Sig Sauer builds this factory magazine (part no. MAG-229-43-12) for the P229, holding 12 rounds in a black phosphate steel body sized for both .40 S&W and .357 SIG, two cartridges that share the same case dimensions and magazine geometry. That shared fit means P229 owners can switch barrels between the two chamberings without needing separate magazines. Manufactured to Sig’s own factory tolerances, it feeds and seats exactly as the P229 was engineered to run. For Sig Sauer P229 owners, this handgun magazine is a dependable factory-correct spare.

Key Specifications

• Chambered for .40 S&W and .357 SIG, sharing one magazine geometry.
• Holds 12 rounds, the standard capacity for this platform.
• Fits the Sig Sauer P229 as a factory-spec magazine.
• Finished in black phosphate steel for a durable, low-glare surface.

Frequently Asked Questions

Does one magazine work for both .40 S&W and .357 SIG? Yes, both cartridges share the same case head dimensions and run through this same magazine.

Is this a genuine Sig Sauer factory magazine? Yes, manufactured by Sig Sauer to P229 specifications.

Buy the Sig Sauer P229 12-Round .40 S&W/.357 SIG Magazine

A factory-correct spare keeps a P229 running reliably in either chambering. Order it from our Lubbock, Texas gun shop for fast, insured shipping.