I honestly don't know, but I use MecGar 17rnd mags, they fit flush and are actually the same manufacturer as the factory mags, just without the SIG logo. They also cost about $25 as opposed to about $40 for the official factory mags. In Limited, if you're shooting a 9mm you'll be scored minor, meaning all your A hits will still be 5 points but your B hits will be 3 instead of 4, Cs 2 instead of 3, Ds, 1 instead of 2. You may want to shoot Production instead, there's a 10 round mag limit, but everyone's scored minor and 99.9% of shooters shoot 9mm. I shoot my 226 in Limited for fun if I have time after I shoot my Wilson L-10 gun, and just offset the minor scoring with higher capacity and greater accuracy. My buddy does the same thing with his CZ-75 in 9mm. After he frustrates himself with his constantly shifting sight on his Para he makes himself feel better by beating half the Limited shooters with the CZ.