Question on a Drilling shotgun Barrel

[don't]

I have a Drilling marked Gust:Meffert. It is an older hammer gun 16X16X9.3-72R. The bores are very nice for a gun built around the turn of the century. Being marked Nitro on both shotgun barrels I would think the gun was built between 1905 and 1915....

My question is this, The Right barrel is choke IM, left F+ and both bores are very nice with minor pitting, very minor in the right barrel. BUT as you look down the barrel there appears to be 3 grooves when looking from the breach, more when looking from the muzzle. I haven't had time to run a brush and patch down the barrel.

These are too evenly spaced to be done by accident or damage from cleaning. They appear to be "round bottom" like you find in old, handcut Muzzleloading Rifle Barrels.. Although there is little to NO twist to this "rifling".. I believe I had an older Hastings Mfg replacement barrel for a remington shotgun that was "similar" to this, it wasn't for shooting slugs but had something to do with shot patterns.

Does anyone know if this was done on German Drilling shotgun barrels and if so for what reason???

I will try to get some pictures up later this weekend...

Thanks in Advance...
Don

[sharps4590]

I can't speak as to the rifling you described but I do have a Jost & Diehl combination gun probably from the 1880's at the earliest and 1890's at the latest in 16 bore X 10.5 X 47R and the 16 bore barrel has straight rifling. The best I can describe mine is that there is 6 major lands, in height, and then between each two major lands is 6 lesser, shorter lands. It somewhat reminds me of MicroGroove riling. All are full length of the barrel and I'm fairly certain you're correct in that it had to do with the shot pattern and not slugs. My combination gun has a very tight, very long choke and I can't see trying to force a slug or round ball through it. I believe it was Axel who told me, when I asked about straight rifling, that in Germany it came and went as fashion dictated. I had heard of it but this combination gun was the first time I ever saw it anywhere. It's kinda neat to look at and makes for an interesting topic to discuss but in practice I believe all it does is catch lead and fouling.