Opening up choke
- Thread starter scot
- Start date
If they are not chrome lined I can do it... done hundreds over 50 years... $40 to $50 per barrel. I recommend doing the forcing cone as well $45 per barrel.
SHOTGUN BARREL ALTERATIONS FOR STEEL SHOT
Forcing Cone Alteration:
Factory shotgun barrels usually have a fairly short and abrupt forcing cone. The forcing cone is the tapered area just ahead of the chamber where the shell is contained. Altering the forcing cone, so it is one and one half or two inches in length, reduces recoil and improves the pattern density. Trap shooters and skeet shooters have been doing this for many years. It is a good benefit to the steel shot user as well.
Choke Alteration:
Choke designation from the tightest to the most open are:
Extra Full, Full, Improved Modified, Modified, Skeet II, Improved Cylinder, Skeet I, and Cylinder Bore.
Steel shot does not require the constriction that lead shot needs, to produce good patterns. In fact too much constriction, causes poor, erratic patterns, and in some cases, permanently damages the barrel. I have seen barrels bulged at the choke, I have seen barrels where the choke split right open, from using steel shot.
For steel shot, with thin barrels, chokes should be altered to at least Skeet II. Often, over & under, and side-by-side shotguns, are best altered to Skeet I and Skeet II chokes. Heavier barrels can be left at Modified choke but may see an improvement in the pattern if opened slightly.
SHOTGUN BARREL ALTERATIONS FOR STEEL SHOT
Forcing Cone Alteration:
Factory shotgun barrels usually have a fairly short and abrupt forcing cone. The forcing cone is the tapered area just ahead of the chamber where the shell is contained. Altering the forcing cone, so it is one and one half or two inches in length, reduces recoil and improves the pattern density. Trap shooters and skeet shooters have been doing this for many years. It is a good benefit to the steel shot user as well.
Choke Alteration:
Choke designation from the tightest to the most open are:
Extra Full, Full, Improved Modified, Modified, Skeet II, Improved Cylinder, Skeet I, and Cylinder Bore.
Steel shot does not require the constriction that lead shot needs, to produce good patterns. In fact too much constriction, causes poor, erratic patterns, and in some cases, permanently damages the barrel. I have seen barrels bulged at the choke, I have seen barrels where the choke split right open, from using steel shot.
For steel shot, with thin barrels, chokes should be altered to at least Skeet II. Often, over & under, and side-by-side shotguns, are best altered to Skeet I and Skeet II chokes. Heavier barrels can be left at Modified choke but may see an improvement in the pattern if opened slightly.
It's not hard to find it discussed on many different forums. It's not something I have ever had the urge to test myself so I apologize if it's something that is not true or overblown. Opening the forcing cone sure seems to improve patterns at least a little up to a lot.
It's quite possible a dedicated slug gun with a quality rifled barrel would benefit from a tight chamber and short throat accuracy wise... but with a smooth bore I think it means diddly squat. The benefit to the shot pattern and slight reduction in recoil with a long forcing cone overcome any accuracy problem with a slug.
