Lower average cost by buying and selling small portions?

I was taking of lowering the average cost of one of my stocks by buying when low, reselling that portion after a rise, and then buying again.

An example would be let’s say I bought $1000 of ABC at a stock price of $100. But now it’s $60. Could I buy $200 right now and sell when it rises to 75? And once it drops to 70 buy in again with that same amount?

Does this seem like it could work? Btw I still plan buying monthly but I was wondering if you could do this to speed up the process.