Alright fellas. Sorry for the delays, but they were out of my hands. Went to the range a week ago yesterday and they had it closed for the summer games. This week I got the opportunity to go yesterday morning at about 6:00am. The conditions were not perfect. However, they were good enough to get the results I needed to answer some questions.
In an earlier post I had mentioned that I loaded up 7 new four shot groups. to take and try. Of these several loads, 5 were were loaded with 72 grains. I did this because I would agree that My rifle likes them tamed down just a bit. The other 2 loads were loaded at the 73.5 grains from one of my other loads. Only this time I switched the Primers to Remington large rifle Magnums. I loaded each of these two loads with differing seat depths. The results were interesting to say the least.
First. The two loads at 73.5 grains. Remington Primers performed very similar to the CCI in the loads that had the same seat depths. In the load with Remington primers and a longer COAL. The group remained roughly the same size, but went from flat horizontal into a triangular pattern. It would be safe to conclude that my rifle did not like this charge weight as much as the lighter loads.
Second. The five loads at 72 grains. These loads had varying seat depths from 3.340 to 3.410. A total of .070 variation.
The loads were loaded at these lengths.
3.340"
3.355"
3.375"
3.395"
3.410"
The load of 3.340" measured roughly the same as the picture above. They also created a similar pattern on the paper
The load of 3.355" closed up to about 5/8 of an inch and the shot pattern was straight horizontal. It looked alike a stringed hole in a horizontal pattern.
The load of 3.375" opened up dramatically! It measured at 1 1/8 of an inch and was in a triangular type pattern.
The loads measuring 3.395" and 3.410" followed suite. They opened up a little more respectively the longer the COAL was. and they formed a similar pattern.
As mentioned above. The conditions were not perfect by any means. I was dealing with a wind blowing directly from the target to my shooting position at around 5 mph. I was not happy with this but knew it was much better than a cross wind. The Humidity I would venture to be 100% as it had rained all night. Fortunately it had stopped for a few hours in the morning to allow me to shoot. It was cold and wet though. The ability for a person to shoot is lessened in these circumstances, but I feel I got the data needed.
The rifle was clean and the shots were fired under similarly to those pictured above. My barrel was allowed to cool completely between groups.
Sorry for the lack of target pictures. They were compromised on the way home with rainfall and the wind in the back of the truck. apparently I was not smart enough to get them off the box for the ride home. I would have loved to have had them to share
Conclusion. I was very near the optimum COAL with my original loading. However, it wash worth the extra research and development to obtain the best COAL for my rifle. I am a fair length off of the lands. I took a rifle that would not shoot under 2 inches with factory loads is now shooting under .75 MOA! Mission accomplished. I am excited to try these on some game.
Thanks for your interest and please share your thoughts or ask any questions you may have.
Mike Twitchell