Well the Canadian Rangers still use it so they are still somewhat in the system as new old stock. But as for use as a cadet rifle many Corps have a hard enough time securing range time for the .22s let alone a big bore rifle. Also, the availability of a range in close proximity to Corps which allow for "big bore". Next, there is the difference in body size, arm length and strength issues. I had cadets shoot regularly with the FNC1 and while it was "fun" most of the principals of marksman ship went by the wayside. You learn and develop marksmanship skills through constant practice not shooting the biggest gun on the block. The air rifle and the .22 which are in the system have a less round per cost than the .303. Something that has to be considered in this era of financial responsibility. Lastly, you need range staff who are qualified for "big bore". In the various Corps I have worked with (all three services) there were/are very few of us. Again cost involved to train up new staff, both dollar and time wise. The only advantage the ole .303 in relationship to cadets is in drill. At least it is real and not made of rubber. In closing there is also something to do with various international conventions on "Child Soldiers" which Canada is a signatory and if memory serves me correct was one of the causes for the removal of big bore shooting.