This is from my 3-rd grade Chinese 语文 book (transcript is here):
Question: Why is there repetition of the measure words in 一把把小扇子 and 一枚枚邮票?
I would guess this is for poetic reasons, but I'm not sure. I've never seen this before.
The use above seems different to the question What is the meaning of "一把把" on "他更是一把把她的书包给枪了过去“？ where it seems only the first 把 is the measure word.