How many times is the speed of a bullet in the middle of the barrel of a gun less than when it leaves the barrel?

Let the bullet move with constant acceleration a.
Path S1 to the end of the barrel through constant acceleration a and time t1:
S1 = at12 / 2
Path S2 to the middle of the trunk is half as long and will be covered in time t2:
S2 = S1 / 2 = at22 / 2;
t1 = √ (2S1 / a);
t2 = √ (S1 / a);
v1 = a * t1 = a * √ (2S1 / a) = √2aS1;
v2 = a * t2 = a * √ (S1 / a) = √aS1;
v1 / v2 = (√2aS1) / (√aS1) = √2;
v1 = v2 * √2 = 1.41v2.
Answer: The bullet velocity in the middle of the barrel is 1.41 times less than when it leaves the barrel.