indicates the baffles are perpendicular to the bullet path). There seems to be a strong correlation between the angle and overall rank.

  1. Alamo Four Star Cowl Induction Brake = 35°
  2. American Precision Arms Fat B* = 30°
  3. American Precision Arms Little B* = 30°
  4. JEC Recoil Reduction Brake = 15°
  5. Holland Radial Quick Discharge Brake = 15°
  6. Center Shot Rifles Blast Tamer = 0°
  7. JP Recoil Eliminator = 0°
  8. Impact Precision Muzzle Brake = 0°
  9. JP Large Compensator = 0°
  10. West Texas Ordnance Muzzle Brake = 0°

I believe there are only 2 outside the top 5 that have angled baffles, the tiny TBAC Compact Brake and the smaller version of the Holland Radial Quick Discharge Muzzle Brake.  The angle definitely isn’t the only thing that plays into recoil performance, but it’s clearly significant.

However, in the section on muzzle devices from Dr. Carlucci’s textbook, Ballistics: Theory and Design of Guns and Ammunition, he reminds us “Best design practice is to divert gases to the sides of the weapon, because rearward diversion could affect an exposed gun crew.” During my tests, a manufacturer sent me a prototype of a muzzle brake with 45° baffles back toward the shooter. It provided outstanding recoil reduction (better than anything shown here), but while testing that brake, a friend helping me with the tests caught some shrapnel in his side. It penetrated 2 shirts and caused a wound deep enough to see flesh. I told the manufacturer I wouldn’t write about it, because I didn’t think it was safe. They were concerned as well, and haven’t release that prototype for sale.

The other downside of angled port designs is increased concussion/blast. All of the muzzle brakes are loud, but diverting gases rearward can increase the pressure shock wave at or near the shooter’s position. Some shooters would rather deal with the extra recoil than the increased concussion from that shock wave. So that is another thing to keep in mind. The sound test should give us insight into the pressure difference at the shooter’s position for each brake, so stay tuned for that.

There are clearly downsides to rearward deflection of gases, but it also has a measurable influence on recoil reduction. I don’t want to present this as “right or wrong.” It’s up to each shooter to strike the right balance for their application. I’m just trying to give a balanced and responsible presentation of all the facts to help you make an informed decision.

Next Up

In the next post, I’ll cover the results related to how well each muzzle brake helps you stay on target. David Tubb, one of the most accomplished rifle shooters in history, helped me develop this part of the field test. David believes this is the most important aspect of muzzle brake, and much more important than recoil reduction. So stay tuned!

Want to be the first to know when the next set of results is posted? Sign-up to receive new posts via email.

Other Post in this Series

This is just one of a whole series of posts related to this muzzle brake field test. Here are links to the others:

  1. Field Test Overview & Line-Up: Overview of how the tests, what brakes were included, and which were caliber-specific.
  2. Recoil Reduction Results: Let’s get right to the meat!
    1. Recoil Primer, Test Equipment & Rifles: Explains how I tested, and what equipment and rifles were used.
    2. Results for 6XC and 6.5 Creedmoor: Recoil results for the mid-sized 6mm and 6.5mm rifles.
    3. Results for 308 Win and 300 Norma Mag: Recoil results for the mid-sized 30 caliber and large magnum 300 rifles.
    4. Summary: Overview of recoil results from all rifles, and overall ratings of each muzzle brake.
  3. Ability to Stay on Target: Lasers and high-speed cameras were used to objectively quantify how well each muzzle brake helps you stay on target through a shot.
  4. Sound Test: A high-end sound meter was used to measure how loud each brake was to the side of the rifle and at the shooter’s position behind the rifle.
  5. Muzzle Blast & Ground Signature: High-speed videos were shot of each brake to show the direction of the muzzle blast, and the impact that could have on the shooter.
  6. Overall Summary: Putting all the results together in a summary that is easy to take in, and do side-by-side comparison, allowing you to draw your own conclusions on what muzzle brake is best for your situation.

About Cal

Cal Zant is the shooter/author behind PrecisionRifleBlog.com. Cal is a life-long learner, and loves to help others get into this sport he's so passionate about. Cal has an engineering background, unique data-driven approach, and the ability to present technical information in an unbiased and straight-forward fashion. For more info, check out PrecisionRifleBlog.com/About.

