Fixing inaccuracy in my CW9

[Steve in Sunny Fla]

My CW9 has ALWAYS shot low left, badly. Like 7" low and about 3" right at 10 yards. Not me, I can keep all shots in a 3" bull with my K9 and could do it easily with my CW40. After almost 1K rounds from the CW9, I decided it was time to fix it. I ended up having a tiny dot of stainless welded onto the barrel where the ring is just ahead of the barrel hood. I filed it down to be .015" higher than it was from Kahr. Imagine that, all in the bull at 10 yards. In careful measuring, the hood is down the exact same amount from the slide when in battery as my K9 is. HMMM, Kahr messed this one up, which I think maybe somewhat common on the "value priced" CW line. I can say with absolute certainty it isn't always the shooter... Steve

[Decado]

So, that tightened up the barrel lockup?

[Steve in Sunny Fla]

No, it lowered the back of the barrel, so that it isn't hitting low anymore. Steve

[Steve in Sunny Fla]

Shot another 75 rounds today, I'm glad to say that the accuracy issue is absolutely fixed. It really took a long time for me to be sure it was the gun and not me, especially since any threads about inaccuracy are generally met with "it's you, not the gun" responses. I'm here to tell y'all, sometimes it really IS the gun. Steve

[CJB]

Sorry. I gotta call BS on this.

I love ya Steve, but the math does not hold up.

To be off by 7 inches at 10 yards, your barrel would be damn near .060 out of kilter.

That, folks, is 1/16 of an inch - thereabouts.

The barrel was not off by that amount. It just wasn't. You said .015 - I don't doubt your benefit, but the amount you'd correct with that sort of re-alignment would only be just short of two inches at 10 yards.

Sorry - it was you.

Then there's always the little item of firing pin strikes on the primer.... didn't even wanna go there....

[jocko]

u had to have a bad barrel, why not just send it back to kahr and let them doit right. One thing is for certain, u can kiss ur barrel warranty good by and maybe even the rest of the gun. If u happy that is all that matters. I am not an engineer in no way shape or forum 98% of the time it is indeed shooter error but we have seen replacements of barrels, and slides even. I seriously doubt in anyway that kahr puts in sub prme parts in the cw or cm series. that I just do not buy.

glad u fixed it to ur acceptance. When u put a torch to a kahr, u best know exactly what ur doin to...

[CJB]

Should say...

The math for a three inch barrel at 10 yards.

Ten yards = 30 feet = 360 inches.

We have a 1:120 ratio of barrel to target

1/120th of 7 inches... .058xyz inches.

That could be a combination of front and back being offset, doesn't have to be all at one end.

BTW, doing the same math on sight radius is gonna get you close to the gnats rosette every time.

[Steve in Sunny Fla]

As far as warranty, here's my opinion on that. I had a cw40 that was uber accurate, but couldn't go through 100 rounds without a failure. back to kahr twice, and still acting up. when i got the cw9 it ran, and has always run flawlessly. Reliability is of higher priority than accuracy in a carry weapon, and the LAST thing I wanted was to send the gun back and maybe risk getting an accurate but finicky weapon. Besides, I'd already done the covert cut on the frame, so it's MY gun. I understand that. I made my choices, and don't regret them.

CJB - Now back to the math. your math is good, but you didn't consider one thing. I didn't move the FRONT of the barrel .015", I moved the BACK, virtually at the bullet. Given a 3" distance from there to the front of the barrel, it WOULD translate to a change of .045" (.015" x 3") at the front and .015" at the back. Total, .060" and which is getting alot closer to your figure of .058xx.
Being that you're in Fl, you're more than welcome to shoot it and see what you think ... Steve

[AlbinLee]

My CW9 could shoot the **** off a fly. That thing is POA/POI, with minor vertical POI variations by hand-loads of different bullet grain (intentional).

[Steve in Sunny Fla]

My CW9 could shoot the **** off a fly. That thing is POA/POI, with minor vertical POI variations by hand-loads of different bullet grain (intentional).


Mine is now!

CJB - haven't heard your opinion on my math... I used your formula... Still calling BS? :53: Steve

[CJB]

As far as warranty, here's my opinion on that. I had a cw40 that was uber accurate, but couldn't go through 100 rounds without a failure. back to kahr twice, and still acting up. when i got the cw9 it ran, and has always run flawlessly. Reliability is of higher priority than accuracy in a carry weapon, and the LAST thing I wanted was to send the gun back and maybe risk getting an accurate but finicky weapon. Besides, I'd already done the covert cut on the frame, so it's MY gun. I understand that. I made my choices, and don't regret them.

CJB - Now back to the math. your math is good, but you didn't consider one thing. I didn't move the FRONT of the barrel .015", I moved the BACK, virtually at the bullet. Given a 3" distance from there to the front of the barrel, it WOULD translate to a change of .045" (.015" x 3") at the front and .015" at the back. Total, .060" and which is getting alot closer to your figure of .058xx.
Being that you're in Fl, you're more than welcome to shoot it and see what you think ... Steve

Moving the front or back is not "exactly" the same, but you end up with something like the difference between 120:1 ratio, and 119:1 ratio - so the difference is effectively nil.

In all practical terms, you can use the same math for the front and rear sight... or barrel... and my calculation was for the rear moving (out of habit I guess).

[Steve in Sunny Fla]

Sorry, Impossible. The new centerline moves away as a multiplication of the distance, which is exactly the formula you previously quoted. The bullet centerline was dropped .015"at the bullet. At the front of the 3" barrel, that's a change of .045" of the centerline. .060" difference in the barrel centerline from previous POI.

Here's another way to look at it
.060" change in centerline for 3"barrel x4"= .240" change per foot.
.240" x 30 Ft = 7.200" change to POI.
Simple math.
Steve

[CJB]

I'm not gonna argue with you over this... <click>

[mr surveyor]

I'd like to see a post in the next couple of weeks where you two guys got together at the range and checked this deal out. I have no doubt this particular gun was an anomoly out of the box, and that it was remedied with a bit of daring ingenuity, but still not the norm for a CW9. My cw9 and every other copy I've personally known of has been as accurate/precise a shooter out of the box as any wonder nine on the market, and every bit as reliable as any.

Since the gun had been "customized", I can see the apprehension concerning sending it back for factory warranty, and the DIY approach was the best remedy. But, I would have sent an obviously faulty product back to be corrected before making any permanent personalized changes to the platform.


surv