McQuinn's Thirty-first Division, like most other Blakist formations, did not appear until the Jihad. As such, little is known of McQuinn's early life and military career.
In December 3067, the Word of Blake launched its Jihad on the Inner Sphere. McQuinn and the Thirty-first, along with heavy WarShip support, formed the initial attack force on the Federated Suns world of New Avalon. While the WarShips conducted orbital bombardment on the planet, McQuinn and the Thirty-first landed on-planet and advanced on Avalon City. The under-strength 10th Lyran Guards was the first unit to oppose the Blakists, engaging them at McCarel Farm. The Purity of Faith attempted to bypass the Revenants with a screening force, but the Tenth punched through, attempting to hit the Thirty-first's supply train, a trio of Prairie Schooners. Despite being outnumbered, the Tenth managed to inflict significant damage on the relatively inexperienced Thirty-first before they were forced to pull back with heavy losses. This bought the defenders enough time to regroup and form an effective defense against the Blakists. After three weeks of fighting, McQuinn and the Thirty-first were forced off-world by the defenders. They nevertheless remained in-system with the Word's naval forces in orbit, effectively blockading the planet.
In February 3068, the Thirty-first was reinforced by the 36th Division, a much more experienced unit. The Blakists hit the planet once again, but found the defenders had been reinforced by the Davion Assault Guards, the Davion Heavy Guards and the 3rd Davion Guards, as well as the Beta Regiment of the mercenary 12th Vegan Rangers. In over a year of near-constant fighting, McQuinn, the Thirty-first and Thirty-sixth opposed the defending Davion forces under the command of Marshal of the Armies Jackson Davion, with both sides taking heavy losses. Ultimately, the Word of Blake was beaten back again, with both units withdrawing to orbit. Once more, the Blakists settled into a blockade.
That essentially remained the status quo until December 3072, when the 44th Shadow Division arrived. This elite Manei Domini unit rallied the two divisions already in-system as well as the Bronson's Horde mercenary company in yet a third assault on the planet. Though it took several months more of vicious fighting with all parties taking heavy losses, the Blakists were finally able to take Avalon City in February 3073. This did not break the defenders, however, who continued to resist with all they could muster. With setbacks in other areas, all three Word of Blake units were ordered back to the Protectorate in September 3074, though by then losses to the Thirty-first were so severe they had effectively been absorbed by the Thirty-sixth.  It is unclear if McQuinn survived the fighting on New Avalon.
- Jihad Turning Points: New Avalon, p. 7, "Combatants: Thirty-first Division"
- Jihad Secrets: The Blake Documents, p. 94, "31st Division (Purity of Faith)"
- Jihad Turning Points: New Avalon, p. 8, "Unwelcome Guests"