Check Also

6.5 Creedmoor factory Ammo comparison

6.5 Creedmoor Ammo Test Part 5: Live-Fire Group Sizes & Precision

Welcome to Part 5 of the results from my massive 6.5 Creedmoor ammo field test! ...


  1. It sure seems from your phenomenal graphics [ loved the alternating value, color coded and color shading effectiveness at conveying magnitude ] that the brakes with more and larger baffles were most effective.
    I wonder if anyone is producing a brake with the baffles angled slightly downrange away from the shooters ears ? Or the first baffles could to pointed downrange for noise attenuation then subsequent baffles directed back for peak efficiency…thus they would cancel out much of the blast reaching the shooter.?.
    Your test protocol seems to be a tool licensable to this small industry and also to the internal baffle structure of suppressors.

    • CR, those are all good points. Honestly, I’m not sure. Based on some of my other tests and computer simulations I’ve heard about, the 1st baffle is doing the majority of the work. So I’m not sure what the impact would be. I’ve talked to one engineer who does supersonic flow modeling on brake designs, and that sounds like the best way to “try out” design ideas like that. But, out of all the brake manufacturers I’ve talked to (more than what’s represented here), there was only one doing that kind of computational modeling to aid in design. I have a few ideas myself after handling all these brakes. I might just float them out there in a post after this series and maybe someone would be ambitious enough to try these kinds of things out. Wish I had a CNC machine! As always, CR, thanks for the thought-provoking feedback.


  2. Thanks for the effort on this very detailed study. Have you ran across the J E Custom muzzle brake (not to be confused with JEC Custom). Apparently they ‘tune’ the brake to your load.

    • I haven’t, but it sounds interesting. I’m not sure what tuning it to a load would mean. But, just because I don’t understand it doesn’t mean it won’t work! Gravity works regardless of whether someone understands how it works or not! 😉 It sounds like an interesting idea. Some of these, like the Tubb brake, can be used to tune the barrel harmonics by screwing it in and out and essentially adjusting the weight distribution of the barrel, which changes the vibrations. That can be thought of as tuning to a load, because the harmonics would be specific to a load. I wonder if that’s what they’re talking about. I’ll have to check it out! Thanks for mentioning it.


      • Ah – Thanks I was ambiguous. By tuning I meant they would tune the muzzle brake for maximum recoil reduction – given the load (muzzle exit pressure I assume). Not sure just how it’s accomplished but he has a series of YouTube videos demonstrating the before/after. Here’s a link to one of their tests. https://www.youtube.com/watch?v=327beJrl5vU

        So this really stumps me as I would think one would need some sort of Computation Fluid Dynamics software to get in right in the modelling stage, but I support lots of testing and empirical data can get you close.

      • Interesting, but I still don’t get it. Personally, I’d be afraid it’s snake oil … but it certainly might not be. It’s plausible that you’d be able to “tune a muzzle brake design” to be optimal for a certain caliber, and amount of gas and pressure, but micro-tuning for a specific load seems like a marketing ploy. Computational fluid dynamics software can help, but modeling supersonic flow in 3 dimensions is VERY processor intensive. That’s why some academic studies out there are only able to model in 2 dimensions (like this study). Based on the quality of those YouTube videos, it seems unlikely that those guys are more technologically advanced than the academic community. I’m not an academic guy, so I’m not trying to take a low-brow view of them, but I’m just suggesting you approach with caution.


  3. Just to state again, great series!

    “a prototype of a muzzle brake with 45° baffles back toward the shooter .. a friend …caught some shrapnel in his side. It penetrated 2 shirts and caused a wound deep enough to see flesh.”

    Interesting finding. Obviously there should be no ‘shrapnel’, or any other solid matter of note, leaving from any vector save the muzzle. Was the shrapnel from some misalignment, or from some remaining milling debris or flashing, (it -was- a prototype) , .. or did the shrapnel seem to be a function of destabilization in designs using such a radical degree of cutback?

    • Yeah, it was quite the surprise. At first I thought he was joking, and then I thought we were going to the hospital! In the end, I had a first aid kit with everything we needed to flush it, clean it, and bandage it up. We’re not exactly sure what happened, but it was some of the first shots out of that Savage rifle. So my guess is it may have been from a burr on the chamber or rifling. But it could’ve been off the brake too. It didn’t appear to be a baffle strike. There was no apparent damage on the brake.

