we noticed an immediate improvement by putting a overshot card over the cushion wad before putting in the powder. I believe the theory is it helps the wad from become a temporary slug. If you pick up a cushion wad without it you'll notice where the bb's have imprinted on it. Dads old double really tightened up, mine did just a little.
In my 10, I ran all overshot cards and a 1/8 nitro in the mod barrel and the standard over cushion over shot bb's and overshot again. its ok out to 20...with the double I rarely use the cyl bore.
I did try some tubes, something to consider. The plastic shotcups are a royal ugly mess imho! I tinkered around cutting them down cutting wings etc etc...initially they slugged...quite impressive btw. I didnt try post it notes rolled into a shotcup. Ran out of time.
The two fowlers I've been building for hmm...WAAAy too long I plan on jug choking. Something to consider if you have someone around who can do it. There was a fella in Iowa last I heard that would for a modest fee.
Lastly I went with 5's. 6's leave a heavier pattern, 4's are more powerful farther out. 30 is about all you're likely going to get without tubes/jug choking or shotcupping it. 20-25 would be a more likely goal imho. I have never liked 6's. They have a helluva pattern, but I've seen too many birds rolled and not killed over the years to stay clear of them. The 5's seem to be a nice inbetween of pattern and power. I believe the article BB was referring too by Starr talked about this. I ran copper plated 5's. Would like to try some of the nickle plated 5's at some point. And the same loads worked great on roosters also.
in my 10, I'm running 105 grs RS with 1 1/2 ounce of 5's. powder, os, 1/8 nitro, shot, os in the mod, and the tradional load again with 105gr rs under 1 1/2 in the cyle bore with the added os card on the cushion wad. Didnt matter how reduced I went I couldnt get it any tighter in the cyl barrel. I didnt try 1f. Right now I'm hoping I'll have a jug of RS waiting on me in the midwest and another on the east coast or it may turn into a trout trip LOL!
if you're blowing holes slow it down till it tightens up. We burned a tub of powder in the double getting these loads. I wish it wasnt so blasted cold when I get the itch to go out testing again LOL! come summer its 5th gear wide open bear hunting salmon fishing, right into fall hunting season and back to 1st gear for winter
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