Deflecting the gases 90 degrees does take the powders mass and velocity out of the recoil equation so it does reduce the recoil. It is not as effective as directing that mass backwards but it does reduce recoil. What I found surprising in the pictures was the difference in the jet coming out the muzzle. Some showed a very strong jet of forward gas while others showed just a wisp of gas. I would think that keeping more gas from exiting the muzzle would make the brake much more effective.
Physics of muzzle brake recoil reduction
- Thread starter carlsbad
- Start date
carlsbad
Lions don't lose sleep over the opinions of sheep.
Yes but. There was some acceleration of the rifle by stopping the gases (I called that A1 in post 19). Then if you send them out sideways, you create nothing with respect to recoil.
So yes, sending them out sideways in a balanced manner does not impart any net force on the muzzle brake/rifle.
I separated the muzzle braking process into stopping the gases (which all muzzle brakes do) and then redirecting them (this is where muzzle brakes differ).
Hope that helps.
--Jerry
So yes, sending them out sideways in a balanced manner does not impart any net force on the muzzle brake/rifle.
I separated the muzzle braking process into stopping the gases (which all muzzle brakes do) and then redirecting them (this is where muzzle brakes differ).
Hope that helps.
--Jerry
carlsbad
Lions don't lose sleep over the opinions of sheep.
Sheepdog,
Yes. In retrospect I didn't make it clear from the beginning that I was talking forces from the gases jetting out.
All muzzle brakes stop a quantity of gases that were moving forward and this provides some (a lot) recoil reduction. Where you send them then can add more recoil reduction or not.
Jerry
dcali
Bullet Maker
That's because it's not gas - it's powder being blown through by an air compressor. It's really just a demo of what sort-of happens, not anything you can take seriously.
Air or pressure can only be reshaped by 11 degrees or less without tumbling . So the angle back of a break is not as important as the size of the relief. A larger break will have less recoil then a small one . Because of the surface area that is pushing back . This answer should be fun Larry
Larry,
turbine blades deflect the flow of gases a lot more than eleven degrees and there is very little "tumbling" or drag there.
it's all done with the shape of the air foils doing the work and the pressure at which it is performed.
Granted most brakes are not designed like air foils but i know there is at least one that is.
turbine blades deflect the flow of gases a lot more than eleven degrees and there is very little "tumbling" or drag there.
it's all done with the shape of the air foils doing the work and the pressure at which it is performed.
Granted most brakes are not designed like air foils but i know there is at least one that is.
Your correct If your break has a opeaning Of 150 thousands and tapered back at 11 degrees it will reduce more recoil then the same size with a 45 degree .
For many years a target crown was 11 degrees . Now it is from flat to 11. Degrees . A wing on a air plane is 11 degrees or less for a reason .
I have a book on brakes I will find it and tell you who wrote it . Larry
Alex Wheeler
Site $$ Sponsor
Physics aside. I have installed and shot many brakes. Theres a huge difference between a brake with ports that are perpendicular to the bore and one with back rake. Night and day difference in recoil reduction. Brake diameter helps too but, put some back rake on those ports and you have an effective brake.
carlsbad
Lions don't lose sleep over the opinions of sheep.
Love it when experimental data backs up the physics. --Jerry
When I was in college, I had several professors that always tried to over-explain their concepts. As mikecr pointed out, the high velocity gasses hitting a wall is what slows the rearward motion of the rifle. (your A1 acceleration) This force accounts for the greatest amount of the recoil reduction, and can be accomplished with very simple designs. (ie JP) Yes, you can increase the efficiency by redirecting the gasses after they initially impact the brake, But it usually requires a more sophisticated design, although many elegant and effective designs are out there.
"All of the devices tested worked on the principle of intercepting a part of the muzzle blast after it left the muzzle and turning it sideways or backward. This is a promising idea, for over one-fourth of the recoil velocity of the average high powered rifle is caused by the rocket-like thrust of the jet of powder gas that rushes out at high speed as soon as the bullet leaves. If we could suppress this effect entirely, we would reduce the recoil velocity of the gun by approximately one-fourth and as the recoil energy is proportional to the square of the recoil velocity, anything that reduced the velocity one-fourth will reduce the energy by nearly 44 per cent."
"Of course we could hardly expect to trap all the gas and take away its reaction as it leaves the muzzle, for we have to leave a hole for the bullet to go through, and a large part of the gas is sure to follow the bullet out a high velocity."
"However, that portion of the gas we do catch can not only be stopped from giving its rearward push, but can, in addition, be made to do work in the opposite direction and give an actual forward push on the gun. This is accomplished bu so shaping the vanes of the muzzle brake that they will turn the gas back toward the rear. If the blades of the muzzle brake are shaped like the blades of an ideal turbine, they could in theory absorb up to twice the momentum of the gases they trap. First they could extract all the momentum by bringing the gases to a stop, then they could absorb an equal amount of work giving the gases the same momentum in a rearward direction. Of course no brake is this efficient in actual practice." Hatcher's Notebook (3rd ed); Julian S. Hatcher, pp. 264-265
Hatcher then goes on to explain that the Army did not adopt muzzle brakes for general use because of the objectionable back-blast.
"Of course we could hardly expect to trap all the gas and take away its reaction as it leaves the muzzle, for we have to leave a hole for the bullet to go through, and a large part of the gas is sure to follow the bullet out a high velocity."
