Just ordered the airforce Texan-mods started

"JohnL57"Holy crap! Nothing like jumping in at the deep end-how are you going to fill that beast? Lots of good info here, try doing a search.
And welcome!
John

hahaha I heard they were really good guns... I ordered an ac carbon fiber 88 cu in tank, some 110 grain hollow points and a  Hawke VANTAGE IR 4-12x50 AO Scope . 

should be a pretty nice starter pack. Looking for a good bipod and and red tactical light now.
 
Not sure I would choose the .308 for deer, but with a heavy bullet with a wide flat nose it should be ok. Shot placement trumps power with airguns. I assume you are near Fort Worth by your handle, there are a few airgunners around. We have field target clubs that shoot twice a month with small bores. The owner of Weatherford Pawn is a big Airforce Texan fan and makes a bunch of .45 bullets for them. I just talked to him about my Dragon Claw the other day and he has some .50 ammo in the works. Let me know if you want to shoot sometime....I may know a place. 
 
Came in a few days early!! First mod complete. Found an AR limb saver that fit perfectly over the metal bar. Front rail adapter and bipod should be in next week! Ready to try this bad boy out. 
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Texan valves are different as slug weight effects what your initial fill pressure should be for best accuracy. First fill to 3000 psi and shoot the slug and notice where your fill pressure is after first shot. For example say your gun is now down to 2700 psi after first shot. For best accuracy 2700 psi should always be your initial fill pressure with that weight slug. You should now have 3 good hunting shots. Nielsen of Nielsen Ammo told me of this method and my group size with the Texan got way tighter.