I'm about to build my Remington 870 into something a little more tactical so that I can shoot 3-gun matches.

Currently I've got a 20" rem choke barrel, and standard stocks.  I'm planning on adding a speedfeed (solid) stock w/pistol grip, a sidesaddle, and a magazine extension.

Any other tips from you guys who have built up a 3-gun shotgun?  Can I use the 3 round extention with a 20" barrel, or is that too long?  Do you guys like putting the sidesaddle on the left side of the shotgun for a rollover reload, or on the right so you can reload as you go?

Thanks!

USPSA rules for Limited Class allow a total of 9 rounds in the gun, 1 in the chamber and 8 in the tube.  This will equate to about a 22" barrel.  No ports, optics, muzzle brakes allowed.  I've never seen a side saddle on the right side.  You might check out 3-Gun Gear more side saddle and other ammo carrying options.  I've found an oversized safety button useful as most starts are high ready safety on.

If you go with the Remington 21" Turkey barrel and add an extended choke tube, it somes out right at 22" and will fit flush with a +4 magazine extension.