I'd like to start shooting 3 gun.  I've got a Rock River AR with Eotech and a Springfield 1911.  Most of my shotguns are over/unders.  I do have a Remington 11-87 with a 28' vent rib barrel.  I've found a good deal on a 21" rifle sight/Rem choke barrel.  Is this suitable to start out in 3 gun?  There is no gas compensation system on these barrels (designed for slug use), but for now, I can load heavier loads for the shot stages.  Eventually, I'll buy a dedicated shotgun for competition, but would like to shoot a few matches with the one I've got before deciding on a major purchase.  

The 21" barrel will be ok, but depending on the match, you may not be able to put a very long mag extension (some rules say mag tube can't be more than 1" longer than the barrel). However, one good thing is that the shorter barrel length will make it easy to use thorugh ports and index from target to target.

I run a 26" vent rib RemChoke barrel on my 1100, and with a mag tube that matches the length of the barrel I get 9 + 1 (sometimes 10 + 1 if I really mash in that last shell). I think that barrel length is a good compromise (not too long to be unwieldy, and long enough to be able to put on a longer mag extension).

Thanks for the input.  I have a 26" vent rib barrel now, was just concerned about the bead sights for any slug stages.  I've never tried shooting slugs through the barrel.  Maybe I'll give it a try.  Just thought the rifle sight barrel would be better suited.

Tcmers,

Don't know about your club, but my club shoots steel knock down plates at 80 meters using rifled slugs.  Everyone with bead sights has a hard time.  Most people are using peep or rifle sights on their shottys.  I use an 870 with an 18" bbl but I put a Mesa Tactical Adaptor on it which allows me to run a Crane/LMT stock, pistol grip, and a dot reflex sight because I couldn't hit $hit with the bead sight.  I just cut my barrel down to 14" so it points better for the CQB stages and I still can knock down the 80 meter plates first time every time with the Reflex II sight.  This picture was taked before I had the barrel shortened.

Hope this helps,
MadDog

+1 on the 18" barrel.

You shouldn't need anything longer than that, unless your shooting so long targets.

I use this one for 75 yard targets, works for longer too.......



Cavalry Arms sst-870 system with a Hakko BED-35 sight, tacstar mag tube and barrel shroud.  

Works pretty damn good