Polygonal Barrel

[cruzans]

Question - I purchased my first pistol with a "polygonal barrel" a little while back ( CZ-82 ). I had heard the polygonal barrel gives great accuracy. I have to agree after shooting my CZ - incredibaly accurate. I have read that besides being more accurate, they tend to have less wear ( less of the surface of the bullet hits the sides? ). So my question is if they are so accurate, and a few other benefits, why do so few guns have them? Sorry if this is a dumb question, but I was thinking about it for a while.

[Asmodeus6]

Perhaps they cost more to make? And they can't be used with cast lead bullets. Well, they "can", but usually it's not recommended.

[toml]

Perhaps they cost more to make?

Yup. Notice that the Kahr PM9 has a polygonal barrel, but the 'economy version' CM9 has conventional rifling.

[cruzans]

I read about lead bullets not being recommended. But a couple comments I read said the polygonal was actually cheaper to produce - hmmm, have to keep reading I guess.

[chivvalry]

http://en.wikipedia.org/wiki/Polygonal_rifling

[SCBaldr]

I thought they were more expensive because they have to be forged around a mandrel that has the mirror image of the rifling cut into it. So in the forging process, the barrel has the polygonal rifling literally forged into it. That's what I understood.

[Tomcat088]

I thought they were more expensive because they have to be forged around a mandrel that has the mirror image of the rifling cut into it. So in the forging process, the barrel has the polygonal rifling literally forged into it. That's what I understood.

Polygonal rifling can be made lots of ways. The process of getting the polygonal rifling in the barrel doesn't just have to be from forging. You can also get polygonal rifling from button rifling, and cut rifling. There's also plenty of manufacturers that forge barrels with "normal" rifling. I honestly think you're putting a bit too much stock in the type of rifling, and how it relates to accuracy. It's just like the guys that always want "5R" rifling on rifles. It DOES have it's benefits, and does take a little bit more attention/time to get done correctly, but most people blow things like that way out of proportion. Most shooters don't shoot well enough to tell the difference in accuracy if there is one. They may get to enjoy the other benefits related to accuracy, cleaning, etc. I honestly think the reason that they shoot well is because they're nice firearms with lots of quality control checks, good materials, and attention to detail. It wouldn't matter if their barrel had radiused, polygonal, traditional, hexagonal, or differences in number of grooves. They're professionals that pay attention to their work and don't settle or anything except quality. I think the bottom line is with guys that pay close attention to quality, the firearm is going to shoot and shoot accurately. With rifle barrels you see makers with 6 grooves, 5 grooves, 4, 3, etc, etc. Guys that know what they're doing can make any of them shoot, and with a good finish, can make them easy to clean. Don't get caught up in the silly stuff that's people are usually just using to sell. Pay attention to the quality and the end results (good accuracy, more velocity, easier to clean, etc).

[SCBaldr]

Good to know thanks.
I just thought that it had to be forged in, didn't know that it could be machined or cut in. I'm not trying to get hung up on this v. that. I just thought it had narrower definition.

[offshorebear]

The accuracy of a 3.8" barreled pistol is almost all in the hands of the shooter, not the gun.

Polygonal rifling creates a better seal with the bullet and thus increased velocities. I'm sure there are other benefits and compromises.

[mrnyman]

Alot of American Guns do not have it because its not an American invention, Americans do not like to follow other technologies, though we did for example : the automobile, the zipper, the helicopter, penicilin, the locomotive.

Back to the Poly Rifling, even before WW1 the Germans use it in Artillery pieces and in WW2 both the MG34 and 42 used it, so it were not meant to fire non-jacketed rounds .