shotgun barrel milled like suatev muzzle break?

[saltydecimator 482]

seems the chopping threading then welding takes buncha effort, and perhaps extra cost?  what are the reasons for not just milling the barrel?  wad petals get caught?

 

the milling be pretty straight fwd, i just dont understand the rocket science part of it...

https://www.legionusa.com/vepr-saiga-12-sutaev-muzzle-brake.html

[Rhodes1968 1,638]

NM brain fart

Edited October 14, 2017 by Rhodes1968

[gunfun 3,931]

The cross section of angles surfaces has a mathematical relationship to the potential for gas vectoring. There's a naval/ artillery whitepaper giving all the formulas. The short answer is that if you want to counteract recoil and not just flip, you have to leave some area for the gas to push against more or less in the way of its origninal vector. The really thin comps do poorly for this reason. 

 

It's rapidly diminishing returns. Basically the first about inch and a half of ports/ vectoring surfaces do work, then the pressure being applied to any remaining surfaces drops off logarithmically. IMO, the comp at the top is made backward, vent most of the working pressure before any of the gills. a thinner walled version has less gill surface area.

 

I'm from a boat building family, and this stuff works very similar to a rudder. You are essentially blocking a high pressure area with a controlled vent in a new direction. That creates a low pressure, and a fluid nozzle (like a rocket motor). The open ports on the top thrust down, but they don't pull forward significantly, since the perpendicular area on their front edges is very small, and they are wide open. Adding those features after there is no gas left to work with is pretty much cosmetic.

[G O B 3,516]

Comps actually work similar to gas turbines. To produce a torque in reaction to a fluid (gas), you are pushing against an area( ), with a gas at ( ) PSI, with ( ) viscosity) and a velocity of ( )times ( ) time = force

 

 Like a sail on a boat, bigger sail gives more torque. 

[gunfun 3,931]

Comps actually work similar to gas turbines. To produce a torque in reaction to a fluid (gas), you are pushing against an area( ), with a gas at ( ) PSI, with ( ) viscosity) and a velocity of ( )times ( ) time = force

 

 Like a sail on a boat, bigger sail gives more torque. 

 

Yep, and a big sail with almost no wind does a lot less than a medium sail in a strong wind.

[evlblkwpnz 3,418]

+1 GunFun

 

After I get done with CNC school and things are caught up at both companies, maybe I can whip something up based on what actually works, not looks. However, the beauty of great function is often that great form will follow.

[Ronin38 2,117]

What's the general consensus on compensator holes drilled in to the barrel? I've seen several new shotguns that have patterns of holes drilled to (hopefully) reduce muzzle rise. Do these work well, and is there an accepted pattern to follow?

 

Is Mag-Na-Port still in business? I have a T-C Encore 22-250 that my Dad had the barrel ported this way.

[evlblkwpnz 3,418]

What's the general consensus on compensator holes drilled in to the barrel? I've seen several new shotguns that have patterns of holes drilled to (hopefully) reduce muzzle rise. Do these work well, and is there an accepted pattern to follow?

 

Is Mag-Na-Port still in business? I have a T-C Encore 22-250 that my Dad had the barrel ported this way.

It apparently adds at least some benefit. There are drilling jigs for that work.

 

 

https://www.brownells.com/gunsmith-tools-supplies/shotgun-tools/barrel-porting-jigs/barrel-porting-jig-prod15478.aspx

[Ronin38 2,117]

Thanks, but $286 costs more than the shotgun at this point! 

[gunfun 3,931]

For what it's worth, Vadim did a video recently which does a good job of comparing some of the trendy ruskie style comps lately. Sutayev was one of them. It did a little better than I would have expected, but unsurprisingly did more to reduce flip than recoil. downward thrusting vents got the high pressure gas, and the forward pulling vents got the low pressure. I think it could have been achieved more compactly, in a similar layout simply by using smaller slots for the downward thrust.

[G O B 3,516]

The only  reason I can see for drilling holes near the muzzle on a shotgun is to relieve the pressure on the wad before it exits the muzzle. This may effect the pattern.

[saltydecimator 482]

ah ya i forgot about surface area... or forgot  about that thats important....

[saltydecimator 482]

gunfun i would get more outta what you say with pictures, ahhahaahh

[gunfun 3,931]

gunfun i would get more outta what you say with pictures, ahhahaahh

 

That would take more time than I had that day. To be honest, I was posting to avoid for a few minutes doing the pressing load of work I had that was stressing me out. 

 

I've gotten some of that out of the way, but maybe I can draw some sketches up tomorrow.

[saltydecimator 482]

oh no, im not requesting it, im just a visual learner or whatever?  i mean i mostly grasp what youre sayihng, but if it was a picture i would know instantly....  and my wife took most of my college physics class, i failed every test but loved the class! she aced everything and hated the class cause of the prof's sense of humor, haha

[gunfun 3,931]

The only  reason I can see for drilling holes near the muzzle on a shotgun is to relieve the pressure on the wad before it exits the muzzle. This may effect the pattern.

 

Reduced recoil, faster followup. Also as you said, less pressure on the wad at exit. This can be a good or bad thing depending on wad type and what you expect the spread to do.

 

"Wad strippers" tend to work by venting the pressure before the crown, then having something grip the wad a little to slow it slightly on exit. That gets a fast spread. 

 

Other chokes won't be greatly effected.

oh no, im not requesting it, im just a visual learner or whatever?  i mean i mostly grasp what youre sayihng, but if it was a picture i would know instantly....  and my wife took most of my college physics class, i failed every test but loved the class! she aced everything and hated the class cause of the prof's sense of humor, haha

 

You've kinda given me a challenge. I've been thinking of how I could improve my communication and quickly make simple visuals to convey ideas like this. Some of the content producers I appreciate the most are not more knowledgable than others about the subject matter. They are more efficient with clear uncluttered visuals. i.e. "Clint Westwood", "This Old Tony" etc. If I come up with a good way to show what I mean in picutures, I might make a quick vid. It's been too long anyway.