Gator if your BT65 is a .22 then I would use the JSB monsters tune down to 900-950 the 19gr are a little light for that gun. also try to get three different head sizes and see which size groups the best then try pellets in that size. it seems like a lot of work, but it will pay off at the end. Me with that kinda power I would not go less then 21gr pellets.RECAP I see that it is infact a BT65 in >.25 the min pellet would be the JSB 25gr, the same rules still apply as far as weight and head size...
What size pellet fits that barrel?? That is one HECK of a group right there Baxter!!
Oh by the way the groves are called rifling, and at the very end of the barrel at the muzzle it gets tighter which is called a choke, both are needed for accuracy. Rifling refers to helical grooves in the barrel of a gun or firearm, which imparts a spin to a projectile around its long axis. This spin serves to gyroscopically stabilize the projectile, improving its aerodynamic stability and accuracy.
Quote from: Bwalton on July 30, 2014, 01:49:56 PMOh by the way the groves are called rifling, and at the very end of the barrel at the muzzle it gets tighter which is called a choke, both are needed for accuracy. Rifling refers to helical grooves in the barrel of a gun or firearm, which imparts a spin to a projectile around its long axis. This spin serves to gyroscopically stabilize the projectile, improving its aerodynamic stability and accuracy.The last time I saw a bore that large I was cleaning a 5"38 took a couple of guys just to get the wire brush down the bore.