Jug Choking ?

[wymberley]

11 minutes ago, Velocette said:

Stonepark, after you mentioned the possibility of reversed choke I checked the bores of the barrel set I used, to a distance of about 6" from the muzzle and found that the last 2" were about 1.5 thou larger that the bore. This was measured with a comparator gauge and was the same in both barrels. I then checked the other barrel set, which I haven't pattern tested yet and found that they were exact cylinder right to the muzzle. Clearly there is more patterning to be done with this barrel set.

Wymberley. I will try the Fiocchi cartridges again because in other guns I've found them to be quite reasonable and perhaps this reversed choke situation is giving a misleading result and the barrels are indeed guilty !

 

If you look at any 'recognised' table which Stonepark's is and focus on the figures for the more usual 40 yard pattern range, it's all very neat and tidy which is handy. Problem is is that there's a train of thought that the cylinder 40% is there to keep it so. The fact is that if a barrel is truly TC then achieving the 40% is extremely unlikely, if ever. Should the magic figure be achieved, then in all probability checking the barrel will reveal that there is the odd couple of thou' kicking around. Consequently, have faith in your own figures.

[Stonepark]

47 minutes ago, Velocette said:

Stonepark, after you mentioned the possibility of reversed choke I checked the bores of the barrel set I used, to a distance of about 6" from the muzzle and found that the last 2" were about 1.5 thou larger that the bore. This was measured with a comparator gauge and was the same in both barrels. I then checked the other barrel set, which I haven't pattern tested yet and found that they were exact cylinder right to the muzzle. Clearly there is more patterning to be done with this barrel set.

 

No worries, glad you are getting answers.