Which 9mms have polygonal bores?

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wbond

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Which 9mms have polygonal bores? I like polygonal bores.

I know that Glock and Kahr do. What others?

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Note: My original message was the above.

Due to various questions and comments, I'm adding a little more detail below to explain my interest:

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Polygonal bores allegedly give about 40 fps more velocity from same ammo than land and groove. That's important for my anemic 9x18s. The CZ-83 9x18 has chrome plated polygonal bore. Nice.

As for accuracy, I'm not sure that matters. However, I can say my CZ-83 9x18 is amazingly accurate, even at distances you'd never think of using that small a gun at. My CZ-83 9x18 is my only polygonal and it's also my most accurate gun. Coincidence? Don't know.

Polygonal bores last longer too. That's an accepted fact. The greater velocity is considered accepted fact by some and rumor by others. I don't know for sure about the velocity claims. As for accuracy, I don't know if it's more accurate, but I know mine is very accurate.

Lastly, I also like chrome plated bores. Since polygonal bores have less surface area (i.e. - they're smoother) they are easier to chrome plate. There is nothing nicer than a chrome plated polygonal bore, in my opinion. A stainless steel polygonal poor would be nicer yet, but I don't know if that exists.

My CZ-83 9x18 is both polygonal and chrome plated. I love it. The chrome plating makes it very easy to see if it's dirty and prevents rust (wet climate).

Since my CZ-83 9x18 polygonal is my favorite, I figure I'd like to try a 9mm Para with polygonal.

Anyone know which 9mm Para polygonal bore guns are chrome plated-lined inside? Are there any stainless steel polygonal bore guns?
 
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Lookin' down the bore of a Beretta PX4 and it looks polygonal to me. Gonna have to check the official specs.

Glocks are, too, aren't they?
 
The ONLY czech-made CZs with polygonal barrels are the CZ-83s (and then only in 9x18, I think) which aren't being imported, right now. None of the 9mm CZ have ever used polygonal barrels, that I'm aware of -- even the CZ-100.

There are several guns with "CZ" in their names (made in Italy, made in Yugoslavia, etc. Some of them might have done polygonal barrels, but I don't think so.)

Some of the Magnum Research Baby Eagle guns did do polygonal during the late 90's, but they now seem to be using conventional land/groove barrels.

Glock and H&K are the main one, now.

Most folks, including handloaders, prefer to avoid polygonal barrels.
 
My CZ-75 compact has a polygonal bore and is very accurate. The CZ-82 in 9x18 also has a polygonal bore and is being imported and sold at s.o.g.
 
DISCLAIMER...I'm about to sound like an idiot.

What's the difference between teh polygonal and conventional type?
 
From Wikipedia (http://en.wikipedia.org/wiki/Polygonal_rifling):

Polygonal rifling is a relatively new type of rifling wherein the traditional lands and grooves are replaced instead by "hills and valleys" in a polygonal pattern, usually a hexagon. This has many advantages over the traditional form of rifling, in that it deforms the bullet less while also sealing the gas slightly better, resulting in a slightly higher muzzle velocity in most cases. Because the bullet is less deformed, it provides less surface area for the wind to push against and thus it is more accurate at long range. Also, as a result of the fewer sharp edges pushing against the bullet, the barrel life is extended compared to that of a traditionally rifled barrel.

This type of rifling, however, has drawn criticism from various law enforcement agencies because, unlike the deformations traditional rifling leave on a bullet, deformations left on a bullet by polygonal rifling cannot be used to identify which gun fired the round. As a result, many of these agencies forbid the use of polygonal rifling so that shots fired by the officers may be identified as such.

Another disadvantage to polygonal rifling is that firing lead bullets through the barrel results in an accumulation of lead — a phenomenon known as "leading", that can lead to poor accuracy or even barrel failure.

The most notable manufacturer to create barrels with polygonal rifling is GLOCK, though there are others that manufacture them as well, such as Kahr arms and Heckler and Koch.
 
I do not understand why a firearm manufacturer would use polygonal rifling as opposed to conventional. If Barsto can produce a conventionally rifled and fully supported chamber barrel for Glocks, then Glock should also, if for no other reason than civil liability.
 
As I understand it -- but this may be incorrect -- polygonal barrels are very effective for a given diameter, but are less expensive to manufacture. Then too, the vast majority of handgun shooters buying new service pistols probably DON'T shoot lead. So a lower-cost alternative which does not suffer performance degradation, is arguably a good business decision.

One acquaintance, a master level (professional) shooter uses lead in his Glocks -- losts of rounds -- without problems. He says the secret is sizing the bullet to the barrel, as some barrels have overlarge dimensions -- and that extra space allows more hot gases to hit the lead and that causes leading.
 
Seven High said:
I do not understand why a firearm manufacturer would use polygonal rifling as opposed to conventional. If Barsto can produce a conventionally rifled and fully supported chamber barrel for Glocks, then Glock should also, if for no other reason than civil liability.
Click to expand...

I don't understand how a design that is almost a century old, still have problems either. :rolleyes: After several manufacturers trying to improve it, you would think by now they would have worked out the kinks! What's up with that?

This glock unsupported chamber is much ado about nothing perpetuated by certain individual for his own interest. How come my Glock 22 didn't blow up on me? Explain this!

Back to original topic, All my HK's have polybore, including my new P2000.
 
Candr44 wrote:
My CZ-75 compact has a polygonal bore and is very accurate. The CZ-82 in 9x18 also has a polygonal bore and is being imported and sold at s.o.g.
Click to expand...
You have a truly unique CZ-75 Compact.

I've had several Compacts and have one now. None of the ones I've seen (or ever heard of) had a polygonal barrel. Be sure to let CZ know about it.

I've been a moderator on the CZ-Forum (5400+ member as of today) for a number of years, now, and we have many "Compact" owners on the CZ Forum -- but yours will be the first one anyone has encountered or mentioned. It might have some collector value if its a "factory-made" barrel; its certainly unusual.

(The CZ-82, on the other hand, is essentially the same gun as the CZ-83, created for military use. The 83 is the only polygonal I've encountered, but it makes sense that there are 82s made the same way -- '82 being the year of introduction.)
 
The better velocity thing

not sure that's really true. I've heard it said before.

CZ barrels are hammer forged, but they are not polygonal (from what I've seen).

I suspect Steyr might use polygonal rifling.
 
As I understand it, all GLOCKs, and HK USPs after November '94 do. The manufacturers pitch it as a high-tech barrel-rifling technique that seals the gases behind the bullet in the barrel more fully and produces higher velocities and better accuracy in a given barrel length than conventional rifling. Their detractors claim it is cost-saving measure. I suppose there may be a grain of truth to both positions. I recall that when I bought my USP (I was pretty technically ignorant at the time - probably still am, but improving), I thought, "Wow...polygonal rifling. This is the pistol of the future. To the hovercar!" :D Needless to say, I had no real idea of the difference, and I still don't know if the claims of "better seal", etc., are true, or what kind of savings there are from manufacturing barrels with polygonal rifling.

From a practical perspective, lead bullets are generally not recommended in polygonally-rifled barrels due to accelerated lead build-up and potential resultant overpressure problems. As for myself, I find them quicker to scrub clean than the conventionally-rifled barrel in my 1911, although that may have nothing to do with the rifling. :)
 
Walt, my CZ-75 compact is original. the barrel is stamped with the same serial number as the frame [ #D88xx] and it is definately polygonal. It is a dual tone that I bought from a retired fl. state trooper. It was obviously carried alot but not fired much.
 
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