yes it uses the ruger 57 mags the 10 round mag is made so they can sell the gun in restricted states here is one with the 20 round mags budsgunshop.com/product_info.php/products_id/148651/ruger+lc+carbine+5.7x28mm+16.25+tb+20+1

Yes, same magazine as the Ruger 57. This model is sold with a 10 rounder for restricted states like mine unfortunately. Below is a link to the model that includes the 20 round magazine.
budsgunshop.com/product_info.php/products_id/148651/ruger+lc+carbine+5.7x28mm+16.25+tb+20+1

Hi Todd and welcome. This 10rd model is for sale in capacity restricted States. The 20rd standard model is available here : budsgunshop.com/product_info.php/products_id/148651/ruger+lc+carbine+5.7x28mm+16.25+tb+20+1 -------- Cheers, stay safe and enjoy. Spare magazines (2-Pack) if desired are available here : budsgunshop.com/product_info.php/products_id/120915/ruger+57+5.7+20rd+magazine+2pk

Hi Todd, yes this uses the same magazine as the Ruger 57. This model is sold with a 10rd magazines for those folks who live in restricted states, but it will also accept the 20rd magazine.
The model that comes with 20rd mag is here budsgunshop.com/product_info.php/products_id/148651/ruger+lc+carbine+5.7x28mm+16.25+tb+20+1 ,
Stay safe & have a great day!