Kkm Twist Rate

[unclez]

Just got my KKM barrel today for my G34 and noticed the twist rate in the KKM is a lot slower than the factory barrel. Anybody know what the exact twist rate is? And why they went to such a vast difference?

[Joe D]

They must have "tuned" their twist rate to match a lighter bullet. This might be an issue with heavy bullets. Guess that's why I tend to stick with the stock barrels. Never found a reason to buy an aftermarket barrel for a Glock.

Every Glock I own will group better than 1 1/2" at 25 yds. My wife's G34 goes way under 1" with a 147 gr bullet.

Edited September 23, 2006 by Joe D

[Micah]

Guess that's why I tend to stick with the stock barrels. Never found a reason to buy an aftermarket barrel for a Glock.

+1

I searched for about 25 minutes to figure out the twist rate...the only thing that I came up with was for a 10mm

[SRT Driver]

1:16

[unclez]

1:16

Thanks SRT. Now would you happen to know why they went with such a slower twist than the factory 1:10 and if indeed anyone has had trouble stablizing a heavier bullet (147) in the slower twist?

Edited September 24, 2006 by unclez

[L9X25]

1:16 is pretty much standard with the 1911 crowd for slower projectiles

Edited September 24, 2006 by L9X25

[SRT Driver]

1:16 is pretty much standard with the 1911 crowd for slower projectiles

+1 I'd bet that the reason for the 16 twist is standardization. Not aware of any mgfr that makes an aftermarket Glock bbl in 1:9 or 1:10 twist.

147's out of a G34 with a KKM shoot fine.

But so do 115's and 125's. Was there a difference? Not really, besides the cost of the 147's. Never had a problem with steel at 135 or so PF either with the 125's.

[Wayne Dobbs]

The 1:16 twist rate is easier on cast bullets also, allowing them to engage the rifling with less chance of skidding in the transition from the throat to the bore. Smith and Wesson used that twist rate for years in their 9mm service pistols, although I don't know if they still do.

JoeD: Can you tell us what load you're using with that 147 grain bullet that's grouping so well, please?

Wayne

[Flexmoney]

JoeD: Can you tell us what load you're using with that 147 grain bullet that's grouping so well, please?

Wayne, a quick search using JoeD's unsername and "147"...showing results as "posts" pulls this up: http://www.brianenos.com/forums/index.php?...mp;highlite=147

He states his load quite a few times in various posts. (3.0g of TG with Rainer 147's)

Some good reading.

[Joe D]

I had to think back on the time frame when I shot that tiny group. At that time we were using West Coast bullets. I stated incorrectly that I used Rainier. West Cost at one time would ship bullets freight free. Seems like we had to order 20,000-30,000 to get the free shipping.

Yes, the load is 3.0 gr of Titegroup. One thing I have noticed is my G35s and her G34 seems to shoot anyone's plated bullets very accurately. We are currently using Berry Bullets. They appear to have the best price.