Sorry, not too impressive, myself- just a broke-down old scattergun shooter. Would like to be helpful though, if you can live without me having to be impressive doing it. So, let's go through the questions and work on some answers.
Okay, so I'm thinking about a shotgun, for skeet shooting and/or home defense. I was just wondering...
Will I use the same choke for both duties? Should I buy a shotgun with a non-permanent choke, then?
Were I you, I'd not even use the same _barrel_ for home defense (HD) on one hand and any sort of formal clay games on the other. IMO, a shotgun set up for HD is handier with a barrel length from 18- 21". Be sure you stick to smoothbore though, more and more short barrels these days are rifled for use with sabot slugs. For a genuine HD gun choke won't matter too much- engagements are apt to be at ranges measured in feet rather than yards. At short range shotgun patterns will not have opened very much no matter what choke is used.
Nothing says you can't practice shooting at machine thrown or hand thrown clay pigeons with your HD gun (though some clubs restrict use of short barrels)- but if the point is to shoot clays and not practice with the defensive shotgun, you'll be better served with a longer barrel. A longer barrel gives you a longer sight radius and more weight out in front of your forward hand, which tends to help you swing better on fleeting clay targets. Usually a factory will make 26- 30" barrels for these sorts of uses. This sort of barrel is also better for wingshooting, if you ever get to go after waterfowl or doves.
Given that barrels on most modern repeating shotguns interchange quite easily, and given that there is a wide variety of lengths and types of barrels available, there is no need not to use a barrel suited to the task at hand. Manufacturers even offer combination deals, where you get one basic gun with two barrels, a long field or sporting barrel and a short deer or slug or defensive barrel.
Do the cheaper pump shotguns (870, 500, 590, and whatnot) come with fixed chokes?
Some do, some don't. Generally on new guns the longer sporting type barrels these days will be set up for choke tubes, while the shorter smoothbore defensive or deer/slug barrels have fixed chokes, mostly Cylinder or Improved Cylinder.
How hard is it to change the stock on a 500? There are a bunch on GunBroker that come with pistol grip stocks, and I know enough from shooting 20 guage single shots at scout camp that a 12 guage without a stock is probably gonna hurt.
Not hard at all, only simple tools required. Unless you're breaching doors or using a shotgun in a _very_ confined space, pistol grip only stocks are an unnecessary handicap for the shooter. And as you mention, often painful.
Any other comments you can add to help me in my noobness are greatly appreciated.
None of us are born shotgunners, all of us had to start somewhere as a noob. Some of us had the benefit of elders and mentors who took us in hand and taught us the ins and outs of the art and science of shotguns. We are the lucky ones, to have been helped, guided and trained from childhood. I wish it could be so for every child in this country.
"The Old Man knows pretty near close to everything," is the first line in one of the books mentioned below. There is a time in life when the wisdom and experience of the elderly can more easily be imparted to the young without having to fight through the barrier of the generation gap, past the adolescent need to separate from those who came before and be different. It is a magical time as are so many among the young, when horizons are closer and worlds are smaller and old men might loom more important in the great scheme of things. It's sad to see this time missed out on in so many cases.
But no matter- there is training available in almost all areas of the country. Hunter safety courses and the NRA classes are probably the lowest common denominator available in formal training. Learn safety first, no matter what. Informal training is as good as the trainer, so if you are going that route be sure you pick a good trainer. Any number of gun clubs offer training in smoking clays, and for defensive applications we are blessed with a number of world class trainers- people like Louis Awerbuck, Randy Cain and others of great skill.
The best advice I can give you is to always be willing to learn, and to enjoy doing it. Read. No matter what else you do, read. Many great lessons have already been set down in print, but if you don't find them and read them then they are useless to you. Start with the "101" threads here, and the links to the old TFL threads that are stickied at the top of the index page. Books? Lord yes, dozens of them, too many to list. But no matter what, don't miss Robert Ruark's _The Old Man and The Boy_ for the heart, soul and spirit of things, and Bob Brister's _Shotgunning: The Art and the Science_ for the how- to and technical stuff. Links:
http://www.amazon.com/gp/product/08..._2/103-0495136-7885463?_encoding=UTF8&s=books
http://www.amazon.com/gp/product/0832918407/103-0495136-7885463?v=glance&n=283155
Good luck, and Stay Safe,
lpl/nc
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