Shot shell loads can be very effective at close ranges. A hunting buddy loaded # 6s for his .44, and was deadly on close range rabbits with it.
Off course if the snake is a threat, it is probably very close. A .38 wheel gun is very versatile with handloads or the wide variety available off the shelf. The model 60 is a great little gun, available with a 3" bbl. for a bit more versatility and accuracy than the shorter barrel version. Be aware that the original model 60 (stainless) or 36 (blued version) are .38 only, not .357 as someone else mentioned. Newer versions in a slightly larger version are .38 or .357. That makes alot of bark in a pretty small package. I agree, the "judge" is an oversized whatsit.