【CUSTOM GBB WORKSHOP】 COLT AMALITE AR-15 model 601 rifle ghk base deep marking, deep 0.3mm custom upper kit 7075-t6 forged for ghk V2 custom steel out barrel custom steel flash hider custom handguard custom stock custom grip custom bolt chrome real front rear swivel real rear front sight real trigger guard real charging handle real cover plate real magazine catch real front pivot pin cerakote Anodizing phosphate coating detail fix