First, I've read some threads in this forum and found at least 2 threads that are related to my question of "first round flier" of AR. But none of them are specific on this topic (just related) and none of them gives a sure answer to this question. So I think it is OK to post a thread dedicate to this question.
My observation:
This is for my AR-15 with wylde chamber 1:7, target at 100 yard.
Last weekend, I did the following test:
1. Tested 4 different loads with 3 kinds of bullet: Hornady 75gr HPBT, SMK 77gr HPBT, SMK 69gr HPBT.
2. For each group, I loaded 3 rounds in a 20-round magazine. I closed the bolt for the first round by using the bolt catch. After the last round, bolt group will be stopped by the catch.
3. For two loads, I put two groups in one target: after I finished the first 3 rounds, I loaded the magazine and then immediately shot the second group. The time between the two 3-round groups is about 1 minute.
4. For one load, I put a 3-round group and a 2-round group together with approximately 1 minute loading time between them, to form a 5-round group.
5. After finishing a load (either one or two 3-round groups for that load), I waited about 5-10 minutes to start the next load's group.
Result is:
The first round of a load's group is always a flier around 7-8 clock direction. And this is true for all 4 loads.
The load that has two sub groups, the first round of the second group is NOT a flier. Only the first round of the first group is flier.
My thoughts about the observation:
1. In some other threads, people mentioned different way of closing the bolt for the first round may cause the “first round flier” but also they affirmed that by using the bolt catch to close the bolt, this problem will be gone. And this is exactly what I did. Also, for loads with two sub-groups, the first round of the second group is not a flier, and the second group employed the same way of closing the bolt for the first round. So it should not be a problem of how I closed the bolt.
2. Because I used 4 different loads with 3 different bullets, and this “first round flier” is true for all of them, it should not be a problem of loads.
3. I believe I have paid equal attention to the first round of a load as to the rest of the group, and for the 2nd group of a load, the first round is not a flier. I don’t think shooter is a problem of this (I am not a good shooter, and you can take this as: the first round is really bad, but the rest are just normally bad).
4. The only thing I think that may cause the problem is the long time of rest between loads. The time between first sub-group and second sub-group of a load is relatively short, and the first round of the second sub-group is not a flier. The time between two loads are long (as I check targets), and the barrel could cool down a lot. But I don’t know how this will affect the first round.
I’ve been searching for answers on the internet for a while. I found I am not the only one who has this problem. And I think this “first round flier” is a very important issue since a lot of times, you only have one shot to do the job (like hunting). If first round is always a flier, no matter how accurate and consistent the rest rounds are, it is useless. I found this forum has the most knowledgeable members so I hope people here can help to solve this mystery for me and for a lot of other people who have the same question.
Thanks.
My observation:
This is for my AR-15 with wylde chamber 1:7, target at 100 yard.
Last weekend, I did the following test:
1. Tested 4 different loads with 3 kinds of bullet: Hornady 75gr HPBT, SMK 77gr HPBT, SMK 69gr HPBT.
2. For each group, I loaded 3 rounds in a 20-round magazine. I closed the bolt for the first round by using the bolt catch. After the last round, bolt group will be stopped by the catch.
3. For two loads, I put two groups in one target: after I finished the first 3 rounds, I loaded the magazine and then immediately shot the second group. The time between the two 3-round groups is about 1 minute.
4. For one load, I put a 3-round group and a 2-round group together with approximately 1 minute loading time between them, to form a 5-round group.
5. After finishing a load (either one or two 3-round groups for that load), I waited about 5-10 minutes to start the next load's group.
Result is:
The first round of a load's group is always a flier around 7-8 clock direction. And this is true for all 4 loads.
The load that has two sub groups, the first round of the second group is NOT a flier. Only the first round of the first group is flier.
My thoughts about the observation:
1. In some other threads, people mentioned different way of closing the bolt for the first round may cause the “first round flier” but also they affirmed that by using the bolt catch to close the bolt, this problem will be gone. And this is exactly what I did. Also, for loads with two sub-groups, the first round of the second group is not a flier, and the second group employed the same way of closing the bolt for the first round. So it should not be a problem of how I closed the bolt.
2. Because I used 4 different loads with 3 different bullets, and this “first round flier” is true for all of them, it should not be a problem of loads.
3. I believe I have paid equal attention to the first round of a load as to the rest of the group, and for the 2nd group of a load, the first round is not a flier. I don’t think shooter is a problem of this (I am not a good shooter, and you can take this as: the first round is really bad, but the rest are just normally bad).
4. The only thing I think that may cause the problem is the long time of rest between loads. The time between first sub-group and second sub-group of a load is relatively short, and the first round of the second sub-group is not a flier. The time between two loads are long (as I check targets), and the barrel could cool down a lot. But I don’t know how this will affect the first round.
I’ve been searching for answers on the internet for a while. I found I am not the only one who has this problem. And I think this “first round flier” is a very important issue since a lot of times, you only have one shot to do the job (like hunting). If first round is always a flier, no matter how accurate and consistent the rest rounds are, it is useless. I found this forum has the most knowledgeable members so I hope people here can help to solve this mystery for me and for a lot of other people who have the same question.
Thanks.