Ok today I shot a little bit down by the river on the sandbar. I shot about 25 rounds. My load is 44g of varget 175 SMK winchester cases federal match primers, COAL of 2.930 thats about .015 off my lands. 2564 fps. I had my rounds divided into two sections tumbled and non tumbled.Load data was the exact same! The reason for this is I wanted to see if there was a accuracy improvement over clean brass. What I seen shocked me and im still puzzled! I shot into 3 shot groups and the non tumbled brass with my load shot from 0.190-0.326 at 100 yards.Safe to say my average is around .25 moa give or take a little. The brass that i tumbled that has the absolute same load grouped 0.542-0.711. All the cases was trimmed to the same length and preped the same. I ran the one set of cases through the tumbler AFTER they were resized, trimmed, reamed ect. I made sure I got all of the stuff out of the case lol so thats not it. I did notice that the tumbler only cleaned the outside of the cases, the inside was still black. Anyone know whats going on?
Range Report WHY DID MY GROUP OPEN UP?
- Thread starter stapletonb08.1740
- Start date
Re: WHY DID MY GROUP OPEN UP?
Re: WHY DID MY GROUP OPEN UP?
Just got lucky with the one grouping and unlucky with the other? Shouldn't have made any difference whether clean or not. If having clean brass was a necessity I'd never hit anything.
Some guns shoot better not being cleaned, it appears your gun may like brass that hasn't been cleaned.
Topstrap
Just got lucky with the one grouping and unlucky with the other? Shouldn't have made any difference whether clean or not. If having clean brass was a necessity I'd never hit anything.
Some guns shoot better not being cleaned, it appears your gun may like brass that hasn't been cleaned.
Topstrap
Re: WHY DID MY GROUP OPEN UP?
Well i thought it was luck the first time but 3 groups around .25 moa and 6 groups of .60 moa tell a diff story. The wind was blowing a little bit but it really seems like something was different. I really dont know
Well i thought it was luck the first time but 3 groups around .25 moa and 6 groups of .60 moa tell a diff story. The wind was blowing a little bit but it really seems like something was different. I really dont know
Re: WHY DID MY GROUP OPEN UP?
Tumblers I've found clean the outside and leave a residue on the inside. That's why I switched from a tumbler to a sonic cleaner. Doesn't pretty it up the way a tumbler does but it does clean the inside of the case, which I believe may have an affect on case capacity.
Now, whether or not that is what caused your groups to open up or not? I doubt it, but atleast 1/2 of your question got answered . Are you sure all the media was removed from tje brass? When I was using a tumbler there was a couple of times when some media didn't get removed entirely from the brass and that will definately have an affect on you case capacity and hence your group size as well.
Just a thought.
Tumblers I've found clean the outside and leave a residue on the inside. That's why I switched from a tumbler to a sonic cleaner. Doesn't pretty it up the way a tumbler does but it does clean the inside of the case, which I believe may have an affect on case capacity.
Now, whether or not that is what caused your groups to open up or not? I doubt it, but atleast 1/2 of your question got answered
Just a thought.
Re: WHY DID MY GROUP OPEN UP?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Kevlars</div><div class="ubbcode-body">Just a FYI. Stainless steel media cleans inside and out. I moved away from the sonic cleaners. </div></div>
Good to know. Might have to give that a try. Thanks for the info.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Kevlars</div><div class="ubbcode-body">Just a FYI. Stainless steel media cleans inside and out. I moved away from the sonic cleaners. </div></div>
Good to know. Might have to give that a try. Thanks for the info.
Re: WHY DID MY GROUP OPEN UP?
Were you shooting the tumbled groups with a really hot barrel? Certainly as that barrel heats up, you are going to see your groups open up, all else equal. How much it opens up is a function of your barrel and how hot it is...
Were you shooting the tumbled groups with a really hot barrel? Certainly as that barrel heats up, you are going to see your groups open up, all else equal. How much it opens up is a function of your barrel and how hot it is...
