The K9 weights 23.1 ounces.
The PM9 weights 14 ounces.
I bought an early stainless K9 and it's never even acted like it would jam.
It's accurate, reliable, and one of the safest small autos to carry due to the revolver-like trigger.
In fact, I tell people to shoot the Kahr's like they're revolvers.
If you've never handled a DA revolver much there may be a learning curve as you learn to shoot DA, but if you've spent any time with a revolver you'll be right at home.
I prefer the all steel model over the polymer, and Kahr seems to have had the least trouble with the steel models.
For ammo, since every gun is an individual recommendations are of little value. Just buy a brand of premium American made defense 9mm ammo and test it. If it works reliably, you're done.
There is NO "Best" defense ammo. The premium brands are so close together in effectiveness that it's a waste playing around looking for "the best".
Remember, the most important thing with a defense gun is reliability. Not accuracy, not looks, not even caliber.
Since your Kahr is used, you'd be smart to buy a new recoil spring. These small guns are hard on springs and unless you know for sure how many rounds have been through it the spring may be due for replacement.
The Kahr web site has a wide selection of top quality Kahr comparable holsters.
https://shopkahrfirearmsgroup.com/
Here's my early K9 stainless.
It really didn't need it but I did some edge reduction and stippled the front strap and the under side of the tang.
This was the first auto pistol I saw that was this smooth inside. There were no burrs that needed removing, and no polishing or smoothing of parts was needed.
Prices are high but how much is your life worth?
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I build my own holsters. Here's a cross draw with a sight protecting front seam and a Half-and Half rear seam.
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