Are KAHR 9mm and 40S&W mags same size dimensionally?

[pk1313]

Just wondering if the 9mm and 40S&W mags are the same size dimensionally on the outside? Can anybody with calipers actually confirm yes or no. Thanks,

[wyntrout]

I haven't measured them, but I've worked with both and found that they are NOT interchangeable. 9mm is too loose in the .40 mags and the .40's too tight in the 9mm mags. The metal base plates are interchangeable and I replaced the plastic ones on the standard mags with the metal ones for less bulk in CCW. The followers are different, too. The springs are the same, I believe.
I tried "stretching" the metal tubes of the 9mm mags to take .40 rounds, but that wasn't worthwhile... wasted time and frustrating.

[pk1313]

I was just messing around Frankensteining some Kahr's together. I have Tanfoglio's for my competition guns - a full size Limited for USPSA and a Witness Match for IDPA but I have uppers in 45ACP,40S&W,9mm and 22lr that will swap on both frames. All the magazines are the same dimension on the outside with just the feed lips being different. I was just wondering if I could top my K40 Covert with a K9 slide and 9mm mag and shoot away. I'll post a pic later of my K9 with a T9 top.

[gb6491]

My caliper eludes me just now, but there is some difference in dimensions between the 9 and 40 mags. I have my PM9 and P40 Covert handy and the 40 mag will fit into the PM9 but it is a tighter fit than the 9 mag. The 40 mag has to be pulled out; the 9 will drop free.

My experience with rounds fitting into the different mags also varies from Wynn's as I've found (and just checked again) that 9 and 40 will fit in either mags. Years ago I had a CM9 that I converted to a PM40 with a top end that I found on an auction site. That gun fired 40 just fine with the CM9 mags:

https://www.youtube.com/watch?v=Re3HK45iEBk

As Wynn has had different results from mine, it's likely the above results are dependent upon the individual guns and mags involved. YMMV:w00t:

Regards,
Greg

[pk1313]

Thanks Greg - I was just trying to keep a gun I frankenstein from blowing up in my face - LOL!! I'm glad yours worked great !!! It must me nice to just go out anywhere in the desert and just blast away - there are NO places to shoot anywhere in SW FL near Fort Myers / Sanibel Captiva unless you drive an hour or so -- other than that it is public ranges or indoor ranges.

[Bawanna]

Good to see a Greg post, kind of miss em. I too envy his shooting ranges. Plenty of open area around me in the NW here but few places to shoot without that long drive. Even the closest indoor ranges are 45-1 hour away.

[GROTMAN]

good to see a greg post, kind of miss em. I too envy his shooting ranges. Plenty of open area around me in the nw here but few places to shoot without that long drive. Even the closest indoor ranges are 45-1 hour away.

me too. When i dont see a regular post in awhile start to wonder if something happened to them. Been afraid to ask. Glad to see you are still doing well greg!