Before you spend money having the barrels jug choked, try loading your shot into a paper cup that you make yourself. You may have to experiment with different weights of paper to find what gives the desirable pattern in your gun. I have experimented with paper that ranged from printer paper to as heavy as index card stock.
The way to make your cups is to cut your paper in the shape of a + with the legs of the + being the width of your bore. The intersection of the + should be just a slight bit smaller than the bore itself so that it will easily slip into the bore. The length of the legs will be just long enough to enclose your chosen load. When the shot is poured into the cup, it should fill up to the ends of the cup legs. If the legs extend beyond the shot charge, cut them off level with the shot. Then make the rest of your paper cup legs so that they do not extend beyond the shot charge.
To load this shot cup, you put in your powder and then insert your OP wad just far enough into the muzzle so that you can sit the cup on the wad. Center the + on your muzzle and start it down the bore until the legs are just below the muzzle. As you insert your paper + into the muzzle, the legs will fold up to form the cup. The wad will support the cup as you fill it and not allow it to slide down the bore as soon as you start to pour your shot into it. You add the shot to the cup and then use your rod to seat the filled shot cup and OP wad down onto the powder. Add your OS card as usual.
I found that you can glue your OP wad onto the intersection of your paper + with a tiny dab of glue. This allows you to simply pick out a cup from your bag and insert it into your bore without having to bother with first putting the OP wad into the bore. It is all one unit. It was something that worked quite well for me. It has the added advantage of keeping the OP wad with the cup as it exits from the bore. The legs of the cup open and act like a parachute to cause the OP wad and paper cup to slow immediately as they exit from the muzzle and prevent either from passing through your shot string to cause a doughnut pattern.
Another advantage of the paper cup is that, when properly formed, the shot will never touch the inside of your bore. Therefore, you eliminate any leading problem in your bore.
It's an idea worth trying. :thumbsup:
If this doesn't give you the pattern that you want and you want to tighten it up even more, just send me a PM and I can tell you how to make a different paper cup that will tighten up your pattern.
