Texan Airgun making 900 ft lbs energy

My modified .45 Airforce Texan airgun making 900 fpe. Custom built Doug Noble Valve supplying the power. Started first day with lighter bullets and hit 881 fpe. 10 days later with heavier mold I drilled nose to get the right weight at max pressure to achieve this. Heavier weight and energy will start falling off. For other LONG RANGE VIDEO of my Texan    • TEXAN .45 AIRGUN LONG RANGE   To 1108 yds with my .257    • .257 Air Rifle Long Range      / verybigrifle