I've used the trick of filing the lead tip off Partitions for tube magazine lever-actions from the .25-35 to .33 WCF, going back to before Nosler actually started making a 170-grain roundnose Partition for the .30-30. They have always shot and expanded well. (In fact the 120 .25 Partition filed back results in a 117-grain flatnose!)
Just tried it with a 225 .35 Partition. Filed down to the jacket, it resulted in a 220-grain flatnose--but you can also file them even down into the jacket if you want a wider flatnose. It's easier, however, to maintain a consistent weight by stopping at the jacket.
