A 4" barrel is great, a 5" barrel is perfect, a 6" barrel is alright though it's getting a little weighty out there, and an 8" barrel is just too long!
I hate to resurrect an old thread, but there's a lot to be said for the older Rugers.
When underlug barrels are the issue, a 6-inch barrel is near perfect. Give me a GP100 6-inch and I'd trade it for a Glock, and I don't much care for Glocks at all. And though I'm sure there are people who use 6-inch GP100s for hunting, I'd dump it for a rifle. And though I see beauty in 6-inch S&W 686s, the balance of a 6-inch GP100 is horrible. Ruger takes steel it would otherwise use for grips and moves it to the barrel to make it as front-heavy as it can. The underlug barrel makes shooting it at the moment a more accurate experience, but the guns are almost always carried more than they're shot, so packing steel into the wilderness can be an unpleasant outing, especially if you're using a scope.
The S&W 686 is made of forged steel, and though they're beautiful and deadly accurate, as hunting guns they also can be a bit heavy. When the 686 was first introduced, many loved the 6-inch barrel. I got one of the first models and never sent it in for the recall. A friend got one like mine (a 6-incher) and it never had any problems. I never fired mine and kept it as a collector's model. I preferred shooting my 6-inch Security-Six despite the fact that I could shoot the 686 better. When my friend hunted wild pigs for barbecue, though, he preferred his S&W 66. When we went shooting, he preferred his 686, but when hunting he liked his 6-inch 66 (like the one above). It had a much better balance, and though he rarely shot magnum loads, he used them to hunt. I really loved that gun, though.
The Ruger Security-Six was very similar to the S&W 66, but more robust. And it can be easily carried while hunting, hiking, fishing and camping.
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