Velocity loss with ported barrels?

TruthTellers

New member
Asking in regards to a .357 Mag revolver, but figure that this question applies to pistols as well. I'm wondering how much velocity is generally lost with a ported barrel?
 
I believe Glock indicates about a 30 fps loss in their 9mm ported guns.

The article below found a larger difference in speed between a ported and non-ported 9mm Glock barrel, but recognized that they were two different barrels.

https://gundigest.com/article/ported-barrel-reduce-recoil

"The ported barrel produced less velocity than the non-ported barrel. The 115-grain load was 78 fps slower, the 124- and 147-grain loads were 55 fps and 53 fps slower, respectively."
 
I used the same ammo before and after but I wasn't necessarily doing so for chrony purposes. a co-worker handloads and used a chrony so when I happened to with him I shot across it too just because. I used wwb 110gr. jhp and rem 125gr. sjhp.
 
In articles and tests I've read it's not so much as some people might think. Certainly not enough to make a difference to anything you may want to shoot.

It will vary on the length of barrel, type of ammo, bullet and type powder used by the handloader or manufacturer.

Looks like the figures given already are about right with what I've read.

Here's a link from this forum

https://thefiringline.com/forums/showthread.php?t=465655

tipoc
 
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Here is an article from the U.S. Concealed Carry Association that involved shooting two Ruger SP101s. One ported and one not. Looks to be a 3" barrel.

https://www.usconcealedcarry.com/blog/gun-porting-defensive-handgun-port/

He reports about 100 pfs with a 110 gr. bullet.

This is quite a bit till you note the type porting that was done. Holes were drilled down most of the length of the barrel. Magnaport does an entirely different type porting that results in less of a loss.

http://www.magnaport.com/hgun.html

tipoc
 
Comparing 2 different guns is useless information. There can be 50-100 fps difference between 2 seemingly identical guns.
 
Yep so what you get is a general idea.

That's about all you ever get. But folks know that, or should.

tipoc
 
I have a Glock 23, 23c and 27 - a generalization would be the 23c produces velocity comparable to the 27 (about 50-60 fps loss).
 
I’ve got a Smith Model 66 F Comp. Factory ported. It has the big expansion chamber port. I just kind of think of it as a 2 /2” barrel.

Shooting it at a covered range one day, every shot knocked dirt off the overhead baffles. So, energy was definitely going up.
 
One thing is certain: The ported barrel won't be faster (assuming a statistically relevant sample of ammo)
 
One thing is certain: The ported barrel won't be faster (assuming a statistically relevant sample of ammo)

Never? Well, hardly ever.
There is such a thing as a "fast barrel" and you might get a fast ported barrel and a slow straight barrel.
 
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