MagnaPort Effectiveness?

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Whitecoyote posted a thread with some beautiful MagnaPort Custom revolvers in it, which got me thinking. (Dangerous, I know!) I've been a handgun shooter for many years. I shot tens of thousands of rounds a year for several years when I was heavily involved in IPSC shooting, much of that through compensated pistols. I've shot lots of ported guns, revolvers and autos alike, with various different porting styles and systems, some with expansion chambers, some without. Presently, I own three revolvers with MagnaPort ports: an 8 3/8" 629 with original-type trapezoidal ports, and two 3" 681+ PC guns with "Quad Ports." The Quad Port guns have a small expansion chamber. I've shot perhaps a half dozen other MagnaPorted revolvers over the years, including at least one 4" Model 29 and a 1911 or two with ports cut through the slide and barrel.

Perceived recoil and muzzle rise are highly subjective, so here are my subjective perceptions, along with a little of the objective: I have never been able to feel any reduction in recoil from the original, two-port trapezoidal MagnaPort design. However, with my 8 3/8" 629, there is a very perceptible reduction in muzzle rise, especially with light bullet, high gas volume loads, and I find that very useful.

My Quad Port .357s are a different breed. Muzzle rise is dramatically reduced, and recoil very noticeably reduced. The hotter the load, the better they work. Remington 125gr. SJHP loads are pussycats in these guns, and that's saying something. I've had to file down the front sights on both guns to get POI up, because muzzle rise is so well controlled.

Question, for those who have shot MagnaPorted guns only, how much, if any, recoil and muzzle rise reduction do you perceive?
 
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I've been to their shop many times, and have had them do work for me over the years. They are good people. That said, the original two port system is a waste of money as far as I am concerned. Rifle or handgun, but especially handgun.

I have had a Marlin 1895 in .45/70 done with the 4 port system that they used to use for rifles (don't know if they have changed that set-up or not), the one with the original ports on either side of the front sight, then two smaller ports below and behind them, at the centerline of the bore. That has worked great for reducing muzzle rise on the Marlin, a Rem 700 Safari Grade in .416 Rem that I bought back when that chambering first came out, and finally on a Ruger SRH in .44 magnum. Recoil felt about the same with all guns, but muzzle rise definately went down, which makes the gun feel less punishing for extended range sessions like I like to put in.
 
I've only ever shot one Magnaported gun, and that is my granddad's 10-1/2" Ruger Blackhawk .44 Magnum. I never shot the gun before it was ported, but I can definitely say it doesn't feel like a .44 Magnum...more like a .44 Special or maybe a full-house .357 Magnum. There's a definite difference.
 
Interesting thread. I have had mag-na-ported guns and thought the porting had minimal effect. A few years ago I bought a Freedom Arms 6" 454 and the porting seems more effective - and maybe that is as noted above about a hotter round. One think I dont like is the black residue on the front sight after a few rounds. If it came that way, then OK, but I dont think I will be sending off any more guns for porting.
 
My perception is that Magnaporting is more effective with higher velocity rounds.

Having said that, I had my .458 Win Mag Magnaported many years ago and was not at all impressed with any recoil reduction that might have resulted from the machining. The Magnaporting was two ports on each side.

I'm sorry I had it done, it just marred the appearance of a classic rifle, a Ruger No. 1. Don
 
I've only ever shot one Magnaported gun, and that is my granddad's 10-1/2" Ruger Blackhawk .44 Magnum. I never shot the gun before it was ported, but I can definitely say it doesn't feel like a .44 Magnum...more like a .44 Special or maybe a full-house .357 Magnum. There's a definite difference.

To be fair, that's kinda of a tough comparison here. The 10 5/8" barrel makes the gun heavier, especially so as far as being muzzle heavy. I have shot 6 1/2" 29's side by side- one ported with the original system, one not. I could see no difference in muzzle rise, nor feel any difference.

In my opinion, Mag Na Port's real strength is their custom gunsmithing abilities. It is first rate!
 
