I doubt without productivity modules your recipes are cost effective.

One rocket yields 5k asteroid-ore which is broken down into
- 5000 x 0.4 x 50 = 100k iron ore
- 5000 x 0.4 x 50 = 100k copper ore
- 5000 x 0.1 x 50 = 25k uranium ore
- 5000 x 0.1 x 50 = 25k coal

https://wiki.factorio.com/Rocket_part
The rocket by itself costs:
- 9,500 Coal
- 35,648.148 Water
- 39,907.407 Crude oil
- 77,500 Copper ore
- 89,100 Iron ore

Together with the space-drill it'll exceed the resources gained from asteroid-ore precessing.
I would increase either asteroid-ore gained per launch or chances for chunks (chance is calculated per product not as total so you can exceed 100%)

But,who would mass launch rockets without PM3s?

Full of PM3s save 40% resources. I was launch rockets without PM3s for 500 hours ! ( T.v T )

I should compute the coal->plastic conversion rate with coal liquifaction. With production modules, it might actually be cost efficient. 25k uranium easily pays for whatever power it costs.