Hi Eric, yes sir, 10rd Mec-Gar mags will sit flush, as they are the same dimension as the 9rd mags.
Stay safe & have a great day!

Will sit flush to the m-base.

These 10 round mec gar magazines will be flush fitting since the are the same size as the OEM 9 round magazines.

Will sit flush to the magwell base.

Hi Eric and welcome. The 10rd Mec-Gar Magazines are the same overall length as the standard 9rd magazines and will fit flush. Cheers, stay safe and enjoy!

Good afternoon to you!! The mec gar magazine should fit flush. Hope this helps. Have a good rest of your day.
🇺🇸🇺🇸 'Merica' 🇺🇸🇺🇸