Ruger 22/45 magazine generations

[BobM]

I have two pre MkIII Ruger 22/45 pistols. Recently I decided I needed more magazines than I think I have. The “MkII” 22/45 mags seem difficult to find and I don’t think Ruger makes them anymore. I read on a rimfire forum that Mk III mags should work in the original generation 22/45. I bought two Mk III mags and took one and one of the pistols out today. The pistol would not run with the new mag but was fine with an old one.
I did find a site offering the MkII 22/45 mags so I have an order in but I was curious if anyone had any other experience or knowledge. I’ll try the other MkIII mag just in case the first one is defective.

[dtw]

Was this the first generation of the 22/45?

If so, I'm interested as well. Just put a red dot on mine, shooting it a lot more lately .

[awp_101]

I would check over at Rimfire Central (https://www.rimfirecentral.com/forums/) or Ruger Forum (https://www.rugerforum.com/). Mine are MKIV so I can't help...

[BobM]

Was this the first generation of the 22/45?

If so, I'm interested as well. Just put a red dot on mine, shooting it a lot more lately .

Yes, I found the receipt for it recently, I bought them new in 2002.

[BobM]

I would check over at Rimfire Central (https://www.rimfirecentral.com/forums/) or Ruger Forum (https://www.rugerforum.com/). Mine are MKIV so I can't help...

RF is where I read that the MkIII mag would work in the earlier guns.

[BobM]

I took the other MkIII mag out yesterday, it runs fine. I’ll call Ruger to see if I can exchange it.

I also found the MkII 22/45 mags in stock at Clark Custom so I bought five.