Asymmetric Muzzle Brake Design

[Albedo]

TL;DR: How do you take into consideration ports on the top of the brake and baffles not on the same plane as the horizontal baffles?



I got around to reading a book a bought a while ago called "Armament Engineering, a computer aided approach" by H Peter. I found the chapter on muzzle brakes really fascinating, however they neglected to cover asymmetric muzzle brake design. On small arms, asymmetrical brakes are the most common, since those ports on the top help to reduce muzzle climb. I have tried looking around for any documents on this subject and found the "Engineering Design Handbook, Gun Series, Muzzle Brakes" by the US Army Material Command and they do mention about asymmetrical muzzle brakes, but I am having trouble understanding what is going on. Their terminology isn't identical to the armament engineering book and they don't break down the equations and seem to have overly complicated ones. Also the asymmetric muzzle brake they describe is really strange, instead of it being a common brake where it has large side ports and a small port on top, it is a funky brake the has the sides hooking up at a specified angle. So I don't think that document will be of much help.



I also have some questions about the calculations and considerations to muzzle brakes. Lets use the one in the image below as a common example one.

Lets say we want to calculate the downward force from having the top right port. Is that considered a separate port? Or do we take that area and combine it with port series 1? Where exactly does it fall into the equations, because port series 2 (the middle side ports) takes values computed from series 1 to yield its' results and since that top port is also redirecting gases, that should effect series 2. Then what about the next vertical port, would it follow the equations relative to series 2 ports and on? But say we used the equations listed in the armament engineering book, we can only compute thrust on the baffle, while what we need is the thrust from the gas flow exiting the port. I am tempted to think they are equal, but the force on the baffle is a force towards the user (i.e. recoil mitigating) while the thrust force from the vertical port is, well vertically downward.

Attached below are the important pages from the armament engineering book so you can see what the equations I am dealing with are. Sorry for the reduced image quality, but the server refuses to upload the images without them being reduced by over 75%...



There are two other images but the forum is glitching saying I can only attach 6 files...when I have only 4, I will add them into a comment if possible.

Any help you can offer in figuring out the hand calculations of these is much appreciated!

 

[Albedo]

These are the two other pictures mentioned in the OG.

 

[Dusty Stevens]

Id be willing to bet every muzzle brake on the market was a test trial that worked well. Anything short of a tank can use one of the 3-4 current designs and sell all they make

 

[Albedo]

Id be willing to bet every muzzle brake on the market was a test trial that worked well. Anything short of a tank can use one of the 3-4 current designs and sell all they make

A lot of brakes to my knowledge were made via rudimentary trial and error, which is fine but is not optimized. CFD also helps a lot and others have used that to do the analysis of the fluid flow and recoil mitigation, however I want to prove mine both hand calculations and computer simulations (i.e. engineering with only computer simulations can be detremental as the outcome is not always as shown in the simulation for various reasons).

 

[Dusty Stevens]

Im sure if you come up with a real good design itll sell like hotcakes

 

[3Sigma]

CFD for unsteady, transient supersonic flow with reacting gases is NOT trivial nor simple. You can spend a lot of time on it, even assuming you have the software, tools, and knowledge.

An emperical approach is much faster. You only need 80% of optimal to be effective.

 

[Dusty Stevens]

CFD for unsteady, transient supersonic flow with reacting gases is NOT trivial nor simple. You can spend a lot of time on it, even assuming you have the software, tools, and knowledge.

An emperical approach is much faster. You only need 80% of optimal to be effective.

Your username gives me nightmares of jack welch making all of us minions do the 6 sigma thing. Sorry off topic

 

[CharlieNC]

Good luck on your quest. It seems to me that much of our shooting technology is based primarily on trial and error, instead of a strong engineering approach which could lead to more in depth understanding and consequently optimization.

 

[gunsandgunsmithing]

You might enjoy this. Good article.

Gunpowder's Contribution to Recoil

Some shooters may not realize how gunpowder affects the amount of recoil they feel when they fire their favorite guns. Here's the lowdown.

www.shootingtimes.com

 

[ballisticxlr]

This is not my area of specific expertise but I do have some education in the matter having designed a number of things that could generally be called manifolds.

