BJH65
AH enthusiast
I believe there are some misconceptions about Mag-na-port, a system devised by Larry Kelly back in the 60’s utilizing Electrical Discharge Machining (EDM) machining 4 trapezoidal ports, 2 on each side offset, became popular back in the 70’s-90’s on large bore revolvers and hard kicking rifles.
I have owned several used rifles that already had Mag-na-porting: 300 Weatherby MK V, 338 Wn Mag Ruger M77 tang safety and a custom Brno ZKK-602 458 Lott. The first two had the traditional 4 trapezoidal ports and the 458 Lott just two trapezoidal ports primarily to control muzzle rise.
I want to be clear as possible, there is no significant increase in noise and muzzle blast with the Mag-na-porting when compared to my other rifles of similar caliber without porting although I can only compare my un-ported CZ 416 Rigby to my Brno 458 Lott and my other. various non ported 300 magnums to the 300 Weatherby with Mag-na-porting. I have a backyard range and my wife can confirm this as well. Let me repeat this one more time, these is no notable difference and especially with my 458 Lott with only the two trapezoidal ports.
Many on AH lump Mag-na-port with KDF, Weatherby Accubrake, and many other traditional muzzle brakes. They do this because I believe they are simply uninformed. KDF style muzzle brakes are much more effective at reducing felt recoil than Mag-na-port but at a cost: significantly more muzzle blast and noise, the kind of noise without hearing protection that will certainly make your ears ring, is harmful to hearing and very distracting/annoying to your PH.
It’s been estimated by others including the late gun writer Ed Matununas, that Mag-na-port reduces felt recoil by 1/3rd perhaps more the larger the caliber. Less than traditional muzzle brakes, which is why Mag- a-port isn’t so popular these days, but enough reduction to make a difference to many recoil sensitive shooters, allowing them to shoot more comfortably. Matunas felt it was a very viable option for African big bore rifles while he eschewed the more traditional KDF muzzle brakes due to increased muzzle blast and noise.
Where I truly believe Mag-na-port shines is significantly reduced muzzle rise allowing one to make quick follow up shots, certainly a huge asset in a charge. I recently did a one rifle safari with my CZ 416 Rigby. I shot a warthog that dropped immediately to the shoulder shot (very clear in the video footage) but since a was in full recoil I didn’t see him drop and when another warthog nearby ran directly at us, I thought for a second he was wounded and charging us!
That warthog was simply fleeing from all the commotion and didn’t know where we were. Had my rifle been Mag-na-ported I would have seen the impact of the shot of the immediately downed warthog. For those that want a DG rifle with reduced muzzle rise, I see Mag-na-port as a very viable option and it may reduce felt recoil just enough to make it tolerable without the horrible noise and muzzle blast of the other more effective recoil reducing muzzle brakes.
I also find the Mag-na-port to much less obtrusive than the other KDF style threaded muzzle brakes that are easily visible and often add several inches to the rifle barrel. The Mag-na-port add nothing and is not as noticeable, doesn’t visually change the lines of the rifle to me. In fact I got a most excellent bargain on a wonderful custom AHR/Robar Brno 458 Lott on AH because many eschewed the Mag-na-port on this rifle. Well, good for me, otherwise I would not have this rifle which I will be taking on our 2026 Safari for buffalo, hippo and maybe lion.
Would I personally have Mag-na-porting done on my other rifles? No, because I can tolerate the recoil and feel I am effective with them without Mag-na-porting but I wouldn’t hesitate to buy a used rifle that already had this done. The only perceived drawback I can see is the notion held by many that it reduces the value of the rifle for investment purposes. These same folks incorrectly believe Mag-na-ported rifles significantly increase noise and muzzle blast but I would ask them: have you fired a Mag-na-ported rifle side by side with a non Mag-na-ported rifle like I have? Noise and muzzle blast negligible and no PH would complain anymore than a non Mag-na-ported rifle.
Some photos showing the difference.
Mag-na-port
Tradional KDF muzzle brake
I have owned several used rifles that already had Mag-na-porting: 300 Weatherby MK V, 338 Wn Mag Ruger M77 tang safety and a custom Brno ZKK-602 458 Lott. The first two had the traditional 4 trapezoidal ports and the 458 Lott just two trapezoidal ports primarily to control muzzle rise.
I want to be clear as possible, there is no significant increase in noise and muzzle blast with the Mag-na-porting when compared to my other rifles of similar caliber without porting although I can only compare my un-ported CZ 416 Rigby to my Brno 458 Lott and my other. various non ported 300 magnums to the 300 Weatherby with Mag-na-porting. I have a backyard range and my wife can confirm this as well. Let me repeat this one more time, these is no notable difference and especially with my 458 Lott with only the two trapezoidal ports.
Many on AH lump Mag-na-port with KDF, Weatherby Accubrake, and many other traditional muzzle brakes. They do this because I believe they are simply uninformed. KDF style muzzle brakes are much more effective at reducing felt recoil than Mag-na-port but at a cost: significantly more muzzle blast and noise, the kind of noise without hearing protection that will certainly make your ears ring, is harmful to hearing and very distracting/annoying to your PH.
It’s been estimated by others including the late gun writer Ed Matununas, that Mag-na-port reduces felt recoil by 1/3rd perhaps more the larger the caliber. Less than traditional muzzle brakes, which is why Mag- a-port isn’t so popular these days, but enough reduction to make a difference to many recoil sensitive shooters, allowing them to shoot more comfortably. Matunas felt it was a very viable option for African big bore rifles while he eschewed the more traditional KDF muzzle brakes due to increased muzzle blast and noise.
Where I truly believe Mag-na-port shines is significantly reduced muzzle rise allowing one to make quick follow up shots, certainly a huge asset in a charge. I recently did a one rifle safari with my CZ 416 Rigby. I shot a warthog that dropped immediately to the shoulder shot (very clear in the video footage) but since a was in full recoil I didn’t see him drop and when another warthog nearby ran directly at us, I thought for a second he was wounded and charging us!
That warthog was simply fleeing from all the commotion and didn’t know where we were. Had my rifle been Mag-na-ported I would have seen the impact of the shot of the immediately downed warthog. For those that want a DG rifle with reduced muzzle rise, I see Mag-na-port as a very viable option and it may reduce felt recoil just enough to make it tolerable without the horrible noise and muzzle blast of the other more effective recoil reducing muzzle brakes.
I also find the Mag-na-port to much less obtrusive than the other KDF style threaded muzzle brakes that are easily visible and often add several inches to the rifle barrel. The Mag-na-port add nothing and is not as noticeable, doesn’t visually change the lines of the rifle to me. In fact I got a most excellent bargain on a wonderful custom AHR/Robar Brno 458 Lott on AH because many eschewed the Mag-na-port on this rifle. Well, good for me, otherwise I would not have this rifle which I will be taking on our 2026 Safari for buffalo, hippo and maybe lion.
Would I personally have Mag-na-porting done on my other rifles? No, because I can tolerate the recoil and feel I am effective with them without Mag-na-porting but I wouldn’t hesitate to buy a used rifle that already had this done. The only perceived drawback I can see is the notion held by many that it reduces the value of the rifle for investment purposes. These same folks incorrectly believe Mag-na-ported rifles significantly increase noise and muzzle blast but I would ask them: have you fired a Mag-na-ported rifle side by side with a non Mag-na-ported rifle like I have? Noise and muzzle blast negligible and no PH would complain anymore than a non Mag-na-ported rifle.
Some photos showing the difference.
Mag-na-port
Tradional KDF muzzle brake
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