Ruger.22 pistol mag compatibility.

StevenH

Member

Joined: Jun 2007

Posts: 75307

EE: 100% (87)

USA

Posted: 1/8/2026 3:11:07 PM EDT

Do I have this right?

Mark4 22/45 magazines are backwards compatible with the Mark2 22/45.

But to use Mark2 22/45 mags in a Mark4 22/45 I need a Mark4 or aftermarket floor plate?

I’ve got a half dozen Mark2 22/45 mags and they feel and appear higher quality than the mags that came with my new Mark4 22/45.

Life member of CRPA. FPC contributor.

MikeSSS

Member

Joined: Dec 2004

Posts: 23866

EE: 0% (0)

TX, USA

Posted: 1/10/2026 2:35:23 AM EDT

[#1]

About earlier 22/45 mags in a MK IV 22/45:

Earlier 22/45 mags have a heel on the floor plate that prevents them from seating in a MK IV.

I carefully grind off that heel by using a bench grinder. Then the earlier mags work in the MK IV 22/45.

ALASKANFIRE

Member

Joined: Jul 2007

Posts: 50320

EE: 100% (5)

NV, USA

Posted: 1/10/2026 3:52:35 AM EDT

[#2]

MKII and III 22/45 interchange MKIV needs a different basepad or to be modded.

BikerNut:
Normal people like motorcycles. Real people like motorcycles.

People who don't like motorcycles are just... weird.

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Ruger.22 pistol mag compatibility.

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Ruger.22 pistol mag compatibility.

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Ruger.22 pistol mag compatibility.