 
                     
                This is an AR lower that takes UMP magazines. I designed this a few years back and machined a few of them for customers of my gun shop. 
Enjoy!
 
                     
                    
                     
                SHIN KAIJU Jakl lower
 
                     
                TDB AR-15 LOWERS
 
                     
                ATA F3PD Mag Project
 
                     
                 
     
                            
                         
                            
                         
                            
                        