As the US progressed into WWII, the M1918 "Schneider" 155mm Howitzer was gradually replaced by the M1 155mm Howitzer, though I understand the Schneider continued to see service throughout the war. The standard HE projectile for the Schneider (pre-war) was the M102 and for the M1 was the M107. I understand one of the differences between these two projectiles was that the M107 had a wider rotational or driving band. I could swear I remember reading somewhere that the M1 fired the M102 okay but there was some loss of accuracy as compared to the M107 due to some size difference (possibly the driving band?). Conversely, I thought I remembered that there was a problem firing the M107 through the Schneider due to some size difference in shell, chamber or possibly tube size? Now I can't seem to find any reference that suggests that there was any compatibility problems with ammunition between these two Howitzers. Does this sound familiar to anyone or did I just have a brain fart?