Two brake questions.

T

tjensen

New member
Hi friends.

#1
I have been looking at muzzle brakes. Some seem to have the holes sloping towards the target, Mine have a 7 degree slope towards the target.
But googling brakes I have seen them point towards the shooter?
And some are just 90 degrees.

Wich will work the best by your experience?

#2
Bill Holmes in one of his books claims that they should be at 90 degrees, however they should have a "chamber", the bigger the better as the effect is from the gasses slamming against the wall surrounding the exit hole.
Any comments on that?

Thanks in advance.
 
I believe the slightly forward facing vent holes may defect some of the 'blast' away from the shooter yet still reduce recoil greatly. I also believe a larger brake diameter works better than small brakes or Magna-Porting in reducing recoil.

On a hunting rifle this brake works really well. Ports slightly forward and about .700" diameter. This is on a skinny .300 Short Mag barrel...
thinbarrelmattebrake-0.jpg
 
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alinwa said:
Bill Holmes is right
Click to expand...

Al, We've discussed brakes before and I'm not looking to debate them now, but am curious. What does an expansion chamber do to help the performance of a brake. I would think you would want to scavenge the gasses while at a high velocity. Wouldn't an expnasion chamber reduce that velocity?--Mike
 
The "expansion chamber" just offers more surface area against which the gas can impinge. More surface area="bigger sail"=more recoil countering effect.

I built a recoil sled today.... trying to design a quiet muzzle brake..... and crudely measure mitigation effect of various designs. Hopefully Monday I'll have some results.

al
 
alinwa said:
The "expansion chamber" just offers more surface area against which the gas can impinge. More surface area="bigger sail"=more recoil countering effect.

I built a recoil sled today.... trying to design a quiet muzzle brake..... and crudely measure mitigation effect of various designs. Hopefully Monday I'll have some results.

al
Click to expand...

Thanks Al. I'd be interested to know the results with your sled between a brake similar to the one pictured above, with and without an expansion chamber.--Mike
 
There's no room in a brake like that for a chamber. Not much of one anyhow.

Of the brakes I made and tried, the ones with the cone shaped inside seemed to work the best. Not that I liked any of them.

The mass of the powder is what you get to work with using a brake. If you have 60 grains of powder, plus a 190 bullet, there's 250 grains total. You can have the full mass going forward, or you can vent 60 of it to the side. The more of that 60 you can vent sideways, the less felt recoil there will be. In the above example, you can hope to reduce recoil by a theoretical 24%. How efficiently that can be done is anyones guess.

The military uses ones with big chambers on tanks and artillery, so something tells me they work the best.
 
On a factory Sako hunting rifle in .338 Win Mag... a brake as pictured above reduces recoil tremendously... it kicks way less than a factory 700 BDL in 30-06.
 
On my web page I have an article I wrote about Muzzle Brakes. It could us some updating as I have a little more info at this time. But the basics have not changed.

www.rvbprecision.com

I built a recoil sled using a mechanical strain gauge. It did not give me accurate pounds or oz of recoil, but it could be used to see the difference various design results.

The most effective muzzle brake, by far, was this one

ar15.jpg


Small exit hole with huge "blast barrier" and large side gas escape holes. On a 223 or a 220 Swift, the recoil on a 10 pound rifle was nearly zero. The rifle will move back in a rest less than 2". On a 25 pound AR15 (lead in stock and forend), the rifle moves less than an inch. And there is zero muzzle rise on both.

I've found that the smaller the caliber, and the more powder being burned, the more effective all the brakes are. The 220 Swift is the winner in recoil reduction by far! Shot-Guns are the less effective. In handguns (Contenders), the 300 Whisper and 454 Casull show good recoil reduction, but not as effective as the 223, 222 and other in this family.

I did not find expansion chambers to offer any more reduction than simply drilling holes through the sides of the brake. The hole size did have an effect on recoil and noise. Bigger holes reduced recoil more than small, and small holes really increased noise in the higher frequency range which could be really damaging and annoying. With ALL brakes, hearing protection is a MUST!

The type of brakes that are usually found on the 50BMG rifles are very effective

images


The Vias brake is my favorite. Great reduction of recoil and a bit quieter than most.

brakevaisx350op.png


But a brake I find favor with for hunting rifles is one that can be turned on and off and because you don't remove it, your POI doesn't change.........Hunting guides appreciate that you can turn it off if they are laying next to you glassing the game!

Vac1-vi.jpg

Vac2-vi.jpg
 
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4Mesh said:
There's no room in a brake like that for a chamber. Not much of one anyhow.
Click to expand...

That is how I have viewed them. I can see how a really big chamber(like a suppressor) would help but in a typical brake for a hunting rifle, it's hard for me to imagine having enough area to do much good with a chamber.--Mike
 
Thank you all for your replies.
I still have questions though.

I had read your article Roy and wonder if a brake of the shape similar to this one on the photo would work even better if it was bigger still, say, 2" dia, or even3"?

