Formula Scoops completely inaccurate by weight - do I change?

I’ve been using Similac Pro Total comfort. The package says use a level scoop for every 2 oz. I wanted to try doing 5 oz, an odd number, so I tried doing the weighing method I’ve seen on this sub. When I weighed I found the scoops were off by 5-7 grams. So it would take 3 full scoops to get me to 5 oz. Basically almost an entire half scoop extra I should be giving my baby to get accurate measurements.

Should I start weighing the formula? I only question it because I’m going to be really changing the ratio of formula to water my baby has been getting the past 9 weeks he’s been alive.

Thanks for any advice