1830's Muzzle Loading Black Powder Dbl. Bbl. Shotgun

mfg. by ----------R.& W.C. Biddle (Robert & William Candy Biddle)
mfg. date ------- Circa 1830-1840 Philadelphia, PA
bore gauge ----- (5 or 6) Five or six gauge
barrels ---------- 30" Long "London Real Twist" Damascus Steel
lock style ------- Nipple & Percussion Cap, Back Action
engraved on ---- Locks - Bbl. - Tang - Trigger Guard - Hammers - Butt Plate

I bought this monster a few years ago at a Md. swap meet. What impressed me was the bore size a whopping 1" in dia. The gun is massive and must weigh at least 12 pounds. It is in excellent condition and was taken very good care of. With all of the engraving, I recon it was a pricy gun for the time.
Somebody told me that is a punt gun, used for water fowl in the Md. marshes.
I have my doubts about that because the punt guns that I saw on the internet have really long barrels to reach across the water. This has 30" barrels and it doesn't look as if they were cut off sometime in the past.
A friend said that he wanted to shoot it. I certainly don't want to shoot this monster, and I am a little concerned about the liability factor in letting anyone else shoot it.
Any information that anyone may have on this Muzzle loading 4 gauge would be greatly appreciated.
PS. your darn tooting, I'm scared to fire off this monster!.....