      Ultimately, it probably just isn’t good to through combustion exhaust back at that angle. At a match back in March, I was sighting in with a few other guys and reached up to make sure my suppressor was on tight. The guy beside me shot while I was stretching forward. He had an angled brake and I got peppered in the face with some debris. I bet it was unburned powder granules. Luckily I was wearing eye protection, and that’s a good reminder of why that’s so important. It wasn’t a big deal, but if you caught some of that in your eye it might be.

      Ultimately, it’s a violent explosion every time you fire a round. It’s controlled, but there could be more than a bullet and gas that comes out of the barrel. Think about how much copper comes off the jackets, and how much carbon you have to clean out of the barrel. It doesn’t seem to be a stretch to think some of those kinds of particles may be blowing out the end of the barrel on every shot. Those kinds of things travel with the gas, so when you redirect the gas rearward, you may also be redirecting those particles as well. This is all theory, and I don’t have any hard data or slow-mo video to prove it … but it seems plausible.

      Great questions! I wish I had the answers. At this point, you know everything that I do about what happened. All I know is that you won’t see me using a 45 degree muzzle brake!


  4. Cal,

    You brought up a great point regarding the up-sides and down-sides of the rearward facing baffles and their increased concussion.

    I was seriously considering purchasing the APA little “B” for a rifle I am having built right now, but decided against it because many of the reviews I read said that while it’s an effective device for cutting down recoil, it also has a tendency to throw up a lot of dust which quickly inhibits the shooter’s visibility downrange.

    I hope one of the metrics you address will be the varying dust signatures of each muzzle break??? I do believe this to be an important consideration, and I’d be curious to see how each muzzle break ranks in this department.

    Thanks again for all your fantastic work!!! I thoroughly enjoy your research and efforts!


    Aaron Z

    • Hey, Aaron. That’s a great point, but that hasn’t been my experience with the APA muzzle brakes. I actually ran the APA Little B* on my personal rifle in two matches over the past month, and I never even noticed dusting or a ground signature that was distracting or impeded visibility. It sounds like others had a different experience. I do plan to post some stuff related to muzzle blast. You can see where that will fall if you look at the upcoming posts in the Other Posts In This Series section in the post.


  5. Great writeup as always !
    It seems unbelievable that the 6 Lbs 308 rifle recoils as much as the 14 lbs 6.5 creedmore, can someone explain that to me ?

    • Thanks, Julian. And great question! Next question, please. 😉 I can’t say that I can explain this fully, but I’ll point out a few things. First, if my goal of this series was to compare recoil of different rifles and cartridges, I’d have presented the data differently. I may have presented it in terms of energy or work, which you can derive from the force over time data. Both should be proportional to the impulse (area under the force vs time curve), but would likely be the bigger difference that you might be expecting. I didn’t do that because I wanted to stay closer to the raw data that was recorded, and since it’d be proportional to the data I presented … the rating of muzzle brake performance should be the same either way. I was hesitant to show the rifle comparison, but thought it was a cool visualization to help people wrap their heads around what was happening to the force at the butt of the rifle when you apply a brake. Sorry if that was more confusing than helpful.

      Secondly, there is a difference. It might look slight on that graph, but that is mostly because the 300 Norma makes the scale stretch way out. Here is another look at that same data:

      6.5 Creedmoor vs 308 Win

      The impulse (area under the curve) is 4.4 lbf•s on the 6.5 Creedmoor, and 4.6 on the 308. That might not sound like a lot, but it is noticeable. The biggest difference is in how that force is applied. The 308 has a much higher peak, 1034 lbs compared to 880 lbs. That is almost 20% more than the 6.5 Creedmoor. Those still might not be as high as you’d expect, but they are in the same ballpark of what the JBM recoil calculator predicts for the Free Recoil Impulse. While this is far from a free recoil scenario (free recoil means the rifle can move freely with nothing supporting it from the rear). That isn’t the same as when you’re firing a rifle (your shoulder is supporting the rifle from the rear), and it isn’t the same as what this test was (rigid steel base supporting rifle from rear). Those scenarios are really difficult to predict/calculate, so most recoil calculations are based on a much simpler scenario that ignores collisions, and that simpler scenario is called free recoil. But, we can still learn stuff from recoil numbers. If you run the data for the lightweight 308 vs the 14 lb 6.5 Creedmoor, JBM says the free recoil impulse of the 6.5 Creedmoor would be 2.6 lbf•s, and the 308 would be 2.8 lbf•s. So that shows there just isn’t a big difference in overall impulse between the two rifles.