Here's my opinion (not just mine, learned from pro shooters). People confuse compensators with ports because both have ports directing gas upward. The myth is that the upward gas is the reason a compensator reduces recoil/muzzle lift. A good reference on this is contained in Glaxco's book "shooting from within". Muzzle rise is a result of recoil force which causes the gun to rotate at the wrist. Reducing the rearward recoil force reduces muzzle rise. A compensator is excellent because it has a chamber where gas going forward slams into a "brick wall" causing a forward pointing force which cancels out part of the rearward pointing recoil force. Simple as that. Venting the gas up may have some minute effect but how much? To see, get some blank rounds and see how much recoil they have (almost none). Autos that fire blanks require gas restrictor orifices in the barrels just to generate enough rear force to move the slide.

A port has a very small forward offset effect because in turning the gas from going forward to upward, the gas exerts a forward pointing pressure on the barrel edge where it is deflected. I can imagine ports may do something, however in the ported barrels I have bought (four of them) the effect was so little it was insignificant.

Unless the barrel has some kind of forward expansion against a vertical face, IMHO the port's effect will be very small. Glaxco as I recall did some experiments with a compensator where he reduced the front face area and the effectiveness went away.
 
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Great thread--thanks for sharing your experiences--I've learned what I thought I knew ( if that makes any sense).

Steve
 
Here's my opinion (not just mine, learned from pro shooters). People confuse compensators with ports because both have ports directing gas upward. The myth is that the upward gas is the reason a compensator reduces recoil/muzzle lift. A good reference on this is contained in Glaxco's book "shooting from within". Muzzle rise is a result of recoil force which causes the gun to rotate at the wrist. Reducing the rearward recoil force reduces muzzle rise. A compensator is excellent because it has a chamber where gas going forward slams into a "brick wall" causing a forward pointing force which cancels out part of the rearward pointing recoil force. Simple as that. Venting the gas up may have some minute effect but how much? To see, get some blank rounds and see how much recoil they have (almost none). Autos that fire blanks require gas restrictor orifices in the barrels just to generate enough rear force to move the slide.

A port has a very small forward offset effect because in turning the gas from going forward to upward, the gas exerts a forward pointing pressure on the barrel edge where it is deflected. I can imagine ports may do something, however in the ported barrels I have bought (four of them) the effect was so little it was insignificant.

Unless the barrel has some kind of forward expansion against a vertical face, IMHO the port's effect will be very small. Glaxco as I recall did some experiments with a compensator where he reduced the front face area and the effectiveness went away.
That's Mike Plaxco's book, Bounty. I got to watch Mike shoot some back in 1992, when I shot the 3-Gun Nationals. I didn't get to squad with him, but was on the next squad, so we got to ogle the "Super Squad" a bit. Damn fine shooter, and his book is excellent.

You are correct about compensators versus mere ports. Even an expansion chamber makes a significant difference, as evidenced by my Quad Port 681s. What we learned back in the 80s was that gas volume is part of the key to compensator effectiveness. Some of our less efficient loads, using more powder, made our comps work better. Also, as regards "mere ports," the location and size of the ports matters.

The Hybrid porting system, pioneered by Schuemann, uses large, cone-shaped, vertical ports that begin pretty far back on the barrel. I have a little 642 Centennial done up by Jack Weigand with Hybrid porting, and it makes a huge difference in recoil and muzzle flip. Trouble is, it also reduces velocity by 50-100 fps., because so much gas is bled off so early. No free lunch.

With heavy bullet, large caliber loads, most of the recoil comes from the simple momentum of the bullet, and gas volume is relatively low. Therefore, porting doesn't do much. With light bullet, high pressure, high velocity loads, proportionately more of the recoil comes from the jet effect of the escaping powder gas ejecta, so redirecting the flow of gas makes a much bigger difference. In general, the more efficient a cartridge, the less good ports or a comp will do. That's why compensators work so well with cartridges like .300 WM and the Weatherbys, but not so much with .45-70s, .308s, etc. Can't escape Mother Physics.
 
That's Mike Plaxco's book, Bounty.
Sorry, with old age comes the kind of brain misfires where similar sounding words get mixed up. Glaxco is a company that makes pharmaceuticals which is another thing that comes with old age.....
 
With light bullet, high pressure, high velocity loads, proportionately more of the recoil comes from the jet effect of the escaping powder gas ejecta, so redirecting the flow of gas makes a much bigger difference.
Whic is what I thought, so I bought some ported barrels for some of my 9mm guns (shoots 115 gr). Browning HP, Beretta 92, SIG 226, Glock 34. I never felt any difference at all, so I guess 9mm is not a good choice for porting.
 
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