Load development question...
Posted: Sun Jan 13, 2008 10:40 am
I'm working on loads for a Ruger No 1AB. I worked up loads using IMR4895 with a 32gr Sierra BK starting at 26.0 through 28.2 grains, at .2 grain increments. I loaded 3 of each load, so I fired 3-shot groups with each load. I shot off a rest at 150 yards.
The hotter loads (28.0, 28.2) both resulted in groups about 2.75" (at 150 yrds). The remaining loads grouped better (around 1.5) but none really looked better than the other except for three loads (26.0, 26.8 and 27.0) which produced a similar pattern: the first 2 shots were practically in the same hole, the third was off by +/- 1".
What do you think is going on?
1) barrel getting hot? I fired the three shots without cooling the barrel and the lighter No. 1 barrel was warming up quickly. I was firing strings of 12 shots (4 targets, 3 shots per) and letting the barrel cool for around 20 minutes before starting the next series. I started with the 26.0 load and so after a fouling shot my second and third shot went into one hole.
2) operator error (IMO most likely)? I'm new to this, and can see the bullet holes through my scope. So each time I fired the third shots I could see the groups of the first two.
3) load not right? Do I need to start over?
What do you think?
The hotter loads (28.0, 28.2) both resulted in groups about 2.75" (at 150 yrds). The remaining loads grouped better (around 1.5) but none really looked better than the other except for three loads (26.0, 26.8 and 27.0) which produced a similar pattern: the first 2 shots were practically in the same hole, the third was off by +/- 1".
What do you think is going on?
1) barrel getting hot? I fired the three shots without cooling the barrel and the lighter No. 1 barrel was warming up quickly. I was firing strings of 12 shots (4 targets, 3 shots per) and letting the barrel cool for around 20 minutes before starting the next series. I started with the 26.0 load and so after a fouling shot my second and third shot went into one hole.
2) operator error (IMO most likely)? I'm new to this, and can see the bullet holes through my scope. So each time I fired the third shots I could see the groups of the first two.
3) load not right? Do I need to start over?
What do you think?