Our replacement Colt Umarex 1911-22 Springs are truly an upgrade to the stock springs. The ZRTS springs are more durable than the factory ones. As seen in the picture below comparing the factory and ZRTS springs, the ZRTS springs utilize a thicker wire , which can help your pistol run smoother. Our improved recoil spring ensures reliability with bulk pack ammo and CCI MiniMags. These cure the issue of not returning to battery or sluggish cycling.