Create Big Cannons 5.11.0, now supporting Create v6.0.9 on NeoForge 1.21.1 and Create v6.0.8 on Forge and Fabric 1.20.1.
You will need to update Ritchie's Projectile Library to v2.1.2 on 1.21.1.

Added:

• Added view transparency config for molten metal fluids
• Added ability to top up cannon cast fluids in Creative
• Added bronze and steel ingots and blocks (yes, after over 3 years)
• Added ability to combine different propellant types
  • By default, big cartridges must come before powder charges
• Added Inertia Fuze and Delayed Inertia Fuze

Changed:

• [1.21.1] Updated Ritchie's Projectile Library dependency to v2.1.2.
• Changed cannon drill bit texture
• Changed how cast iron is made; compacting now requires coal or charcoal
• Big cannon propellant compatibility data pack format different; maximum_amount => maximum_amount_ahead
  • Now based on maximum amount of propellant of block type ahead from first block type of file
• Increased nethersteel screw breech max stress to 10 charges
• Increased steel screw breech max stress to 8 charges
• Changed Impact Fuze and Delayed Impact Fuze trigger condition
  • They now do not trigger if the projectile is destroyed on impact or if they bounce/ricochet
• Updated block armor compatibility for Copycats+ v3.0
• Updated FramedBlocks compatibility for FramedBlocks 10.5
• Create Big Cannons should be playable with Create v6.0.7.
• [Developers, NeoForge] CBCNeoForgeRegisterEvent has been removed in favor of accessing CBC registries via RegisterEvent.

Fixed:

• Fixed positioning of Creative Autocannon Ammo Container screen text
• Fixed display and attack stats of ram rod and worm items
• Fixed default stress values for CBC not registering
• Fixed fluid shell tooltip when potions contained
• Fixed cannon drill model pipe UVs
• Fixed incomplete autocannon block waterlogged state on completion
• Fixed autocannon not syncing creative connections
• Fixed incorrect top-bottom cannon cast merger fluid capacity
• Fixed cannon builder assembly and layering collision
• Fixed white seat flickering when changing autocannon seating when Flywheel is on
• Fixed tracer spacing of regular Autocannon Ammo Container
• Fixed upside-down cannon mount rendering with Flywheel
• Fixed turning cannon carriage wheels when turning autocannon
• Fixed positioning of player after dismounting autocannon on cannon carriage
• Fixed missing FramedBlocks block armor properties compatibilities
• Fixed honey bucket and chocolate buckets not showing up in creative tab
• Fixed melting basin ponder category and pump orientation
• Fixed sliding breech and quick-firing breech breechblock rendering
• Fixed cannon cast error fluid name display
• Fixed creative autocannon ammo container screen display title when accessed in block form
• Fixed dispenser behavior of molten metals