4 barrel ports

[peterleduc]

I see the latest tech for air pistols is to have 4 very small barrel ports on the top of the barrel. Steyr, Walther & Benelli all have them but I'm not sure on the rest. Are they worth adding to a barrel? As a machinist and fiddler I'm capable, I just figured I'd see what the general opinion on this would be...

Regards,
Peter

[Rover]

If the guns have anti-recoil mechanisms, why would they need such things? (Not that I think they have any practical effect.)

MagnaPort would cut brakes into barrels using electrical discharge machining (EDM). This prevents burrs on the barrel interior. Are you prepared to do this?

[j-team]

I once ported a morini air pistol barrel for one of my clubmates.

He was trying to lessen the muzzle flip, I'm not sure that it really made much diffference. The Steyr style absorber type device does much more.

And, for what its worth I did use EDM to make the breakthrough to the bore (drilled most of the way to save time).

[peterleduc]

EDM porting is an option although I've never run the machine myself. I'll probably do the 85% drilling at home (on my Bridgport) and then take it down to the EDM for the finish. My guess is that if Steyr does it (even with their recoil mechanism) it has to make some difference.

Thanks for the tips guys.
Peter

[jbshooter]

Which walther has it?

[peterleduc]

From memory of what I've read, the LP400 has them, I could be wrong however.

Peter

[Gerard]

I'm not sure how much it does to reduce muzzle flip, but my Pardini K10 has 3 barrel ports and the exhaust a surprising volume of air. Laid a cloth across them and fired with a pellet loaded and watched the cloth jump up rather high. So I'd guess there might be considerable downwards force imparted to the muzzle end of the pistol by this upwards jetting. I'd also guess that the holes were drilled prior to cutting the rifling and any polishing of the bore, but could be guessing wrong there.

I worked in a machine shop for a year back in '89 and learned a fair bit, but obviously missed out on EDM. Never heard of it until now, but thanks, looking over some videos it looks very interesting for putting holes into hardened, finished objects and other uses. Here's a guy with a super-cute accent talking about results of his particular company's sloped-hole barrel porting in competitive shotguns:
http://www.youtube.com/watch?v=pt1_DUqjkXA

[william]

My old Pardini K2 had no ports. My new K2 has ports.

The difference in muzzle behavior that isn't directly related to my hold: nil.

The only real observed difference: my fellow shooters comment on how loud it is.

[Rover]

I've always felt that, while porting may actually reduce muzzle flip, it seems pointless as the pellet has already left the barrel.

With my own tests using a Walther CP3 and a Nygord Turbo-Comp on and off the gun, I would not bother.

[FredB]

I've always felt that, while porting may actually reduce muzzle flip, it seems pointless as the pellet has already left the barrel.

The pellet has already left the barrel before a muzzle-mounted compensator can act, but barrel porting can definitely act before the pellet is out of the barrel.

FredB

[Gerard]

Even before the pellet has reached the first port, the air being forced out ahead of the pellet is leaving through both muzzle and ports. So yeah, I think they're relevant. What seems lacking however is a quantifiable contribution to muzzle flip reduction with an average air pistol. Can't find anything like that. It'd take some sort of torque sensor mounted similarly to how a hand and wrist work, and testing on the same gun with a plain barrel and ported barrel otherwise identical.

[Rover]

If it makes the guy feel better, I guess he should go ahead and port the gun. Apparently, feeling good is the important thing.

[BEA]

Porting the barrel will likely do nothing other than change the way you feel about it. This being somewhat an experimental operation, my recommendation is to make sure you leave yourself with a plan B. The only viable plan B is to have the option of replacing this barrel with a new one should it get ruined in the maching operation.

[C. Perkins]

This is my two cents worth on compensators.
They were designed to aquire a rapid second shot or more.
Not for precision one shot at a time like we do.
Like said, the projectile has already left and down range before the full effect of the compensator is in play.
I do not see the point of this on a .22 or an air pistol.

Clarence

[j-team]

In many cases compensators (or muzzle brakes) can improve the accuracy of a firearm by directing the turbulent gas (or air) away from the projectile as it leaves the barrel. As its the gas (or air) that's pushing the projectile, it naturally wants to push past once the projectile leaves the barrel.

So, not all about recoil reduction.

[Rover]

I've heard that, but I have an old FWB2 with a "can't drop a pellet thru" test target. I doubt it gets better than that.