      And finally, what will be really different between the two is the acceleration of the rifles. My charts show force over time, but force is simply mass multiplied by acceleration. So for the force to be in the same ballpark, if the weight is much lower, then the acceleration has to be much higher. You can actually calculate the acceleration of the two fairly simply, if you’re interested.

      The thing you have to keep in mind is that impulse (area under the curve) is just the change in momentum. The momentum is always directly proportional to the momentum of the bullet plus the expanding gases. Momentum is just mass times velocity. The powder charge is similar between the 6.5 Creedmoor and 308 Win, so the momentum of the gases is virtually the same. The only difference is the bullet. The 6.5 Creedmoor sent a 140gr bullet 2810 fps. The 308 sent a 168gr bullet 2650 fps. Those are different, but the calculated momentum isn’t drastically different. The bullet weight went down on the 6.5 Creedmoor, but the velocity went up … so the net effect on momentum isn’t enormous.

      Hope this helps. Definitely a great question! This is about all I could think of to speak to that. All I can say for sure is that is what was recorded, so that’s what I’m presenting. Maybe someone else will chime in and help us understand it.


  6. Sir,
    I look forward to your articles, very informative, very interesting as I shoot long range, so, I can’t wait to the next write up. These have been very helpful in my long range shooting on the products that I use. Your a very brilliant young man, keep up the great work! Thanks again for your work!
    Jerry Hunt

    • Thanks for the kind words, Jerry. Glad you find the approach helpful. Just trying to present the data to help fellow long-range shooters make more informed decisions.


  7. My basic question still remains, how much does a particular brake change the accuracy?
    My guess is that it is very load dependent just like each barrel needs a load made for it.
    But given another tuned load to barrel/brake system, can you get back to the same accuracy as bare muzzle for a give brake? My hypothesis is some yes, some no.

    • Jesse, I’m afraid I still don’t have an answer for you. I didn’t test accuracy with the brakes, because I couldn’t think of an objective way to do that. I would rather not publish results on something, rather than publish results that could be misleading. For me to be confident in accuracy results, I’d want to use a rail gun … and I don’t have one (yet). I also thought about getting 3 shooters to shoot a few 10 shot groups with each brake, and average all the results … but I think you’d be “in the noise.” I doubt it would offer enough value to justify the cost of the match-grade ammo it would take to conduct the test.

      Since I couldn’t come up with a really objective way to quantify that … I didn’t do any tests on it. Having said that, I’d be surprised if any of these brakes affected accuracy in any measurable way. I don’t know that (wish I did) … but that is my hunch. Perhaps if you’re a benchrest shooter you might notice something … but for us practical/tactical guys … it’s likely in the noise, and you wouldn’t miss a target because of it.

      It’s actually plausible that they could improve accuracy. I plan to speak more towards this in a later post, but I’ll give a short explanation here. I used to not believe a brake or suppressor could make a rifle more accurate, but it actually is plausible. This is because a muzzle brake is decreasing the amount of gases that the bullet has to fight through in the early part of it’s flight, because it sends a portion of that gas to the sides, instead of it all being forced to exit along the bullet path. I don’t want to nerd out on you, but there is an area of ballistics called transitional ballistics, and it is a short period between internal and external ballistics, between the time the bullet comes out of the barrel until it stabilizes in flight. It is actually a fairly violent period for a bullet. Here is a cool photo of that period from Herra Kuulapaa (shared with permission), and he has a lot more photos like this on his website.

      308 Photos from Herra Kuulapaa

      Then here is a photo from Herra Kuulapaa with a muzzle brake attached:

      Muzzle Brake Slow Motion Photos

      If that transitional ballistics is less turbulent, that may mean the affect on the bullet is more consistent and there would be less shot-to-shot variation. At least it’s plausible that could happen.

      But, like I mentioned before … I bet we’re in the noise. If you’re not a benchrest guy, you likely wouldn’t notice any impact these muzzle brakes would have on accuracy. That’s just my guess.

      I realize that probably isn’t what you want to hear, but unless you are buying me a rail gun … I’m not testing accuracy.


