Just curious....When a SXS is marked "not for ball" is it because the choke is too tight, the barrels are not capable of handling the pressure or the action is too weak?

Thanks,
WBLDon

It's my uderstanding that was the first way of marking a choked gun...back then balls or slugs weren't supposed to be shot through a choked barrel.

I'm sure mr.TEd will be along in a minute to correct me.

Just saying.

Yes, a way to denote constriction. But I guess the questions would be better phrased as "When a scattergun is marked "Not For Ball", etc.....

Not for Ball
Non Pour Balle
Nem Golyonak
Jen Pro Broky
Nicht Für Kugel

it meant that the tube experienced proof with shot and not a solid projectile. The Austrians were the only ones that continued to subject their scattergun tubes to a solid projectile w/ "windage" while all other proof facilities employed shot.

Cheers,

Raimey
rse

"Nicht Für Kugel, Nem Golyonak, Jen Pro Broky just notes constriction and is comparable to Crown over W. In the Austro-Hungarian empire during preliminary proof there was no distinction between smoothbore & rifled tubes as both were fed ball or cylinder, with an allowed clearance of up to 0.5mm. Then all tubes were exposed to some 10 ATM test with a pump apparatus to check for failures. Next rifled tubes were fed a diet of 2 balls or cylinders, what better way to double the weight, while scattergun tubes received a load of 1 1/2 times their shot charge. Most sources give the 1st & 2nd proof for scatterguns was with a solid projectile while the 3rd proof, which could also be an inspection, was with shot. On a tube with choke the diameter was measured forward of the chamber while cylinder tubes had their diameter measured at the muzzle."

http://www.doublegunshop.com/forums/ubbt...true#Post292152

Cheers,

Raimey
rse

The Belgian proof house used Non Pour Balle 1878-1897; "Choke" thereafter, to indicate constriction > .2 mm or about .008" at the muzzle

"Not for Ball" was also replaced by the proofmark "Choke" on British doubles. As with the Belgian example above, "choke" could be relatively little choke.

Given the same weight & same powder charge, a load of shot will produce a higher pressure than will the round ball This is due to the increased friction of the shot charge. Prior to choke boring it had been standard practice when shooting a round ball from a shotgun to use a fairly close fitting ball. If this size ball was fired through a choked gun it would have a diameter larger than the diameter of the choke & likely result would be a split muzzle.

A round ball can be fired from a choked gun with complete safety, As Long as the diameter of the ball is smaller than the choke. Accuracy may suffer but no harm will come to either the gun or the shooter, given Proper Loading.

The misunderstanding of this was one of the major reasons for changing the marks from "Not For Ball" to "Choke" As I recall most proof laws required one of these marks, depending upon time frame, on any gun having 0.2mm (0.008") of choke or more. It was I believe optional on a gun with any lesser amount of choke. A cylindder bore was of course unmarked.

Thanks very much folks... This answers my questions....

WBLDon

Miller:

That would be 0.2cm or 2 mm.

Cheers,

Raimey
rse

2mm is nearly 0.080 inches
Not likely.......

Miller is correct; .2 mm = 0.00787"
I corrected my post.

I guess you just got caught up in your copy and pasting....

That is correct under British rules of proof. Guns with a minimum of .008" constriction had to be marked Choke. But the person submitting the gun for proof could request that it be marked Choke if it had as little as .004" constriction.

Miller that is 0.2mm.....


Cheers,

Raimey
rse

Yes, 1 mm = 0.3937" or under the "Old" standard a full choke. I normally use the reciprocal of 1" = 254mm so 0.2 /25.4 = 0.00787 or rounded to three decimal places 0.008".