How to reduce waste spooling your reels?

[lefty]

I'm workin' on a plan to respool my smaller reels with fresh line -- but the thought occurred to me that this could be a wasteful proposition. If I have two reels that hold 200 yards at a given size, I'll need the 300-yard packages of line. But after buying two packages and spooling two reels, I've got two 100-yard chunks of waste, amounting to 33% of my purchase.

I allowed Dick's to wind a line one time and was disappointed at the lack of tension on the spool, so I'd kinda rather do it myself.

I'm planning to wind 'em with braid this time instead of mono - so the "waste" won't be any good for leaders... and the 1/3 wasted cost will smart a little bit more...

I do need to replace one of the reels -- so I could choose the second reel so that its capacity added to the existing reel's capacity adds up to 330 yards... But aside from that, is there a more stewardly way to accomplish the task?

Thanx - lefty