  8. Great info: Did you look at the bore diameter of the brake compared to the bullet diameter ? It would seem that the proper fit would have an effect on the efficiency of the brake. I have a clamshell brake for a .50 and the bore starts out larger than .500 and steps down closer to .500 at each baffle. Thanks for the hard work. Eddie

    • Great question, Eddie. I actually tested that. I was wondering how much it mattered if you were using a generic 30 caliber brake on a 6mm or 6.5mm, compared to if you were to using a caliber-specific brake. So that is roughly the same thing you’re asking … how much does the size of the hole matter. I mentioned that test in the post about 6mm and 6.5mm recoil results, here is the excerpt on that topic:

      I ran tests to see how much it mattered if a muzzle brake was caliber-specific, and those results were also surprising. I tested the effectiveness of having a caliber-specific brake on 4 very different muzzle brake designs that I had in all calibers: the APA Little B*, Holland 1.25” Radial QD Brake, Impact Precision Brake, and West Texas Ordnance Brake. I only found an improvement of 1-3% if a brake was 6mm rather than 30 caliber (7.62mm).

      To be clear, I tried the 6mm, 6.5mm, and 30 caliber brakes all on the 6XC, and in all 4 muzzle brake designs, there was only a difference of 1-3% in recoil reduction in terms of both overall momentum and peak force. That surprised me. I expected the caliber size of the bullet hole in the brake to make more of a difference. But, that’s why I actually run the tests and don’t just talk about this stuff!

      So like I said in that post, I was surprised how little it mattered. There was actually a sharp engineer that chimed in in the comments, and tried to explain why this was the case. It’s pretty technical, but it has to do with choked flow of fluids. He even gives some of the math behind it. If you’re interested, here is a link directly to that comment:



  9. Cal,

    As usual, a very useful review – keep up the great work! I am pretty amazed the range of difference and none of us would be the wiser without someone like you doing the work.

    The benefits of a break is clear but unfortunately using one in a match (non-PRS) sometimes brings on the ire of some of the other shooters, especially F-class shooters who cannot use a break and so is not used to them. I personally are always double plugged (custom silicone plugs + electronic ear muffs) and so am not so affected. However, I would have been quite interested in a parallel noise level study of the brakes you tested to see if there was a sweet spot where you get a generous reduction in recoil without a proportional increase in sound level or for that matter whether a reduction in recoil always cause a parallel increase in sound level. I would be willing to bet that the latter is not true due to the different designs of the brakes.

    • Thanks! I know muzzle brakes are taboo or even banned in some competitions … that is tough, but I understand it. I also go double-plugged most of the time, because hearing damage is cumulative and permanent. I did record the noise level of each brake with a really high-end sound meter. I recorded it at the side of the rifle (according to mil-spec standards), and then also at the shooter’s position behind the rifle. I’m going to post those results soon, and I will point out the correlation with recoil in that post. I’ll also be sure to point out any brakes that reduce recoil unusually well compared to how loud they are. Stay tuned!


  10. Im still curious why 308 is the only one to have such a discrepancy between the change in momentum and the change in peak force. the other three cartridges were about 3-6% while 308 was like 17%.

    AT first I thought it could be that more of the momentum is in the bullet (which is momentum the brake does not affect). So if your brake diverted 50% of the gasses, then a cartridge with 3 lbf-s gas and 1 lbf-s bullet would have 2.5 lbf-s after the brake, while one with 2lbf-s for gas and bullet would have 2.0 lbf-s after the brake even though they had the same starting impulse.

    But I did the math (I couldn’t find a velocity for the 308 you fired so I assumed 2700) and found there to be no correlation between the % of the momentum that came from the bullet and the difference between % reduction momentum and % reduction of peak force.

    Table from Adith

    The 308 does have the highest % of momentum from the bullet at 44%, but the 6XC is not far at 37% despite having the lowest difference between reduction of peak force and momentum.

    I’m out of ideas, any other explanation for 308 being weird?

    • Adith, you got me. Someone else might chime in with an explanation though. I just try to post the data exactly as it was recorded. What I’ve learned is that even if I can’t explain it, there is usually a reason. A great example is the surprising data showing that caliber-specific brakes were only 1-3% more effective than a generic 30 caliber equivalent. While I couldn’t explain the science behind it, I just knew that’s what the data showed. And after I posted the data some smart guy came along and explained choked flow and incompressible fluids, and it totally made sense. He even gave the math behind it. 😉 (Just kidding here … that smart guy was actually Adith. Very sharp guy indeed.)

