Semi auto and solid slug

[bogtrotter]

Grooves but not rifled. Obviously you didn't use the right type of slug e.g. Benekke which are designed to pass through all types of choke as it says in the link. Some types of slug such as the sabot type are really intended for use through rifled barrels while Brenekke type which are more popular in Europe as designed to be fired through conventional shotguns.


Edit.
I was in a rush when I wrote the above last night so didn’t put it quite right.
You say that the slug has left grooves at the choke of your Laurona shotgun bogtrotter are you mistaking streaks of lead for grooves? I can’t believe a soft lead slug will gouge a steel barrel. If the slug did not compress on the fins and you drove the slug through a tight choke surely you would have bulged the barrel but it is extremely unlikely that this would be in the form of individual ridges or gouges. Yes I know there are cases of over rifling on thin barrelled express rifles when the original Barnes type copper bullets have been pushed down the bore at high pressure and left a ridges in the form of the rifling on the outside of the barrels, but in the case of a shotgun the result is going to be a bulged barrel if there is a problem.

As I said there is a slight bulging of the barrel , you can feel it if you run your fingers along the barrel but you have to look very close to see it.

No I am not mistaking lead fouling for grooves the barrel is most definitely gouged and deep would say very close to coming through.

The gouging is in a spiral manner, which is why I said rifled the barrel in my original post as that is what it looks like very crude rifling

 

[bobt]

we tested the theory of Hollywood cops hiding behind car doors!

shot a Renault Fuego broadside.
It went through the drivers door, drivers seat, handbrake handle, passenger seat, passenger door liner and punched a bulge into the skin about 2" deep.

next one went through the front wing into the engine, smashed the crank case and destroyed itself somewhere between piston and crank, taking a con rod with it.

nasty

We had a keeper like that once too

 

[saddler]

Quite simply, while the slug may be softer than the barrel it has torn quite deep grooves into the barrel where it is chocked so much so the gun is now unsafe to use.

I should say rifled was just a figure of speech, the barrel is also slightly bulged you cannot really see it but you can feel it if you run your fingers down the barrel.

Can you post photos of the damage?

 

[bogtrotter]

Can you post photos of the damage?

Don't know how I could post photo of damage, as its inside the barrel, I could try I suppose but dont know what sort of image I will get trying to photograph the inside of a barrel
there is a slight bulging of the barrel but as I said earlier you can hardly see it with the naked eye so you won't see it in a photo.