HMCS Regina’s gun refit a cut above

Ashley Evans, Strategic Communications Officer, FMF CB/CS — Not every day you see a Bofors 57mm rapid-fire gun turned inside out, but if you walk past the Above Surface Weapons Work Centre in Fleet Maintenance Facility (FMF) Cape Breton’s (CB) D250 building, that’s exactly what you’ll see.

In March 2021, HMCS Regina’s big gun was removed for an 18-month overhaul as part of the five-year Tiered Readiness Program. The timing was ideal as the warship has entered its scheduled lifecycle refit.

An overhaul of the Halifax-class frigate’s weapon is as complex as you might think.

Upon completion, 8-10 workforce members in work centre 162A will have put in approximately 1,100 – 1,500 work hours. Various team members have also been involved across 13 other work centres: 163 Fire Control, 142 Quality Control, 234B and 211 Engineering, 125 Chemical Cleaners, 143 NDT, 164 Machine Shop, 111 Labourers, 122 Shipwrights, 113 Welding, 112 Boiler Shop, 124 Riggers and Crane, and 123 Paint and Graphics.

During this overhaul, the gun is wholly disassembled; everything is stripped out and run through various tests to check for damage and cracks, including non-visible cracks inspected in Non-Destructive Testing (NDT).

“This is a complete teardown,” said Tim Christy, FMF Work Centre Supervisor for Surface Weapons Shop (162A). “We will then assess and repair  all compromised parts.”

This five-year overhaul thus far includes the replacement of aged-out hydraulic hoses and complete assessments of the breach-ring assembly, magazines, cassettes, and hoist system. The Breach-ring assembly, made of 50-60 parts, holds the firing components. Work completed on the magazines, cassettes and hoist system is predicted to take over one hundred hours alone as the team manually tests the movement of the parts required to load and balance ammunition.

Following the repairs completion and before re-instalment onboard HMCS Regina, Work Centre
162A will complete Set-to-Work assessments to ensure all systems are working and tested to the best of their ability in-house, including checking for hydraulic leaks and alignment, essentially proving the big gun is working properly.

“Meeting deadlines and getting parts is the most challenging part of this project,” says Christy. “We can’t fire live, but we aim to achieve the same ‘first time out of the box’ perfection, which is not as easy as it sounds.”

Following meticulous set-to-work testing, the Bofors 57mm will be lifted by crane back onboard HMCS Regina with an expected completion date of June 2023. Once back on board, the FMF CB teams will take two to four weeks to complete installation work, bringing the gun back to operational status. Harbour Acceptance Trials, which FMF CB Engineers and occasionally Journeypersons attend, are expected to wrap up this August. The finishing touches to the cupola will be completed soon; a new upgraded graphic representing HMCS Regina will be placed where old painted artwork used to sit.

Following this overhaul, the warship’s big gun will receive routine inspections and maintenance every six months until the next five-year Tiered Readiness Program.

The most rewarding part of this 18-month overhaul, says Christy, is achieving reliability so that the sailors can do their jobs effectively.

“We go anywhere they need us to fix it and to give them that capability, that’s rewarding,” he said.

The Bofors 57mm Gun

The Bofors 57mm rapid-fire gun serves as the ship’s defence but can also fire upon surface and shore targets. It uses various types of ammunition, including, but not limited to, High-Capacity Extended Range used for surface targets and Pre-fragmented High Explosives for anti-aircraft purposes.