I recently went to a Hipower course and the instructor had us load 7-8 different loads with various bullet OAL length's.Using an 80gr. bullet,for 500-600yds. But we shot them at 100yds. to "test" them. The next day we shot @ 600yds.there was NO WIND. I am a fairly good shot with an AR but I might as well have used a shotgun that day. The group was terrible. the OAL of my cartridge was 25 Thou off lands. My accuracy load that I have shot and it has gotten me many X's was about 5 thou off Lands. So does the OAL or powder have more to do with it? and can it be possible that a test load work at 100yds and then be sub MOA at 600? Thanks !
- Thread starter LARMIKE
- Start date
Re: Bullet length off lands question.
It is a mixture of many factors, but to keep things simple in your case, the powder or seating depth can affect your shot. It is hard to say which factor has more of an effect, but they both have to do with pressure and harmonic stability. Tune them both to get the right harmonics in your gun, and the bullet will exit straight. This is something you have to figure out by yourself though. The best way I know how is to perform the OCW test to figure out your rifle's optimum charge weight. After this is done, then screw around with the seating depths. I put up a post a couple of weeks ago about my experience with the OCW test:
http://snipershide.com/forum/ubbthreads....196#Post1736196
It is a mixture of many factors, but to keep things simple in your case, the powder or seating depth can affect your shot. It is hard to say which factor has more of an effect, but they both have to do with pressure and harmonic stability. Tune them both to get the right harmonics in your gun, and the bullet will exit straight. This is something you have to figure out by yourself though. The best way I know how is to perform the OCW test to figure out your rifle's optimum charge weight. After this is done, then screw around with the seating depths. I put up a post a couple of weeks ago about my experience with the OCW test:
http://snipershide.com/forum/ubbthreads....196#Post1736196
Re: Bullet length off lands question.
BTW, I just read your last question, but I am confused as to what it is you are asking. If you are asking if a load can shoot shitty at 100 and then perform well at 600, the answer is yes, especially with the 80 gr .224 diameter bullets. Zediker wrote a bunch about that in "the competitive AR15: the mouse that roared". It takes a while for that big ass bullet to quiet down, well past 100 yds. So there is no sense in shooting them unless you are shooting about 600, like you said.
BTW, I just read your last question, but I am confused as to what it is you are asking. If you are asking if a load can shoot shitty at 100 and then perform well at 600, the answer is yes, especially with the 80 gr .224 diameter bullets. Zediker wrote a bunch about that in "the competitive AR15: the mouse that roared". It takes a while for that big ass bullet to quiet down, well past 100 yds. So there is no sense in shooting them unless you are shooting about 600, like you said.
Re: Bullet length off lands question.
What I am looking for is can the bullet shoot a fuzzy group at 100 and then be judged to shoot tight at 600? Just because of seating depth? I knew that a long range bullet does not always shoot well at close range,Short range short bullet, Long range long bullet theory.
What I am looking for is can the bullet shoot a fuzzy group at 100 and then be judged to shoot tight at 600? Just because of seating depth? I knew that a long range bullet does not always shoot well at close range,Short range short bullet, Long range long bullet theory.
Re: Bullet length off lands question.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LARMIKE</div><div class="ubbcode-body">What I am looking for is can the bullet shoot a fuzzy group at 100 and then be judged to shoot tight at 600? Just because of seating depth? I knew that a long range bullet does not always shoot well at close range,Short range short bullet, Long range long bullet theory. </div></div>
Correct, Larmike. When you change the seating depth, it can effect the accuracy on a proven load. You basically have to develope the load over again. The node will be close to what you had, but it will need to be changed a little higher or lower in powder charge. I would also test the loads at 300 yards (or further on a calm day). The long 80 grain bullets may need to settle down some, and at 100 yards it may not tell you the true accuracy of the load.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LARMIKE</div><div class="ubbcode-body">What I am looking for is can the bullet shoot a fuzzy group at 100 and then be judged to shoot tight at 600? Just because of seating depth? I knew that a long range bullet does not always shoot well at close range,Short range short bullet, Long range long bullet theory. </div></div>
Correct, Larmike. When you change the seating depth, it can effect the accuracy on a proven load. You basically have to develope the load over again. The node will be close to what you had, but it will need to be changed a little higher or lower in powder charge. I would also test the loads at 300 yards (or further on a calm day). The long 80 grain bullets may need to settle down some, and at 100 yards it may not tell you the true accuracy of the load.
Re: Bullet length off lands question.
What is the twist rate of the barrel, I don't think you gave that?
What is the twist rate of the barrel, I don't think you gave that?
Re: Bullet length off lands question.
Thanks to all who answered, However, I am not looking for an answer,I know how to find the best accuracy for said rifle, What I am looking for is, Can it be possible to do this 100yd. test for shooting at 600yds. I would not test this at less than 300yds. The instructor had us test at 100 for our sweet spot accuracy do all load. I said hogwash and shot an OK group at 100 and could not keep them in a consistent group at 600 with NO WIND. I am looking for your actual experience with this.If you have ever been able to accomplish this seemingly impossibly feat. Thanks again, Chad did you ever test the .30 cal. bullets I sent you?? Mike
Thanks to all who answered, However, I am not looking for an answer,I know how to find the best accuracy for said rifle, What I am looking for is, Can it be possible to do this 100yd. test for shooting at 600yds. I would not test this at less than 300yds. The instructor had us test at 100 for our sweet spot accuracy do all load. I said hogwash and shot an OK group at 100 and could not keep them in a consistent group at 600 with NO WIND. I am looking for your actual experience with this.If you have ever been able to accomplish this seemingly impossibly feat. Thanks again, Chad did you ever test the .30 cal. bullets I sent you?? Mike
Re: Bullet length off lands question.
I don't see how that tweeking a load at 100 yds will insure preformance at long distance. It happens that a load that looks good at a 100 yds works at distance, have had them look not so good at 100 work great at long range, but I would have to prove it out at 300 yds and more. Most Long Range Shooters I know would not think of making that jump, hell they might look good at 300 and still go all over the place at 600 yds.
I shoot my loads at 100 yds for commom POI, then shoot those selected at 300 yds to varify, then back to 100yds to ajust seating on the selected load, then 300 and more if possible.
I don't see how that tweeking a load at 100 yds will insure preformance at long distance. It happens that a load that looks good at a 100 yds works at distance, have had them look not so good at 100 work great at long range, but I would have to prove it out at 300 yds and more. Most Long Range Shooters I know would not think of making that jump, hell they might look good at 300 and still go all over the place at 600 yds.
I shoot my loads at 100 yds for commom POI, then shoot those selected at 300 yds to varify, then back to 100yds to ajust seating on the selected load, then 300 and more if possible.
