Master Model 1/700
British 12-pdr (3"/50) 18 cwt QF Mk 1 Barrels

Reviewed August 2016
by Timothy Choi

The 12-pdr (3"/50) Mark 1 guns provided Dreadnought and her predecessors with quick-firing protection against torpedo boats and small craft. These brass barrels feature bored out and flared tips.
26 barrels come in this set, meeting the high standards expected from Master's previous products, though my version came with a lot of loose machining artefacts in the bag - they do not affect the barrels themselves, thankfully.
It consists of a simple sheet with illustrations. There is no instruction aside from using a 0.3mm drill bit and informing you which historic ships employed this weapon.
Final Thoughts

With Trumpeter's recent release of HMS Dreadnought in various periods, this set is no longer limited for use with Combrig's venerable line of resin kits. It also pairs well with Master's set for Dreadnought's 12"/45 Mark X main batteries, SM-700-043.

This is set # SM-700-044, which typically retails for well under $6.00 US.  Check the list of stores that sell the line on the Master Model website.