Need help sighting in 870 smoothbore.

[JimG]

Looks like I'll need to use my trusty 12 gauge 870 Express for deer this year instead of my inline ML. I've had a fixed I/C choked smoothbore barrel with good iron sights for years. I've just never used it. The rear sight is a semi-buckhorn with a white triangle pointing up. The front sight is a white bead on dovetail. You line the bead up on the point of the triangle and you are good to go. I'm using Remingtons Slugger 1 ounce foster slugs @ 1560 advertised fps. The problem is the targets I'm aiming at. I'm having a devil of a time seeing the target dots at 50 and 75 yards. If I use a larger target circle like a 6" circle then it throws my shots high. A small circle my shots go low. Any deer at 25 yards is dead period. I'm just having trouble at 50 and 75 yards. Anyone care to explain how they go about sighting in the IRON sighted smooth bore slug gun? Are you using a 6 o'clock hold or a 'dead on' hold? If you are using a 6 o'clock hold, then what size target dot are you using? Please don't suggest a cantilever rifled barrel with a scope or a saddle mount and scope for my existing barrel as money in the household is now extremely tight. Thanks in advance.

[jeager106]

You MUST have adjustable iron sights. Fixed sights are a handicap and not much beter than lining up two beads on a vent rib s.g and spray and pray.
With GOOD sights you might be quite surprised at how accurate the smooth bore with rifled slugs can be.
You must:
1) keep your barrel free of the inevitable lead build up.
2) keep the tension on the barrel nut tight and UNIFORM.
3) Thoroughly clean your gun every 5 shots no matter what you think it looks like. Flbow grease my friend, or......
4) Use a 5/8 dowel of ramen wood from any hdw. store.
Cut a 4 inch or so slot in one end. Cut a scotch pad (wet with cleaner)  to fit tight in the bore. Chuck in large hand drill and rotate that up and down your bore several times.
use a cleaning rod with cloth wet patch to remove all the lead crud your scotch pad shook loose.
Once in a while I can muster a 2 inch groups at 100 from a smoothie and Brenneke K.O. slugs.
Average is 4 inches or so, plenty of minute of bambi. The shotgun in 12 bore is deadly on deer.
Of course you have to hit the thing first.
If you have question feel free to ask and I'll do my best to get you some answers.

Adjustable sights, tension on the barrel nut, keep her clean.
Once properly sighted in DO NOT remove the barrel 'till seasons end.
Best wishes and good shooting.

[JimG]

It does have an adjustable rear sight. Both windage and elevation are easily adjustable. In what way does the barrel nut tension effect accuracy? This is something I've tinkered with. I've noticed no change in POI left to right. I'm not sure if it effects POI up and down since I'm having trouble with targets right now. I try to tighten the nut by hand the same each time. If I could figure out a way to use my torque wrench I would!

[Graybeard]

The first thing you need to do is to forget using 6 0'clock hold. That's fine on targets but don't cut it on game. You need the shot to go where your sights point ie, dead on for game. I agree it's tough to do fine work with coarse irons but it can be done with practice.

With a smooth bore you need to be using Foster slugs NOT sabots.

I'd sight in about dead on at 50 yards and if you need to shoot further on game and feel you're up to the task aim a wee bit high. At 50 yards a 4" dot or square should be about right but if needed use a 6" target dot/square. Don't aim at it for six o'clock hold but hold for the center. Adjust your sights as necessary and when shooting game know that the bullet hits where the top of front sight rests.

I don't agree on the previously noted cleaning cycle I feel it excessive. Get one of the fuzzy rods to run down the barrel for cleaning and you'll likely need nothing more ever. Clean only when the crud build up tells you it's time. That might be five shots or 55 shots. Let the barrel tell you when it needs cleaned.