That it's possible to represent a frame of a continuous event is fine but people ignore that doing so is a bit like discerning the story line of a movie from a single frame. It's destined to be severely inaccurate. Things like Brownian Motion get involved where there's fluid flow through a manifold of any shape. Add in temperature and pressure gradients that are extreme and it's beyond what a human could really do on paper in any useful way. You can use fluid dynamics modeling software to simulate things for you but when you do you have to parameterize a ton of things. As soon as you parameterize you've done little but made a simulation that isn't likely reflective of reality outside of a highly specific configuration.

If someone wanted to make an insanely effective brake which was also more pleasant than others to be around, they'd look very closely at Pelton type turbines and apply the high pressure + low volume -> low pressure + high volume energy capturing face design. I've done some not insubstantial work on this very front but so far every brake maker I've approached has wussed out when they see how intricate the machining is. It's not just something you can do without a boring bar and there are a number of compound curves. If anyone wants to talk about this, the IP is yours for free if you'll build it and provide me with 2 of them.

Intake and exhaust manifolds on engines and muzzle brakes share a design goal: To move gasses from a-b with the least turbulence possible and then to deliver them to their destination with a great deal of turbulence. So the adages of "bigger holes aren't always better", "don't lower the floor, raise the roof" and "avoid sharp turns" still apply.

People also spend entirely too much time thinking of crafty ways to make their ports cool looking instead of paying attention to how big the surface area of each baffle set is and how far that baffle set is from the muzzle which are very much more important to function.

 

[3Sigma]

Your username gives me nightmares of jack welch making all of us minions do the 6 sigma thing. Sorry off topic

Ha! I feel ya. I was working at GEAE when he handed the company off to Immelt, and you couldn't sweep the floors without a greenbelt. Made my young engineering mind hurt considering how 6 sigma applied to HR.

The name is actually cause I am buried in statistics in my day job (development engineer), and consider expected performance as +/- 3 std. deviations. I had to come up with something, and that was it.

 

[3Sigma]

This is not my area of specific expertise but I do have some education in the matter having designed a number of things that could generally be called manifolds.

That it's possible to represent a frame of a continuous event is fine but people ignore that doing so is a bit like discerning the story line of a movie from a single frame. It's destined to be severely inaccurate. Things like Brownian Motion get involved where there's fluid flow through a manifold of any shape. Add in temperature and pressure gradients that are extreme and it's beyond what a human could really do on paper in any useful way. You can use fluid dynamics modeling software to simulate things for you but when you do you have to parameterize a ton of things. As soon as you parameterize you've done little but made a simulation that isn't likely reflective of reality outside of a highly specific configuration.

If someone wanted to make an insanely effective brake which was also more pleasant than others to be around, they'd look very closely at Pelton type turbines and apply the high pressure + low volume -> low pressure + high volume energy capturing face design. I've done some not insubstantial work on this very front but so far every brake maker I've approached has wussed out when they see how intricate the machining is. It's not just something you can do without a boring bar and there are a number of compound curves. If anyone wants to talk about this, the IP is yours for free if you'll build it and provide me with 2 of them.

Intake and exhaust manifolds on engines and muzzle brakes share a design goal: To move gasses from a-b with the least turbulence possible and then to deliver them to their destination with a great deal of turbulence. So the adages of "bigger holes aren't always better", "don't lower the floor, raise the roof" and "avoid sharp turns" still apply.

People also spend entirely too much time thinking of crafty ways to make their ports cool looking instead of paying attention to how big the surface area of each baffle set is and how far that baffle set is from the muzzle which are very much more important to function.

Keep up on 3D additive manufacturing. It still has a ways to go for cost effective parts, but you can make some crazy geometries not otherwise possible.

 

[ballisticxlr]

Keep up on 3D additive manufacturing. It still has a ways to go for cost effective parts, but you can make some crazy geometries not otherwise possible.

I'm quite up to date on it. It's the only lingering hope for a number of products that I'd conceptualized while running the question of "what does modern machining technology prevent you from doing?" but I also don't think that it's going to be cost effective for mass production for a good while yet and there's going to be a lot of stupid secretary type grief (you know, where the secretary writes down everything the boss says including the part where he says, "don't write this bit down") to put up with before it is.