Old style recoil assembly vs new style assembly

[drw]

What is the difference in the Old vs New style recoil assembly for the PM9 and PM40? Is the MK40 a old style recoil assembly???

[Ed M]

There's a type 1, type 2, and type 3 recoil assembly for the PM series. The 9 and 40 caliber are the same assemblies.

There are 2 types of slides for the PM series. One is the older blunt nose style, and the other is the new style with a taper on the front. Sorta looks like the CM slide up front.

The old style slides take a 13 coil outer spring. The new (slightly longer) slides take a 15 coil spring.

Kahr sent me a 15 coil spring with my Type 1 recoil assembly, and it worked awful until I cut 2 coils off the spring. Slide wouldn't lock back at all with the long spring.

The type 1 & 2 recoil assemblies differ in the size of the rear flange (3/8" vs 1/2").

PM recoil assemblies use an uncaptured outer recoil spring. MK recoil assemblies use a captured outer spring. Different system, and NOT interchangeable with PM assemblies.

Here's a picture of the 3 types of PM assemblies, but it's tiny, and tough to see....

[JethrosDad]

Very Informative post Ed. I looked for a while for this information when I found a P9 slide and barrel on gunbroker. I almost bought it to put on my CW9 frame but after digging on the forum a while found it was the old flat nose type and used different recoil spring assembly.

Again very nice to have this info on the forum. Thank you!

[Bawanna]

You'd just have to shorten the spring a coil or two and it would work. As I recall it's just long enough it won't work without shortening tiny bit.

[hasselhoss]

Any ideas why they changed the assemblies? I have a PM9 with the shorter slide and a new CM9 Tungsten. The difference in trigger pull and ease of slide tracking is very noticeable between the two with the older style feeling much better to me. Do the new pM9s feel better than their CM counterparts?