I like this idea for my standard Rem 700 BDL 338 WM, opposed to the Vais radial.
allen 5 port muzzle brake vs factory one
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I like this idea for my standard Rem 700 BDL 338 WM, opposed to the Vais radial.
Fiftydriver
Official LRH Sponsor
The big 5 port is designed for the 408 CT so its not really in the same usage class as the smaller brakes, just for use with different chamberings so not really able to compare the two head to head. The Large 5 port needs +120 grs of powder charge to make it worth going with over the medium PK.
Fiftydriver
Official LRH Sponsor
The Rem 700 BDLs have barrels large enough to use my small PK and they work GREAT. The micro PK idea would be for some of the ultralight rifle packages.
KRL1116
Well-Known Member
Kirby
What about splitting the diffence and make a smaller version with Four ports? May cut down the length a bit and still have more surface area! Just a thought.
Kev
What about splitting the diffence and make a smaller version with Four ports? May cut down the length a bit and still have more surface area! Just a thought.
Kev
Fiftydriver
Official LRH Sponsor
Muzzle brakes work in an interesting way, especially a partition style muzzle brake like the Painkiller. If you take a chambering such as my 338 Allen Xpress(338 Lapua Improved), you will see roughly the following performance with my PK muzzle brakes. This is using a powder charge of roughly 95 to 100 grains of powder(H-Retumbo) under a 250 to 300 gr bullet weight. This is also using a barrel length in the 26 to 28" length. This is somewhat important which I will explain more on later.
The first port runner, the one closest to the muzzle does about 60% of the work. By that I am saying that roughly 60% of the muzzle gas gets bled off through this first port. About 20% of the escaping muzzle gas is bled off through the second port and the third port removed less then 10%. Its a pretty good rule of thumb that each runner will remove roughly 1/3 the gas as the one before it for the first 4 ports, after a 4th port, you are only looking at less then 5% of the escaping muzzle gas that actually get to that distance away from the muzzle. Again, this is for a case with roughly a 100 gr powder charge.
So what does this mean, simply put, you will get no more effect at reducing felt recoil by adding more partitions unless the cartridge powder charge is increased dramatically OR barrel length is reduced significantly.
This is easy to see just by looking at a muzzle brake that has been used. The first runner will have a heavy build up of carbon fouling, the second partion will have a noticably lighter carbon build up. The third port will have VERY little carbon build up.
I have fitted a few of my large 5 port PK muzzle brakes on some conventional rifles and the last two paritions will often stay clean from any carbon build up with cartridges of 100 grains or less, especially if your using a modern stick powder which burn very clean. Some of the ultra slow ball powders will show more carbon build up but thats simply because they are Dirty burning.
Now, dramatically shorter barrels will change everything about what I have just said because of the dramatic increase in muzzle pressure because of the shorter barrels. For example, I have built several custom XP-100 bolt action handguns chambered in my 338 Allen Xpress. These are SERIOUS handguns producing 2700 fps class performance with the 300 gr SMK in 15-16" barrel lengths. With this class of chambering in these very short barrels, the large 5 port brakes can be used to full effect.
Why explain all this, simple, You could add another partition to the medium and small PK but you would not increase the effectiveness of the muzzle brake at reducing felt recoil but you would increase the manufacturing time (COST) with no improved performance level.......
Thats why I do not have a four port PK in the medium and small sizes, no advantage from what I have seen in my testing. When I was developing my PK muzzle brakes, I had several different prototypes including 4 and even 5 port small PKs, they showed no advantage at all over the 3 port PK and added another 3/4" to their length and also added 40% in manufacturing time over the 3 port PK design. If I am going to charge my customers more, it will be for a reason, so customers actually get a good return for their investment so the 3 port Medium and Small PK was the best of all prototypes tested.
The first port runner, the one closest to the muzzle does about 60% of the work. By that I am saying that roughly 60% of the muzzle gas gets bled off through this first port. About 20% of the escaping muzzle gas is bled off through the second port and the third port removed less then 10%. Its a pretty good rule of thumb that each runner will remove roughly 1/3 the gas as the one before it for the first 4 ports, after a 4th port, you are only looking at less then 5% of the escaping muzzle gas that actually get to that distance away from the muzzle. Again, this is for a case with roughly a 100 gr powder charge.
So what does this mean, simply put, you will get no more effect at reducing felt recoil by adding more partitions unless the cartridge powder charge is increased dramatically OR barrel length is reduced significantly.
This is easy to see just by looking at a muzzle brake that has been used. The first runner will have a heavy build up of carbon fouling, the second partion will have a noticably lighter carbon build up. The third port will have VERY little carbon build up.
I have fitted a few of my large 5 port PK muzzle brakes on some conventional rifles and the last two paritions will often stay clean from any carbon build up with cartridges of 100 grains or less, especially if your using a modern stick powder which burn very clean. Some of the ultra slow ball powders will show more carbon build up but thats simply because they are Dirty burning.
Now, dramatically shorter barrels will change everything about what I have just said because of the dramatic increase in muzzle pressure because of the shorter barrels. For example, I have built several custom XP-100 bolt action handguns chambered in my 338 Allen Xpress. These are SERIOUS handguns producing 2700 fps class performance with the 300 gr SMK in 15-16" barrel lengths. With this class of chambering in these very short barrels, the large 5 port brakes can be used to full effect.
Why explain all this, simple, You could add another partition to the medium and small PK but you would not increase the effectiveness of the muzzle brake at reducing felt recoil but you would increase the manufacturing time (COST) with no improved performance level.......
Thats why I do not have a four port PK in the medium and small sizes, no advantage from what I have seen in my testing. When I was developing my PK muzzle brakes, I had several different prototypes including 4 and even 5 port small PKs, they showed no advantage at all over the 3 port PK and added another 3/4" to their length and also added 40% in manufacturing time over the 3 port PK design. If I am going to charge my customers more, it will be for a reason, so customers actually get a good return for their investment so the 3 port Medium and Small PK was the best of all prototypes tested.
KRL1116
Well-Known Member
Thanks for the info, I learn something new everyday. I would have to say that it would be hard to improve your PK's, I feel they are the best there is and the only brake I will use! On a another subject, are you still interested in doing that A-bolt 4 me?
Kev
Kev
kc0pph
Well-Known Member
I have a 338-378 on the way. I believe it will be using around 106 or so grains of ThunderBird 870. That is getting close to the 5 port requirements. Now It has currently the factory Brake and Barrel from WBY but soon will be made with a heavy barrel of 30" or so. This is when i will buy a new brake to put on it. What would be the best one to put on. I am also considering the CSR MuzzleBrake, which would be better?
SavageShtr
Well-Known Member
I would think you would only need the three port medium painkiller for your 338-378. The five port is designed for a 130gr of powder and above!!
