Hi Marty,

I've been thinking that having side-vents that had an angled front edge might have some downforce associated with it.
Such as this kind of parallelogram shape

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In an attempt to keep muzzle-rise lower.
As the gas is coming forward behind the bullet, and exiting out the sides, it will blast against the front wall of the vent, and the angle will apply a downward and forward force on the brake when the blast of gas impinges on that front vent wall.

Also, I think that the small vents on top will perform less of this function, because the side vents are so large that the gas will tend to exit there, and not nearly as much thru the smaller restricted vents on top.

I realize the machining is more complex.
Just a thought.

Quoted: Based on TWL's input, made some changes. img.photobucket.com/albums/v617/martytw/50calMB2.jpg While the top vents may seem not that crucial, please note the design of the JP Bennie Cooley brake (LINK) and the MSTN QDB www.pri-mounts.com/mm5/graphics/images/05-0088.jpg The thread choice of 15/16 x 20 is 1) it is UNEF 2) any 0.936 barrel can have it done 3) barrels with smaller threads can take an adapter and make it fit. Tom, this what you had in mind?

Yes Marty, that is just what I was thinking of.
I think that a forward and downward force vector applied by the gasses on the front vent wall will work.

I realize that the Cooley brake and other brakes utilize the small top vents, and I'm sure that they do perform some function. However, to my empirical thinking, the desired "high pressure jet" they they are supposed to perform is questionable in my mind, because there is such an easy path out the side that I don't know if they will really do what is intended(or as much as is wanted). I think the gas pressure is more likely to take the easy exit out the sides, and not as much thru a restricted pathway. I think only an overload of volume out the side ports will cause gas to come out the top in any really significant amounts. Of course, some will, and it might be all that is needed, so experimentation would be needed to see.

However, I do think that a dual-force vector on the brake, which is provided by the slanted front walls of the side vents will help to decrease muzzle rise, and still give the forward push that will perform as a brake.  You should be able to make balancing adjustments in down/forward forces by playing with this angle. 45 degrees will give you equal down force and front push. Interestingly, since it is slanted, it will have somewhat of a smoother delivery of the gas into the vents, because of that, just like the ports in a 2-stroke engine cylinder. The gas will vent into the bottom portion of the vents very slightly ahead of the top portions of the vent, due to this "progressive timing" nature of the slant porting. It could result in a smoother shooting brake. In fact, I see now that you have already implemented a "dual angle" port setup, with different angles on the rear ports and front ports. That looks like a cool idea, since gas pressures will be different at each location, and the needs of the "type of forces applied" may change over the length of the brake. From what I see in your drawing, you are going for heavier braking at the rear port where the pressure is the highest, and going for more downforce at the front port where leverage will help in reducing muzzle rise. Good plan.

One thing that might be a nice addition would be an optional disc-type blast shield that could be put onto the barrel behind the brake installation like a washer. A little bit of extra diameter washer behind the brake can go a long way to reducing sound and blast back at the shooter. With a large fender washer or something, it would be something that only the people who want it would put it on, This option would  allow blast shielding for those who might want it, and not cause problems with people who don't want one. It could just be a simple large diameter fender washer, put on where the peel-washer is now. Remember the angular formula, and a couple of inches  in diameter of a shield behind the muzzle brake would translate into a fairly good sized cone of blast protection at the shooter position. Making it an optional add-on would eliminate any consumer objections from those who don't want it. Personally, I like to reduce the blast and sound at my face and ears when using a brake.

And, I also think that this vent shape as shown in your drawing has a very cool "high-tech" look to it, that sets this brake apart from the crowd of brakes that all look the same, and can give an easily recognizable and unique appearance to your product.

Marty-

My thoughts on threading...

3/4-20 or 7/8-20 would both be good choices being NEF standards.
I don't like the idea of going all the way to 15/16" on a bull  barrel.
Many bull barrels are only about 0.920" out in front so you end up with no torque shoulder to snug the muzzle device against.
Maybe this is intentional and you will have a shoulder inside the brake to torque against like a Smith Vortex?
3/4-20 or 28 gives you a nice torque shoulder, but 7/8"-20 might be a really good compromise of wall thickness at the thread's minor diameter while still haveing a torque shoulder.

I would be in for one for my .50 Beuwolf.  I would prefer it in the same finish as the barrel though instead of stainless.  Is this possible?

Also, my barrel will need to threaded, can you help with this and what would the cost be?

Count me in for one that is matched to the parkerizing then and I will work on getting the barrel threading done.  All I will need is the thread pitch when that is finalized.

Thanx!

Quoted: Randall, roger on the thread, forgot about some of the 0.92 folks.  7/8 x 20 would be best as that would allow some adapters for a few 3/4 x 20 and 3/4 x 28 barrels I have sent out previously.

Oh come on, don't take the easy route and make adapters...
Just make a few brakes with the smallest threads they would ever be used on and make the rest of them to the thread spec you choose for future builds.
Then you can take those small ones and open them up on a case-by-case basis as required for the past customers who end up wanting them.

Not to Hijack work from Tony, but I can certainly thread barrels for you guys as well...

Mart-

I don't like the bevel up front.
Since the brake HAS to be indexed with the force vectors and the little top vent, how about something like this with an angle cut front face:

I like the looks of the original design but will be happiest with whatever works better.

Quoted: ETA:  I would be interested in something that cuts muzzle climb as a PRIMARY function.  Recoil reduction would be a secondary concern.

I agree with Shivan.  I am running a hydraulic buffer that helps with recoil (although a little extra help would not hurt on the .50 Wulf).  I am more interested in muzzle climb as well.  

The rear of this design needs a bevel that will blend down to the barrel like a JP Bennie Coolie comp.

Quoted: Randall - the angled design looks interesting but I would have to agree with Sako, as shown the design would INCREASE muzzle lift.  If you add large vents on top the gas jet would serve to force the muzzle down and it would work. I can make the front bevel far less pronounced and maybe add a reverse (target) crown or counter bore instead .... Last revision, I think this might actually be the best looking one ... img.photobucket.com/albums/v617/martytw/50calMB2b.jpg img.photobucket.com/albums/v617/martytw/50calMB2Bf.jpg I had a moment of clarity (or was that a bottle of Claret) and realized Ned over at MichiGunshas done several brakes like this.  Look under Rifle, Shotguns, etc as well as AR-15s, and also his photo album.  I love Neds work, especially his alternate approaches to checkering and stippling.  Some day when I have lots of time I will try and build my next 1911 and have him do the surface work.

New design looks good.  As stated before, muxxle climb being first priority with the benefit of a brake for less felt recoil.  I am ready for it when you have them.

Still want mine parked for barrel match!

Marty,
I think it looks real good.
I'd say go with it.

Any word on these brakes?  Just wondering when I should make arrangements to get my .50 Wolf barrel in for threading.  

Quoted: Quoted: Any word on these brakes?  Just wondering when I should make arrangements to get my .50 Wolf barrel in for threading.   The order is beinf processed and it should take about 4 weeks so I would guess 3 more weeks?  When they come in I will post a picture including one on a scale to show how much weight they add.

Please make sure one is reserved for me.  Still good for the parked finish to match the barrel also?

Thanx!