Also.
If the brake works by the gases slamming on the wall, why have bleeding holes on the sides?

Why does the Vais brake have holes on the front then?

Lastly.
Guy Lautard sayz in his chapter on home made muzzle brakes that the size on the exit hole is not that inportant. But everywhere else I read that is indeed inportant.
What do you guys think of that and did you experiment with that also Roy?

Many questions I know but I curious on this subject so I hope you all forgive me.

Regards.
 
Take a look at George Vais' second design muzzle brake at activetuningsolutions.com. The master brakes have a chamber and angled exit holes to project the gases away from the shooter thus muffleing the noise that traditional muzzle brakes emit. The hunters brakes are 3" long and have a much larger chamber and even quieter than the master brakes.
 
tjensen said:
Thank you all for your replies.
I still have questions though.

I had read your article Roy and wonder if a brake of the shape similar to this one on the photo would work even better if it was bigger still, say, 2" dia, or even3"?

Also.
If the brake works by the gases slamming on the wall, why have bleeding holes on the sides?

Why does the Vais brake have holes on the front then?

Lastly.
Guy Lautard sayz in his chapter on home made muzzle brakes that the size on the exit hole is not that inportant. But everywhere else I read that is indeed inportant.
What do you guys think of that and did you experiment with that also Roy?

Many questions I know but I curious on this subject so I hope you all forgive me.

Regards.
Click to expand...

Of course the size of the exit hole is important... that restriction is required for an efficient, effective brake...

The front holes of a brake are to help deflect the noise the shooter hears...

What are you trying to brake ?
 
Not trying to brake any special rifle Dennis.
Been using Brownells brakes on costomers rifles and was thinking about maybe making my own.
I could just copy the Brownells brakes with the 7 degree angle, but 90 degree´s would be simpler to make.
 
Remember that for some 1,000-600 yard competition, rearward facing slots, holes, etc. are illegal. Tle rule reads "no calmshell type brakes," but the rangemaster may rule that includes any rearward facing brake.

Not saying the Schuler is of that design . . .
 
I had read your article Roy and wonder if a brake of the shape similar to this one on the photo would work even better if it was bigger still, say, 2" dia, or even3"?
Click to expand...
I think you reach a point of diminishing returns with the size. There is finite gas available to be moved sideways and counteract rearward thrust of the rifle. But I have made this same brake is 2.5" diameter for an extreme bull barrel AR-15 that I have. What you can't see in the photograph is that the baffle, the area that the gasses slam into, is a 30 degree cone shape.

Also.
If the brake works by the gases slamming on the wall, why have bleeding holes on the sides?
Click to expand...
The gas has to go somewhere. And you don't want it going forward which is what creates much of the recoil when firing the rifle.

Why does the Vais brake have holes on the front then?
Click to expand...
The holes in the front take some of the gasses that would be expanding out of the side, and a few milliseconds after the bullet has left the barrel and directs them forward, spreading out the recoil impulse. This makes the brake a bit quieter (maybe, see below) and it does reduce the muzzle blast back at the shooter quite successfully. Folks shooting to the side of you will appreciate this.....

Lastly.
Guy Lautard sayz in his chapter on home made muzzle brakes that the size on the exit hole is not that inportant. But everywhere else I read that is indeed inportant.
What do you guys think of that and did you experiment with that also Roy?
Click to expand...
I did a ton of experiments with this. I had a Savage 112 in 308 that I used as a test mule. I built a brake and fired it with a couple thousands over bore diameter, then I removed it and increased the size of the hole. Measurable change in recoil happened at .040" over bullet diameter. Any exit hole over .040 and the brake began to lose effectiveness rapidly.

Lastly, this whole idea of muzzle brakes being quieter because the holes have a slight cant forward is suspect. I have access to very expensive Sound Pressure Measurement equipment and one of these days I'm going to borrow it from work and run some tests. I believe it does reduce the amount of perceived muzzle blast, and thereby giving the impression of reduced noise. But any loud noise of the magnitude we are discussing here, happening 26-30" from your ears is gonna be downright LOUD.
 
I disagree with this statement from above;

"The gas has to go somewhere. And you don't want it going forward which is what creates much of the recoil when firing the rifle."

That gas is GONE. It's already produced it's recoil force via Newt's 2nd law..... the only effect it can have on the rifle is if you put a sail out and CATCH IT.

Which is what a muzzle brake does, re-uses spent gas.

There is a small additional recoil impulse generated WHILE the gases are spurting out behind the bullet but not FROM the gases spurting out behind the bullet, except that they move out of the way and let the gas still in the barrel build energy via an accelerative force...... just as if you'd opened the mouth of a child's balloon.

al
 
al,
i think you miis heard what he wrote......i think(dangerous) he was saying you did not what the gas to continue forward uncontrolled, you do want it to hit something(a sail as you say) to minimize recoil.
and the big ho;e brake is very simple and impressive based on the results....think i may make one for my 300 win mag 1000yd gun....

mike in co
 
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