Design & Construction
The 300 MS is built around a fiberglass hull with a long, shallow keel and 4,500 pounds of lead ballast, yielding a substantial ballast-to-displacement ratio of 39.13. This configuration, combined with a relatively small rudder mounted behind a large propeller aperture, makes directional stability a defining trait. The high cabin trunk and pilothouse dominate the profile, while side decks were kept intentionally narrow to maximize room below. On the foredeck, a teak anchor platform sits atop a molded fiberglass structure, and a hawse pipe feeds chain into a forepeak locker since there is no dedicated anchor locker. Notably, owner discussions reflect an absence of widespread structural concerns, suggesting a build quality that has aged typically well.
Rig & Handling
The 300 MS carries a masthead sloop rig with a traditional single-spreader setup, and its reported total sail area of 477 square feet produces a modest sail area-to-displacement ratio around 14. A traveler mounted forward of the mast sets up a self-tacking jib for easy short-handed sailing, though genoa tracks on the toe rail allow for a larger headsail when conditions warrant. While many boats have since been refitted to lead all sail controls back to the pilothouse, the rig originally had halyards terminating at winches on the mast. Under power, the standard diesel (specified as a Westerbeke W-46, though some records list a Vire engine) provides a real-world cruising speed of 6 to 6.5 knots, burning roughly one gallon per hour, which gives a theoretical range that matches its cruising ambitions. The full keel helps the boat track like it's on rails, though the trade-off is less-than-stellar maneuverability in tight marinas. Under sail, the boat is not a light-air performer and won't point high or accelerate out of tacks, but in a 10-to-15-knot breeze it settles in and delivers steady, comfortable progress on a stable platform that doesn't demand heroics from the crew.
Accommodations
The interior is where the 300 MS truly separates itself from typical 30-footers. The pilothouse creates a second living space with excellent visibility through real glass, and the lockable companionway is integrated into its forward bulkhead. From the factory, the aft end of the pilothouse was open to the cockpit, but most owners have since enclosed it with canvas or a solid structure, and some go further still with a fully enclosed cockpit that more than doubles the boat's usable living area. Below, an expansive galley to starboard features a two-burner stove, a large icebox, and 75 gallons of water capacity, while a dinette to port can be lowered to create extra sleeping space. The forward V-berth is generous for a boat this size, with a hanging locker to starboard and a functional head to port. Large hatches on the cabin top and pilothouse provide ample ventilation.
Known Issues
While the 300 MS has aged well structurally, a few items deserve attention during any survey. Pilothouse windows are a known discussion point among owners, often signaling potential for leaks or deteriorating seals. The steering system should also be inspected carefully, and any buyer should confirm that the emergency tiller is present and fully operational.
Refits & Ownership
A fully enclosed cockpit is a common upgrade across the fleet, transforming the boat into a true all-weather cruiser and dramatically expanding its livability. Another common refit involves bringing all sail controls aft to the pilothouse, eliminating the need to go forward in heavy conditions. These practical modifications align perfectly with the boat's intended role as a capable liveaboard or extended cruising platform.
The Verdict
The Cape Dory 300 MS is a purpose-built platform that consciously trades sailing performance for comfort, protection, and flexibility. It is wide, heavy, and stable, a boat that feels planted rather than skittish, with a flat run aft that reduces stern squat under power and a hull speed just shy of 7 knots. For the sailor whose logbook favors gunkholing in shallow anchorages and making steady miles in comfort, this rare and well-built motor sailor remains a compelling choice.
Pros
- Exceptionally stable and predictable motion under power and sail
- Pilothouse provides a protected second living space with excellent visibility
- Interior volume is generous for a 30-foot vessel, with a functional liveaboard layout
- Full keel and heavy displacement deliver confident, low-workload tracking
- Strong build quality with an absence of widespread structural complaints
Cons
- Sailing performance is modest; not a light-air performer and won't point high
- Maneuverability in tight marinas is compromised by the long keel
- Pilothouse windows are a known source of potential leaks