      I did run that lot of Federal Premium 308 ammo over my new LabRadar chronograph this past weekend (which is stupid awesome), and it was running an average of 2658 fps out of a 20″ barrel. I recorded 44 rounds, and it had an SD of 10.4 fps. That was impressive! I didn’t expect it to be that good. But that’s probably why that ammo is so legendary. I realize that doesn’t help your concern, but it is impressive. I know there are a ton of sharp engineers that read this, so maybe someone else will chime in.


  11. I’m only a pilot but this seems obvious …its the light weight of the .308. I could scroll back up the post and be exact but hell, the light weight hunting model .308 without optics weighed just over half of the heavy target rifles.

  12. Cal, did you consider using a Terminator brake from Terminator Muzzle brakes in New Zealand ? I see you feature Greg Couper’s testing sled as one of your images, so no doubt you are aware of his products.

    I have 5 of the T3 version of the brake on the calibres 204Ruger, 243Win, 260Rem, 308Win and 300WinMag and they are amazingly effective. From what I can see, the APA and Alamo Four Star brakes appear to be a similar design to the Terminator.

    I have seen the APA FB tested on Greg’s test sled and the T3 brake is even more effective than that. The ports look to be swept back approximately 45degrees, so they definitely send some shockwaves to the person beside you.

    For those not familiar with the Terminator brakes, Greg has a great set of You Tube videos where he demonstrates his brakes’ effectiveness on various calibres and against other brakes, using a sled for consistency. It is quite eye opening to see how effective some brake designs are on heavy recoiling calibres, especially when he does a demonstration with no brake.

    This is a great test BTW, Cal.

    The point about muzzle brakes and safety concerns is definitely valid. There is always the possibility of a jacket separation when pushing projectiles to very high velocities and also any debris in the barrel can become a projectile itself. The safest brakes in these instances are those with ports that are angled forwards. One of our local benchrest ranges has put up removable barriers between benches for non-completion use. That way, when the guy with the new 338LM and the enormous muzzle brake starts shooting next to you without the obligatory warning, you don’t end up with all your paperwork blown away and a raging headache.


    • Yes sir, I talked to Greg early on this process, and he was really helpful. His videos are well done, and show the advantage a muzzle brake offers in a very clear and compelling way. One of the tips Greg gave me was if you want to really push a muzzle brake, test it on a big magnum pushing heavy bullets. That is when I decided to go 300 Norma with the heavy 230gr Berger bullets. The Terminator design does look really similar to the APA, but I’m hesitant with 45 degree baffles. If that it what it has, it’s probably more effective … but also more dangerous. I’m not sure I’ll ever be comfortable around a 45 degree brake personally, after seeing what happened to my buddy. That could’ve been much worse, so I’d just prefer to go a little safer … Even if it means I endure slightly more recoil.

      I’ve never seen a range with those barriers you described, but it sounds like a great idea. The concussion from those big magnums can devastating. Nobody likes being next to “that guy” … of course sometimes I am that guy! 😉

      Thanks for the kind words. Glad you found it helpful.


      • haha youre too kind!

        I guess we need more data to really find out!

      • Greg, the guy who makes the Terminator muzzle brake, emailed me and said the Terminator has 34 degree baffles … not 45 degree baffles. That makes me feel a lot more comfortable.

        That also could explain the difference in performance you mentioned over the APA design, which features 30 degree baffles. 4 degrees might sound tiny, but its plausible that it could result in a measurable difference.

        Just wanted to pass on the info on the angle of the Terminator brake.


      • Apologies to Greg. I hadn’t measured it when I commented. Pulling out the set square shows that yes, it’s not 45degrees and a bit more than 30degrees, so 34degrees makes sense.

        Cal, will you be testing this brake ? There are a few to choose from. I’d really like to see the numbers on how the T3 stacks up against this lot. Or the T2. Or the T4. Etc.

        Think of them as the Schmidt & Bender of muzzle brakes.

      • Wow, Schmidt and Bender of muzzle brakes. That’s a bold statement. I didn’t include the Terminator brake in this test, and it’s already in the books. But, I may consider testing it in the future. Lots of people have asked me about it. I wish I had the numbers on it. Having handled a lot of muzzle brakes, I’d bet it’d be a top performer.


