I posted a link this test
http://www.uplandjournal.com/cgi-bin/iko...ler+and+pattern in the past. It is a fairly elaborate pattern test experiment that he undertook. STS and Nitromag were used 2-3/4" 7/8, 1 oz, and 3" 1-1/4 oz. An Ithaca 37 barrel was used because it has lots of metal to accommodate being opened to 0.630" in 0.005" steps starting at 0.615". 2" forcing cone set at start and amount of constriction was kept to 0.025" (20 g full?). The patterns seem sub par at 0.615" barely IC, and seemed to arrive at full choke performance at 0.625" for the 7/8 and 1 oz loads. At 0.630" it patterned full with the 3" Nitro-Mags in #6 and #4 shot.
He said the wad was hard to push through 0.615" and the wad was damaged by the effort, which seems abnormal; those shells in that barrel might have given pressure spikes. Other shells and wads may have worked better at the 0.615" original diameter.
Says the patterns became more evenly spaced, denser, and less patchy as the bore was opened. Larger shot sizes patterned best at the largest overbore tested, 0.630". The results seem to change consistently as the bore was opened.
I only know what he posted. Some one may have an 0.610 20g that patterns great.
Last edited by J. Hall; 06/28/07 05:34 PM.