Re: WHY DID MY GROUP OPEN UP?
nope
nope
Re: WHY DID MY GROUP OPEN UP?
No i shot in 3 round groups then let the barrel cool for a little while. I shot 3 tumbled then 3 non then 3 tumbled that was the order i did it it.
No i shot in 3 round groups then let the barrel cool for a little while. I shot 3 tumbled then 3 non then 3 tumbled that was the order i did it it.
Re: WHY DID MY GROUP OPEN UP?
My brass is in very good shape! Its been shot about 4 or 5 times. Since i have a extremly long COAL there isnt much pressure on the neck. I have not annealed the brass. I have heard a lot of people say its not really needed.
My brass is in very good shape! Its been shot about 4 or 5 times. Since i have a extremly long COAL there isnt much pressure on the neck. I have not annealed the brass. I have heard a lot of people say its not really needed.
Re: WHY DID MY GROUP OPEN UP?
The more you work the brass, the harder it gets. The harder it gets, the more the neck tension changes.
Could the bigger groups be wind, or position, or caffine, or temperature, or problems at home, or thinking of a girl you saw on the way to the range........? The list goes on....
The more you work the brass, the harder it gets. The harder it gets, the more the neck tension changes.
Could the bigger groups be wind, or position, or caffine, or temperature, or problems at home, or thinking of a girl you saw on the way to the range........? The list goes on....
Re: WHY DID MY GROUP OPEN UP?
3 shot group doesn't mean much anyways, do the dot drill, stop chasing groups.
3 shot group doesn't mean much anyways, do the dot drill, stop chasing groups.
Re: WHY DID MY GROUP OPEN UP?
Well the wind was blowing pretty good, and it was pissing me off! It was blowing in a 12:00-2:00 direction about 9-15 mph. I also shot that same day at 250 yards and averaged .60 moa with the brass that was tumbled. My windage was 1 moa at that distance.
Well the wind was blowing pretty good, and it was pissing me off! It was blowing in a 12:00-2:00 direction about 9-15 mph. I also shot that same day at 250 yards and averaged .60 moa with the brass that was tumbled. My windage was 1 moa at that distance.
Re: WHY DID MY GROUP OPEN UP?
What exactly is the dot drill?
What exactly is the dot drill?
Re: WHY DID MY GROUP OPEN UP?
Here is a link to a discussion/thread about the dot drill. It is not the original thread from Lowlight describing this drill, but it has links so you can download a printable version of the target. Although there is nothing at all wrong with shooting groups, this drill is is a different approach to training in that you shoot one round at each dot (rather than shooting groups) and you really need to focus and use solid fundamentals to make each shot count. It is NOT easy, but is a lot of fun and really can help with hold, trigger control, etc.
http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=973070&page=1
http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=2626362#Post2626362
Here is a link to a discussion/thread about the dot drill. It is not the original thread from Lowlight describing this drill, but it has links so you can download a printable version of the target. Although there is nothing at all wrong with shooting groups, this drill is is a different approach to training in that you shoot one round at each dot (rather than shooting groups) and you really need to focus and use solid fundamentals to make each shot count. It is NOT easy, but is a lot of fun and really can help with hold, trigger control, etc.
http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=973070&page=1
http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=2626362#Post2626362
Re: WHY DID MY GROUP OPEN UP?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: gstaylorg</div><div class="ubbcode-body">Here is a link to a discussion/thread about the dot drill. It is not the original thread from Lowlight describing this drill, but it has links so you can download a printable version of the target. Although there is nothing at all wrong with shooting groups, this drill is is a different approach to training in that you shoot one round at each dot (rather than shooting groups) and you really need to focus and use solid fundamentals to make each shot count. It is NOT easy, but is a lot of fun and really can help with hold, trigger control, etc. </div></div>
Link?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: gstaylorg</div><div class="ubbcode-body">Here is a link to a discussion/thread about the dot drill. It is not the original thread from Lowlight describing this drill, but it has links so you can download a printable version of the target. Although there is nothing at all wrong with shooting groups, this drill is is a different approach to training in that you shoot one round at each dot (rather than shooting groups) and you really need to focus and use solid fundamentals to make each shot count. It is NOT easy, but is a lot of fun and really can help with hold, trigger control, etc. </div></div>
Link?
