MD said:
What is the benefit of doing a long forcing cone alteration?
I had my old 870 reamed out to modified from full choke, but in another thread here, there was a mention of long forcing cone alteration.
Should I have had that done to my old shotgun too?
Is the forcing come generally different for steel?
Am I wrecking the barrel of my 1957 Wingmaster?
You are not wrecking anything if it is done properly.
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, 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.
I do this alteration only on barrels that are not chrome lined. It usually costs $80 per barrel to alter the choke and the forcing cone.
