If you are going to shoot and load a screw in choked barrel, you have only two choices in picking wads that will properly seal the bore. A. The Thin, Overshot Cards, and B. felt wads.
You have to turn the wads or cards Sideways to the bore at the muzzle, and bend them enough to slide them down past the choke. The OS card will do this, easily, as will the soft, felt wads( no more than 1/4" thick) You have to use MULTIPLE cards or felt wads to build up the SEAL effect in the bore to keep the gases behind the wads and shot load. You can't do it with ONE, Thick wad, as might be done using a cylinder bore shotgun.
Try using 4 OS cards on top of the powder. Turn the cards alternating 90 degrees, so that the edges of the cards that are bent going through the choke, and then turning to square to the bore in front of your loading rod tip, are protected by the next card. Example: First card, align 12/6 o'clock; second card, align 9/3 o'clock; third card, align 12/6 o'clock. etc.)
Iron Jim Rackham, a member here who came up with a described this technique with pictures, showing his before and after patterns, and even some of the grouse he killed with his fowler, put a ball of harder wax lube between his 3rd and 4th OS cards, so that the lube was flattened and spread out when he seated that last card on the first three, and the powder behind it. On firing the shot, the lube was liquified, and lubed the bore as the cards exited the barrel, softening the fouling in the barrel to make it easy to clean, or simply reload the gun.
Then pour in your load of shot.
Finish by putting two OS cards down on top of the shot, both cards having off-centered holes poked into them with an awl, to allow the air between the shot and the OS cards to escape, to prevent "dieseling" of the OS cards. Why two? Again, to protect those edges, and make sure you have a good seal. This is particularly useful when shooting a DB shotgun, where there can be a chance that a load will shift in the second barrel when the first barrel is fired. 2 OS cards on top of the shot act like lock washers to each other, and have enough friction to prevent the load from moving forward on recoil of the first barrel.
Now, some like to lube a felt Wad, and place it between the OS cards on top of the powder. That is usually a bit less " messy" than handling balls of waxy lube, but not much! :hmm: I like the idea of having an OS card immediately behind the shot, so that the shot is pushed evenly, and all the shot releases evenly as it exits the barrel when fired. I see less stringing when I use OS cards behind the shot, than if I use cushion wads, or soft felt wads.
Roundball has written here about using 2 Ox-Yoke Felt wads, ONE SIZE Larger than his bore diameter( ie. if you shoot a 12 gauge, buy 10 gauge wads; if a 20 gauge, buy 14( if available) or 16 gauge felt wads) to put on top of his powder charges. The lube on the OX-Yoke wads is dry, so that the powder is not going to be fouled with grease/oil, during a hunting situation. This would be a quick and easy way to seat a load through a choked barrel, IMHO. By comparison, Iron Jim Rackham's technique allows you to carry ONLY ONE "wad", that is, OS Cards, each with a off-center hole punched into them at home before your hunt.
I go Jim's technique one better, IMO, of course, by simply using a greased cleaning patch I carry to the field, to lube the bore after seating the 2 OS cards on the shot load. In fact, I start the cards down the barrel, and then put the greased patch on the muzzle, and run the 2 cards down the barrel in front of the lubed patch, so that I grease the barrel as I seat those 2 cards on the shot. This saves steps in the field. I found that greasing the bore reduces if not eliminates leading of the bore by the shot as it exits the barrel when fired. It also protects the bore from rusting in the field, and seems to increase the number of shot I get in my patterns by reducing the flats that are rubbed into the shot pellets that are on the outside of the shot load. Putting the lube behind the shot charge, as Jim does, will not help either reduce shot deformation, nor stop leading of the bore.
So, :thumbsup: give these ideas your own testing, and let us all know what works best for you.
