Quote from: Quax on June 18, 2011, 09:02:17 AM
How do they stack up against one another. Is there one better than the other? For instance is a remchoke better than the standard invector since it is a longer tube? Does a .730 or .742 bore have an advantage over a .723?
You asked the "million dollar question" and one that usually inspires a lot of debate among shooters. In my experience, it's all about the design of the choke, the internal geometry that determines performance.
For many years the degree of choke has been determined by constriction. Degree of constriction is determined by the inside diameter of the shotgun bore minus the exit diameter of the choke tube. If you had a barrel with an i.d. of .740 and a choke tube with an e.d. of .640, you had .100 of constriction.
Formulas were determined to produce Improved Cylinder, Modified Choke, Full, etc. You simply used your barrel i.d. and the e.d. (constriction) of your choke to determine the true choke of your gun.
That formula is still used by hunters and clays shooters in particular and is often cited by others. Those formulas were determined years ago when lead shot was the only type available and they still work pretty well for that purpose. New wads and better (harder) shot have however negated some of the real value of those formulas.
Then when steel and other types of shot were introduced, it really complicated matters since that shot holds together longer and produces tighter patterns than traditional lead shot.
Turkey chokes seem to be in a world of their own. For those unfamiliar with the sport, the chokes that we use are excessively tight. Since in most guns, a choke with an exit diameter of .690 is considered to be a "full" choke and the tightest that they may have heard of, a choke with an e.d. of .650 or even .675 seems excessive to non turkey hunters.
The engineers at Browning, for example, recommend a turkey choke with an exit diameter of .640 for use with their Invector Plus barrels that have an i.d. of .742 or over .100 of constriction. Others may use chokes much more open with these guns and consider them to be perfect. It's really all about the design of the choke, not about a formula for constriction.
Lastly, I have some guns with very tight bores, a Benelli with a .717 for example, that shoots very well and I have a BPS with a .742 that shoots exceptionally well. Shotguns are funny things. Some just shoot better than others, regardless of brand or barrel i.d. It's the quest for the perfect turkey gun, choke and shell that makes this such an interesting sport.
Thanks,
Clark