Depending on the barrel length, velocity might actually start dropping
before the bullet leaves the barrel! Various experts have said that with most 22 LR ammo, a barrel over about 17 inches reduces the velocity. It's a matter of the pressure being exerted on the base of the bullet VS the friction of the barrel.
Barrel length aside, the bullet starts slowing down the instant it leaves the barrel. The bullet's momentum and the gas behind it launch it into the atmosphere, and the air it encounters exerts resistance, regardless of the bullet's nose profile. Pointed bullets are affected less, but all are affected as soon as they leave the gun. If your bullet hits dead-on at 25 yards and higher at 50, it means the gun's sights are set so that the bullet is rising out to 75 yards or more. Bullets don't climb unless they're pointed up.
If you point a gun level to the horizon, and fire it at the same time you drop the same weight bullet from your hand, both will hit the ground at exactly the same time. Physics involves laws and rules, and they can't be bent, negotiated with, or changed, regardless of what some advertisers would have you believe.