Can anyone kindly advise on design dimensions of these chokes please?
I have a multichoke B525 sporter 1 and was thinking of obtaining some additional chokes for the skeet range. It was proofed at 18.7mm (0.736") both tubes, and still measures that. So some degree of over/back boring present. I have a standard set of Browning chokes at 1/4, 1/2, 3/4 and full UK sizing.
On inspection and with chokes installed, i note a distinct step at the junction of the breech end of the chokes and the muzzle end of the bores (pre-choke) All 4 chokes measure the same 0.750" bore at the breech end and taper according to the particular choke size. Please see attached NTS drawing.
So to my queries, the difference in bore diameter between each end of the chokes seem to conform approx to the expected constriction for each choke size ie 10, 20, 30 & 40 thou, however would the previously mentioned step not negate this? or does the conventional method of choke measuring not apply to invector plus chokes with over-bored tubes and the choke is determined purely on pellet count % in the circle at set yards?
I have not pattern tested any of the chokes, but would like to know if the step should be there by design?
I usually shoot antique muzzle loaders and early breech loading hammer guns, so removable chokes are new to me!
Many thanks.
