Handling straight rosin is nightmarish. You couldfreeze it so it solidifies and try to get chunks in the cart? I never was able to get reclaim rosin out of my hoohah tubes without a big mess/headache.

I only ever syringed activated rosin cooked into coconut oil for pill cap edibles. Syringing regular rosin would be awful.

I understand the appeal of pens and carts but like maybe just get a vaporizer thats actually meant for concentrates if you want to go that route. Its the easiest thing in the world to heat a DV tip and then lay some concentrate on the inner walls and heat it back up. Or get some vape wool and saturate it with oil and load it in the tip.