Hk you are wrong 10 rounders are grandfathered you may keep 10 rounders but other than at a range can only load 7 after the April date. You will not have to give up or modify your existing ten rounders to hold 7. After the date the only mags allowed into ny except curio and relics need to be 7 or less.
At that point I figure my wheel guns are going to get a lot of carry wear. Can't see the point of carrying a 9 with 8 rounds in it versus a six shooter