I finally achived some accuracy with slugs and Airforce Condor.. I took the factory Airforce lother wather barrel with choke at 18 inchs and cut 1 inch off the muzzle end.. I hand lead lapped the barrel.. Its .221 in diameter... I got a mold from a .225 48 grain bowman mold decked down to a weight of now 39.0 grains.. To my suprise in testing the slugs unsized at .225 shoot best.. Im using a Doug Noble valve and heavy spring and 110 gram hammer .. Its accurate and right at 1050-1065fps... I wasnt expecting good results...I figured it wouldnt stablise in the 1-17.7 twist..I was wrong...The Lother walther barrel looks really good in the borescope..The best interior finish i have in a barrel currently... I thought i needed a 28 inch barrel in a Airgun to get 1050 fps with 40 grain...You can do it with 17 inch in Airforce...The same combo with doug valve and 28inch barrel 1165fps-1200. Im handi cap...Im so happy with accuracy with12mm 17 inch barrel Airforce Condor..Even with moderator very short and Light...I can carry with cane or crutches...Anyways so happy to finally have a accurate 22 cal slug slinger for Legal Pa small game hunting on my property...Thanks AGN friends that helped me along the way..