I don't believe it.
Heavier shells tend to retain velocity over a longer range. Hence the reason 3.7cm flak has over twice the effective range as 2cm flak even though both are high velocity weapons. BK 5 should have been accurate to a range of at least 2km. And it's a foregone conclusion that a single 5cm mine shell will seriously damage any aircraft.
Effective range is much different in the air than on the ground. In the air the higher MV of the Mk-103 offsets the higher BC of the Bk-5. Secondly, the curvature of the trajectory at those sorts of ranges means that at 2000 M, you might fire off the hole magazine WO hitting anything. If the curvature of the trajectory goes above or below the fuselage, then aim off is required. This is how Point blank and effective range is determined. With the Mk-103, the bullet stream is a very narrow cone, centered on the line of fire. This dispersion helps give it a longer effective range because of the "Shotgun" effect. That is missing from the Bk-5. IIRC, the maximum range, not effective range was listed as 1,200 M for the Bk-5. The effective range for the Mk-103 was listed as 1,000 M. Take it for what it is worth. Also a Google search should find the fighter weapons page with a list of all WW-II guns and ammo. Lots of neat data there.