Saw an old English hammer damascus double a few days ago, with a Jones underlever action. Nice condition, in 10 gauge.

What threw me was the straight rifling in the bores - looked just like typical Enfield rifling, but no twist. The gun had no rear sight, so I don't believe it was intended as a ball and shot gun.

Anyone know the history, or utility of such a design?

Boy, I've heard of that, but never in BP.

I know some people experimented with it in conjunction with modern wads. The idea being to keep the wad straight and stable until it left the muzzle and lost contact with the shot.

Doesn't seem to be an idea that lit the World on fire.

Reading the OP I didn't assume that the gun wasn't nitro poved.

Anyway, are you sure the rifling was straight, or might it have had a very slow twist, 1 in 60" or so?

Possibly to collect BP fouling?

Whatever, it was still made long before plastic shot cups.

Post that question on doublegunshop.com along with some details on the gun (make, etc.) and someone from England will chime in. That group knows a BUNCH about old double guns.

Man that's a LATE model gun for straight rifling; wonder if there's more too it. Any photos?

Chances are it is for ball and shot as it�s quite unlikely there is any constriction at the end of the barrel. If you look at the proofs on the under-side of the barrels, it will say �For ball and shot� or �not for ball�. If it doesn�t say either, then chances are there is no constriction and can be used with ball or shot. Understand that a shotgun that is for ball and shot doesn�t need sights as it�s intended mostly as a shotgun. Any idea who the manufacturer is?

take a gander, here:

http://www.collectorsfirearms.com/admin/product_details.php?itemID=16850

and edit to add, no twist, not even a quarter turn in their length, straight as an arrow.

Bingo! Allowed more shots before fouling made loading hard. Then it was thought that the grooves made in a spiral were longer, thus more area for bp fouling to go. Then it was found that this spiral grooves resulted in better accuracy. I read an article about this some time ago.

This is a breech loader, so that isn't the reason, or at least it isn't because of loading anyway.

Too bad this thread isn't about modern designs, say a 28 Gauge pistol with such slow twisted rifling that it didn't scatter the shot.

In my youth I loaded a bunch of steel ballbearings in a 16ga shell over fiberwads. Ended up with perfectly straight rifling and suprisingly they were evenly spaced around the bore.

oh, oppps

Good point.

There was a tremendous amount of experimentation during the 19th century, but going back into the 17th & 18th century when there was still some mystery to rifling, there were some interesting thoughts.

It was well known that along with being more accurate, rifled barrels would produce a �harder hitting� projectile and greater penetration. Many thought this was due to resistance in the bore which would build pressure before the projectile began moving, which certainly is true. So along those lines, there were some who thought rifling had more than just bullet stabilization to add. Straight bore rifling in the breech loading cartridge gun, while not unheard of, is still somewhat of an anomaly. At that late of a date chances are the gun maker is seeking something to differentiate his product from those of other makers. You need to know that the second half of the 19th century saw a massive amount of innovation and most gun makers had something unique about their guns that they would present as �better�; chances are that�s what this gun maker was trying to do. I�m aware of at least one Webley & Scott Premier Grade 10 bore hammer gun with straight rifling; I believe it was made in the early 1880�s; again, very late for straight rifling. Lest anyone think it was pure gimmick, consider that the Webley & Scott Premier Grade was, at that time, the most expensive shotgun in all of England; even more than the �bloody expensive� Boss Gun.

If I had to guess the straight rifling was to clear powder fouling for improved ball performance. Many guns of the early 1880�s and earlier didn�t have any choke boring, so while not nearly as accurate as a double rifle, it would not be uncommon for a gentleman to shoot ball from his shotgun for large game, and straight rifling would serve to minimize accuracy issues related to fouling. So a shotgun with �better� performance with ball ammo would be an �improvement� and something to differentiate a gun maker from other gun makers. Such a gun would give the owner a good compromise gun rather than having to buy a best shotgun and a best double rifle. So, THAT�s my guess.