I was firing from a rest with very little wind and over flags at 400 yards. I was continuing my load development trying to fine tune seating depth. With the bullet I was using jammed 5 I had had really good results with less than an inch of vertical at 400 with 6 different groups doing a powder charge test. I had settled on my charge weight and was tuning around a jam of 5.
I fired 3 or 4 sighters to warm up the barrel then fired a group with a different batch of brass I had to see if that mattered and I got a group I was expecting. Less than a half inch of vertical. Then I fired with the. Brass I had before when I was doing my previous testing. It had a vertically strung group with more than 2” of vertical. On the next group jamming 2k more it went right back to a flat line and all the groups around that were similar. So what can cause one crazy group like that when all the rest are similar?
This is jammed 5. Didn’t notice any wind changes.
This is jammed 7k. There was a wind shift here. With the flier being the first fired. I’m going to shoot a couple 10 shot groups with this load and if it holds up try it in the next match.
This is jammed 5k. Same load but a vertical string.
This is the same load the weekend before. 5 shots but in 15-20 mph winds. For load development I was pretty happy with this group. There was a strong left to right wind as I fired the first two. These are the lowest 2 on target. Then there was a let up and I fired the next three.
So basically the load worked about 8 out of 9 times. What causes the 1 vertically strung group and how do you prevent that from happening in a match?
I fired 3 or 4 sighters to warm up the barrel then fired a group with a different batch of brass I had to see if that mattered and I got a group I was expecting. Less than a half inch of vertical. Then I fired with the. Brass I had before when I was doing my previous testing. It had a vertically strung group with more than 2” of vertical. On the next group jamming 2k more it went right back to a flat line and all the groups around that were similar. So what can cause one crazy group like that when all the rest are similar?
This is jammed 5. Didn’t notice any wind changes.
This is jammed 7k. There was a wind shift here. With the flier being the first fired. I’m going to shoot a couple 10 shot groups with this load and if it holds up try it in the next match.
This is jammed 5k. Same load but a vertical string.
This is the same load the weekend before. 5 shots but in 15-20 mph winds. For load development I was pretty happy with this group. There was a strong left to right wind as I fired the first two. These are the lowest 2 on target. Then there was a let up and I fired the next three.
So basically the load worked about 8 out of 9 times. What causes the 1 vertically strung group and how do you prevent that from happening in a match?
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