What is the OAL of your rifle? I have one of these coming: https://www.budsgunshop.com/catalog/product_info.php/products_id/714017770/ALLEN+COMBAT+TAC+RIFLE+CS+42+BLK
It is 42" long and will accommodate an optic. I too bought it just to have something to carry my rifle to the state-run rifle range that insists on having all rifles cased, and also insists on several seconds between shots.