      • I run multiple Terminator brakes and I’ve never seen an issue with excessive dust or debris. I have run other brakes and the Terminator is by far the best brake. It sounds to me like you guys neglected to check your bore for obstructions……
        You could’ve had a piece of cleaning was stuck in there…..
        Greg’s brakes have beat out the APA brakes in testing…..
        A few people I know run his brakes, including myself and we’ve found his brakes more pleasant to shoot than other designs, even the designs with no sweep back.
        It would seem to me that the US brake manufacturers didn’t want the competition;)

      • No sir, we uncovered that we were likely hit by a piece of carbon that had built-up on the brake (like it does on all brakes), and eventually blew off (like it will eventually do on all brakes). The problem was the steep 45 angle back toward the shooter meant it actually hit and injured someone instead of going off to the side unnoticed.

        I’m not saying Greg’s brakes aren’t awesome. They appear to be, and I’m glad you’re happy with them. After my first-hand experience, I’m just not comfortable with any brake that angles back to the shooter at 45 degrees or more … regardless of the performance it offers. I believe it’s a serious safety issue, but you don’t have to believe that. To each his own. I’m obviously not trying to sell anything here, so you can take it or leave it.


  13. Cal I didn’t read all the comments but the debris which likely impelled your friend was carbon build up in the brake which came loose and was driven rearward. I’ve seen this more than once and know guys who have been shooting on the line and stuck with carbon chunks that drew blood. It’s one of the disadvantages of angled ports. Please guys, where eye protection when shooting near brakes.

    • Thanks for chiming in, Jim. That was the first time I’d experienced something like that, and I’m hoping to not experience it again. I guess you spend enough time behind a rifle and you see things like that. That does make sense. I noticed carbon build-up on the brakes, and of course that stuff will break loose eventually … and be carried at high speeds in whatever direction the gas is going. Yikes.

      Clearly something to keep in mind. I couldn’t just mention the recoil stuff without also making sure readers were aware of the potential safety hazard of angled baffles. I appreciate you sharing your experience!


    • Very good analysis Jim. I will sure keep that one in the back of my mind when around people with brakes…as is often the case in Africa shooting magnums.

  14. Great work as usual Cal and thank you for your time and effort. My question is did you add a suppressor in with these test like you did the muzzle movement test. I was a little disappointed to hear that the suppressor did very little to combat muzzle movement and now curious about felt recoil compared to a brake. Again, thank you.

    • Yes sir. I did post how a suppressor compared for the 6XC, 308 and 300 Norma, but didn’t combine that stuff in the summary. When you drill into those individual results, you can see how the suppressor compared. It finished about the same as the ability to stay on target … usually towards the tail end of the pack. You can view those results here:


  15. Greg from Terminator Products recently sent me a cool video of a test he did with a few of these brakes. It’s essentially using clever a recoil sled setup, which is an intuitive way to quantify total momentum or impulse (which is simply the change in momentum). This approach films really well, and it’s simplicity is very engaging.

    Watch YouTube Video: Terminator Brakes VS The APA Fat B*tard & Alamo 4 Star

    Greg mentioned that he ordered a couple JEC brakes so he could include one of those in the comparison, but hasn’t received any of them yet. A few people have mentioned that JEC seemed to be slow in processing orders. I’d imagine the demand after this series of posts might have overwhelmed them for the moment. My bad! 😉 Hopefully those guys will be able to catch up soon.

    Just wanted to share this, because I thought it was helpful. It also shows a pretty simple and affordable way to compare the change in recoil momentum of various brakes.


  16. In the context of recoil reduction, one bit of data I wish were available for comparison is brake-mounted suppressors and how they would perform in comparison to bare muzzle brakes and direct-thread mounted suppressors. Would the recoil reduction be somewhere in the middle? Does the mounting of the suppressor over the brake negate the advantage in recoil reduction that an open brake would have? Does a brake-mounted suppressor have less recoil than a thread-mounted suppressor?

    I’m considering buying a Dead Air Sandman-S as my next suppressor, and they have an interesting brake design. Just curious how effective this setup might be.

    • Funny you should ask, Kevin! I actually tested both brake-mounted suppressors and direct-thread suppressors. I just didn’t post any of that data (yet). They are virtually identical. Once you screw on the suppressor, the brake becomes integral to the suppressor. So I hope that helps put your questions to bed. I actually didn’t think anyone else on earth would be interested in that! I figured I was the only OCD guy who thought about stuff like that! I was just curious and had all the equipment setup, so I measured it. Good to know someone else could benefit from it!