This year I will be hunting exclusively with cast bullets. I expect to be firing some hunting shots from a clean barrel. It will be useful to know the likely clean barrel POI as well as the “fouled” POI of my rifle.
A check of 18 five shot 100 metre groups for my Savage 99 .30-30 reveals six with the fouling shot within the group, six with fouler on the same elevation but a little left or right, and six with fouler above the edge of the group by a half to two minutes. This was across five different lubes, and two powders, with no standouts. There was no consistent pattern of fouler MV being above or below group average.
Larry Gibson’s big high velocity lube test (14 lubes) revealed two that threw the first shot – one by 9” at 100 yards and one right off the paper. This would completely invalidate those lubes for my hunting application. Conversely, two other lubes in Larry’s test put the first shot to group.
My bullet is #U321297HP 175 gns sized to .312”, about 11% non-lead and a little harder than #2, lubed with Lyman Orange Magic. Load is 33 gns 748, velocity 2180 fps. The last five shot group with this load went 1.99” at 100 m, with the fouler in the group.
This morning I put the clean barrel story to the test. The plan was to fire one fouler, shoot a five shot group, then another five shot group cleaning before each shot. Cleaning comprises two up and down passes with a phosphor-bronze brush and Ed’s Red, then patch dry.
As it happened, the fouler of the day was from a barrel that had been cleaned, wiped dry, and not fired for almost three months. That shot went nearly 5” high of aim, and over 3” high of the subsequent group centre. This is at odds with the fouler POIs from previous recorded groups.
The group itself was an unspectacular 3.46”, POI 1.6” high, velocity 2184 fps SD 15.
Then came the “clean” shots, each from a barrel freshly cleaned and wiped “dry” with two patches. Group was a very interesting 1.67” (1.5 minutes), and POI high 0.6”, a little lower than the main group. Velocity was 2173 fps and SD 16.
Every part of this result was useful information.
For the initial shot, I can speculate that the barrel was well and truly dry after sitting unused for three months. At any other time of the year I would be using the rifle more or less continuously, so my other groups may not have encountered this situation. This might explain the high shot this time being "out of character".
Lesson #1 is to freshen up the bore (Ed’s Red) before going afield.
Lesson #2 is that from a freshly cleaned barrel I can perhaps now expect reliable POI for the first shot.
Lesson #3 was that I had expected the group of “foulers” to be larger than the regular group, but the reverse was true. How come? I wonder what a sniff of ATF in the lube might achieve?
I would be interested to hear of others’ experiences in managing clean barrel POI for hunting. Or do you have a lube or a bore process that reliably sends the clean barrel shot to group?
You are only as good as your library.