Here is an adapter made by Hi Calber to enable the Tirant45 to run a 3 lug for 45ACP, namely the APC45/APC45 Pro. You take the birdcage out of your Tirant45 and replace with these parts. You need to use the spring that is used with your piston booster assembly. $175 shipped. Venmo, Zelle or PayPal friends and family