Why don't you try it with your 70-300mm?
a) It is extremely soft after 200mm. The 50mm on D3300 gets much better image. Yesterday I shot the moon with 50mm. At 100% it was 100 pixels, but much sharper than the zoom at 300mm.
b) It is a pre afs lense so manual focus on D3300. Yes I will try it out between 100 and 150.
At present I am trying to get best focus from the two primes - 50mm manual and 35mm AF. Believe me most of the time for closer shots the 50mm MF is more accurate than the 35mm AF, which gets confused by a lot of small details and either focuses to the details at the back or to front. Getting it to focus on a stamen bang on is a feat. I am getting better day by day, so till I can repeat the sharp focus, I will keep at it.