Largest handguns I own are a 500 Linebaugh Ruger Bisley, a 50GI Glock and 1911A1 from Guncrafters Industries and a Super Redhawk in 45 Colt / 454 Casull .
Then there is my TC Contender in 45-70 .....:o)
Thats as big as I can afford.
Stay safe !
Get yourself a 444 Marlin barrel for that Contender. Great fun.