Choke size for lee 1oz slug

[Saxmann10]

What’s is recommended for a choke for a lee 1oz slug
IM - MOD or a rifled choke.

[CastingFool]

As far as I know, Improved cylinder is usually best. The less the slug is deformed, the better the accuracy.

[EMC45]

I shoot mine out of Cyl or Imp Cyl. They do well. A good solid 50 yard group.

[Ginsing]

Skeet choke or IC choke with thin petal wads. Cylinder choke tube with thicker petals.
I have shot them through L.M. and modified choke tubes as well but accuracy wasn't as good.
You might have to try different chokes to see what works best for your shotgun. My 870 shot best with skeet choke and my mossberg 590 shoots great with I.C.
With my minimal testing with a rifled tube I didn't notice much difference. Some people have better results.
I just prefer a smoothbore because of its versatility so most of my testing has been done with a smoothbore

[Saxmann10]

I have a modified and will pick up a ic and try both

[Ginsing]

What wad are you using?

[Saxmann10]

Wad is from ballistic product L078 lightning same as the pt1215

[Hogtamer]

Would say No modified unles dead soft lead.

[longbow]

One day I'd like to take an old shotgun with a full choke and see what it will take.

My bet is that the Lee or Lyman wad slugs will make it through without choke damage because both are under muzzle diameter so even if cast from hard alloy the plastic wad should extrude. Plus hard or not the Lee slug is a typical Foster thin walled shape so should swage down and the Lyman has small bearing area so the wad petals should extrude or shear.

Screw in chokes may be a bit more fragile than a bored/fixed choke as they are amazingly thin... or at least the one I bought to rifle is amazingly thin and the remaining barrel wall must also be as amazingly thin.

Not saying I'd be holding the gun when the trigger is pulled! Safety first and rightly so. I'd take the old gun and tie it to a tire or similar and pull the trigger with a string from behind a shield just in case. I suspect that the gun would come through alright but that remains to be seen. A steady diet of hard slugs through a tight choke may lead to cracking over time so not something I'd recommend even if a few shots didn't destroy the choke/barrel.

However, accuracy with anything beyond I/C is likely questionable as wad petal failure would likely be in play.

So back to the question, I'm with Hogtamer on I/C choke for anything not dead soft lead.

Longbow