Technical answer required - Effects of Porting on a bullet?

[KCDUDE]

On a short barrel 1.5" to 2" NAA revolver, what are the effects does a ported barrel have on the velocity and performance a bullet?

What is the best ammo to be used in these short barrel revolvers?

[theysayimnotme]

I doubt it is much but that is only a guess. The value of porting is also probably very little due to the short moment arm. I had a compensator on a .22 short Hi-Standard Olympic pistol but that had a much longer barrel & larger porting.

[Canoeal]

Since gas escapes behind the projectile, and so pressure would have to drop, I would have to believe it would have the same effect as shortening the barrel to where the ports are. JMHO.

[grayelky]

It has been many years since I have read up on porting. Back in it's infancy, there were hundreds of theories about loss of velocity, loss of accuracy, etc. I read an article where a (I think) 357 magnum was toasted with several brands of HP ammo for accuracy and velocity. The gun was then taken to Mag-Na-Port and ported. It was once again teased for accuracy and velocity loss. The differences were about what you would expect as variances from one lot of ammo to the next. The accuracy was essentially the same. There was a very slight loss in velocity, but it was very minor. Statistically not important. With the differences in equipment available today, I would like to see this test re-run to see if the better equipment can see any more difference than what was detectable back in the dark ages.

As to the NAA magnums. I have a ported and a non-ported 1 1/8" magnum. If you shoot them back to back, you can tell a slight difference in muzzle rise, or flip. However, if you were to shoot one today, come back tomorrow and shoot the other, you would likely say there is no difference.

KC DUDE-
You asked about which ammo is the best. That is about like asking is Ford or Chevy better? Which is the best oil for my m/c? You can almost get a fight started with those questions. I prefer either Hornady Critical Defense, or Speer Gold Dot. Both of these are designed for short barreled 22 mag revolvers, and produce notably less muzzle flash than any ammo designed for a rifle. Several on here have done chronograph testing, and have found var it ammo with lighter bullets that produces higher velocity. No argument, but I will stick with the Hornady Critical Defense and its 45 grain bullet over the 30 grain varmint bullets. I suggest you do your own testing and see what your gun likes and what you like based on its performance. Good luck, and, if you any testing, please let us know what you find out, and what you decide.

[KCDUDE]

Per FBI penetration tests done and tabulated using a NAA short barrel 22 LR, the HANDS DOWN best ammo was the CCI Mini MAG 22 LR Copper - Plated Hollow Point consistently got at least 11" and some 12" penetration.  See Ammo Quest You Tube video and the tabulated testing at:
Http://shootingthe bull.net/blog/naa-2
There was no hollow point expansion observed.

[Dinadan]

KC - there is often a trade off between bullet penetration and bullet expansion. A bullet that expands or fragments will probably leave a bigger wound. A bullet that does not expand might penetrate deeper. Please understand that millions of words have been written on the internet, some them here, debating which is best.


By the way, regarding your question about best ammo, that will depend on whether you are looking for LR or Mags.

[Wumbey Goomba]

The best ammo, is the ammo that's
in your firearm, when you need it.
As long as it's with you. Nuff said.

[Boisesteve]

I'm an experiment of one, but when I did my chrono testing the only rimfire ammo brand that had zero failures-to-fire for me in my NAA was CCI, so that's what I stick with. Good priming... or maybe it was randomness, but I carry CCI.

[Canoeal]

Your ammo, for your liking, is going to be a compromise, no matter what ammo or small caliber you use. If you want deeper penetration you will give up expansion. If you want expansion the projectile will stop quicker lessening the penetration. You need to decide for you what is acceptable. I chose to have some expansion, and reasonable penetration. TNT style bullets do expand out of a mouse gun, but penetration is severely lacking; FMJ will penetrate but leave is .22 caliber hole.

I expect better is to be had, and find that the short barrel ammo works the best. I choose Gold Dots as the expansion seems to be more consistent and it always seems to fire for me. Hornady CD is my second choice, and beyond that I won't need to go.

I may use some other ammo at the range as I also use CCI Gamepoints, and Fiocchi 40 gr in my Henry. I used to use CCI hp+v 30 grains at the range but I have since found they end up with a different POA. Just the way I overthink things.

The attached chart from an article on .22 mags is what started me thinking...the 1" barrel is a beloved Pug.

[Canoeal]

This one might tally the same way for other calibers...

https://www.luckygunner.com/labs/pocket-pistol-caliber-gel-test-results/?