Improved cylinder?

[Leadchunker]

Anyone ever shot tss through 16 ga improved cylinder barrel jus curious how it patterned

[Spring Creek Calls]

I would think IC may be a bit open, great for up close work though. Improved modified or full would probably work better. If your gun is fixed choke IC, a large sheet of paper and your preferred load will tell the tale.

[Leadchunker]

I don't have the gun yet just ran across a good deal on a Ithaca 37 featherweight just wanting to check 16 gauge off the list not been able to find modified or a full choke barrel for a reasonable price

[crow]

You might get there with one of Federal tss flight control wads, have seen fairly impressive buckshot patterns out of imp. cyl. bore with them.

I messed with a blackpowder shotshell imp.cyl.  choked gun very thoroughly trying to get to 40yds, could wall paper my house and yours with the patterns. just barely got there with tss.
But the flight control wads don't function as designed with blackpowder

I don't think you'll get to 40 with regular wads

[YoungGobbler]

Improved cylinder will open wide in short distance. At 20 yards you'll have a few pellets in head/neck area... It would only make a very interesting pattern at 10-15 yards, and that's very close!! Would be a better choke for pheasant/rabbit hunting.

[Super Fox]

In older guns you would mostly be better off with FC or MOD, but it depends on the gun
and the effectiveness of the shot column wad. The locked wad concept like employed by Winchester's Long Beard shell does work.
This is why knowing patterns with different lead, bismuth and tss in different guns is critical.

That said, I have used HeviShot 3 in #4 shot in both a 3 in LC Smith and a Winchester Heavy Duck Model 12 3 in.
The Smith had a slightly tighter pattern, but the bismuth H-S 4s both did in  2  (two) gobblers with different shotguns at about 38-42 yards distance.