"However, that portion of the gas we do catch can not only be stopped from giving its rearward push, but can, in addition, be made to do work in the opposite direction and give an actual forward push on the gun. This is accomplished bu so shaping the vanes of the muzzle brake that they will turn the gas back toward the rear. If the blades of the muzzle brake are shaped like the blades of an ideal turbine, they could in theory absorb up to twice the momentum of the gases they trap. First they could extract all the momentum by bringing the gases to a stop, then they could absorb an equal amount of work giving the gases the same momentum in a rearward direction. Of course no brake is this efficient in actual practice." Hatcher's Notebook (3rd ed); Julian S. Hatcher, pp. 264-265
Hatcher then goes on to explain that the Army did not adopt muzzle brakes for general use because of the objectionable back-blast.
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carlsbad
Lions don't lose sleep over the opinions of sheep.
The back blast is objectional to the spotter or the infantryman beside you, rather than the shooter. So what muzzle brake in on the 300WM M24?
The Remington 700P in 338LM has a small drilled muzzle brake and is basically unshootable.
--Jerry
The Remington 700P in 338LM has a small drilled muzzle brake and is basically unshootable.
--Jerry
Thauglor
Silver $$ Contributor
Can you post some math or diagrams showing 45 degrees is most efficient?
No offense, but you are just restating things that have all been said before. I agree with most of it, but nothing new here.
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I'm with johnfred and mike......and yes, I own recoil sleds and I test them all.
And more importantly, my testing agrees with all the other recoil sled guys on youtube and elsewhere.
I'ma make it real simple. Read it again from above, the high velocity gasses hitting a wall is what slows the rearward motion of the rifle... THIS is how muzzle brakes work.
period.
To really "get it" walk around the corner of a building into the wind while carrying a sheet of plywood, or a hunk of cardboard, or just open your coat in a strong wind. In simple fact ALL OF THE RECOIL comes from accelerating the "ejecta" (bullet and powder) down the barrel and ALL OF THE BRAKING comes from the powder gas "wind" blowing on the plates of the muzzle brake. The larger the plates (sheet of plywood) the more "braking" effect.
period.
And BTW, in the real world angle has much less effect than redneck logic would seem to imply......(think carrying a satellite dish VS a sheet of plywood) there's actually very little "racetrack" or "slingshot" gas reversal effect. SIZE IS EVERYTHING in brakes and a really large (effective) commercially available brake will present 3", 4" even 6 square inches of "impingement area" (sheet of plywood)
ALL of the recoil attenuation occurs after the bullet leaves the bore and for it to work properly there must be a large wad of gas left over to make the "wind" to pull the rifle off of you....If a rifle isn't "overbore" enough to make lots of gas, the muzzle brake can't do much.
Ya want proof? Come over and shoot my 50BMG versus my subsonic 50. I have built the worlds largest muzzle brake at over 25 square inches of "plywood sheet" and it won't pull my liddle 50 off, it kicks like a MULE at over 70fp. The same brake makes a 50BMG into a pussycat, my aged grandm'ither could wakk zombies all day with it, but drop it down to 1000fps and make it burn all the powder and it'd break her neck. F'real....
Thauglor
Silver $$ Contributor
Wrong on both of your accounts. Those are not the only forces acting on the gun.
If you can accelerate some of the gas to go backwards, you will reduce recoil eben more.
There is also recoil from the pressure in the bore that is acting on the bolt face as the bullet leaves the muzzle.
You are correct that the larger brakes offer more recoil moderation.
And BTW every time somebody spouts drivel about "jet effect" and "rocket-like thrust" etc etc it just makes me cringe......a rocket IS a rifle and vise versa. But the "thrust" starts at the chamber and is produced by ONE thing, the acceleration of the ejecta.
period.
"For every action there is an equal and opposite reaction"
I BEG of you people to do some testing, it's dead easy. I fireform a lot (thousands) of cases using powder and no bullet. I use all sorts of different powders from just covering the primer to almost filling the case for different reasons, cases and situations. PLEASE do this. Make up some "rockets" and go fire them in the yard. You can knock pinecones off the trees, you can harvest your apples from the porch. You can take the muzzle brakes off and on and offagain, you can make jet plumes that reach into the night sky like fireworks.
But what you CANNOT make is much recoil.
please try it.
period.
"For every action there is an equal and opposite reaction"
I BEG of you people to do some testing, it's dead easy. I fireform a lot (thousands) of cases using powder and no bullet. I use all sorts of different powders from just covering the primer to almost filling the case for different reasons, cases and situations. PLEASE do this. Make up some "rockets" and go fire them in the yard. You can knock pinecones off the trees, you can harvest your apples from the porch. You can take the muzzle brakes off and on and offagain, you can make jet plumes that reach into the night sky like fireworks.
But what you CANNOT make is much recoil.
please try it.
Alex Wheeler
Site $$ Sponsor
I recently swapped brakes on my 28 Nosler. 3 port with perpendicular ports to a 4 port with back rake. The volume of the all the ports on the 3 roughly equal that of the 4 and the diameter was about equal as well. I was blown away at the difference. If going from that 3 port with perpendicular ports to the 4 with back rake didnt cut recoil in half Id be amazed. Thats all I need to know. Most every large brake meant for magnums has back rake. They must think it works.
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