Re: WHY DID MY GROUP OPEN UP?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: nfoley</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: gstaylorg</div><div class="ubbcode-body">Here is a link to a discussion/thread about the dot drill. It is not the original thread from Lowlight describing this drill, but it has links so you can download a printable version of the target. Although there is nothing at all wrong with shooting groups, this drill is is a different approach to training in that you shoot one round at each dot (rather than shooting groups) and you really need to focus and use solid fundamentals to make each shot count. It is NOT easy, but is a lot of fun and really can help with hold, trigger control, etc. </div></div>
Link? </div></div>
Here you go. Read through it, you'll get the picture. Good luck.
http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=2470674
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: nfoley</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: gstaylorg</div><div class="ubbcode-body">Here is a link to a discussion/thread about the dot drill. It is not the original thread from Lowlight describing this drill, but it has links so you can download a printable version of the target. Although there is nothing at all wrong with shooting groups, this drill is is a different approach to training in that you shoot one round at each dot (rather than shooting groups) and you really need to focus and use solid fundamentals to make each shot count. It is NOT easy, but is a lot of fun and really can help with hold, trigger control, etc. </div></div>
Link? </div></div>
Here you go. Read through it, you'll get the picture. Good luck.
http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=2470674
Re: WHY DID MY GROUP OPEN UP?
Links added above.
Links added above.
Re: WHY DID MY GROUP OPEN UP?
My guess is that tumbling, while still leaving the insides of the cases black in color, still removes a good bit of burned powder residue out of the inside of the case.
As a result, your tumbled cases have slightly larger case capacity. Larger case capacity means less velocity and you could be getting bumped just off your accuracy node.
My guess is that tumbling, while still leaving the insides of the cases black in color, still removes a good bit of burned powder residue out of the inside of the case.
As a result, your tumbled cases have slightly larger case capacity. Larger case capacity means less velocity and you could be getting bumped just off your accuracy node.
Re: WHY DID MY GROUP OPEN UP?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bowslngr</div><div class="ubbcode-body">My guess is that tumbling, while still leaving the insides of the cases black in color, still removes a good bit of burned powder residue out of the inside of the case.
As a result, your tumbled cases have slightly larger case capacity. Larger case capacity means less velocity and you could be getting bumped just off your accuracy node. </div></div>
I really doubt that, as the volume of crud inside a case tumbled and not tumbled is quite unlikely to make a difference.
Measure them, I might be wrong!
My vote is more for neck friction rather than neck tension. Consistency is key, and my own testing with my own rifle led me to start loading with the case lube left in the necks. It's almost always Hornady One Shot.
Seating pressure on the ram is much more consistent than with dry necks or even tumbled cases. And 5-round groups with my fairly ordinary rifle went from about 1.25 MOA back down to .7-.9 MOA. Not a lot but enough to make the results acceptable for a semiauto.
If your non-tumbled were not cleaned of case lube before charging and seating, that could be it. If they WERE cleaned of case lube, then perhaps the dust residue from tumbling is the culprit.
10 rounds minimum per load trial batch, two, 5-round groups apiece. Run some testing and let us know how it plays out. I can see trying lubed, squeaky-cleaned with a solvent-dipped Q-tip (only two cases per cotton/four per stick, as they tend to pick up and re-distribute crud), and uncleaned--all using only tumbled brass. 30-45 rounds to nail it down would be worth it in my opinion.
For your sake I hope that squeaky-clean is NOT the accuracy winner.
Watch velocity ES too--losing -.2 MOA might be worth it in exchange for 25 fps LESS of ES, if you are shooting beyond 500.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bowslngr</div><div class="ubbcode-body">My guess is that tumbling, while still leaving the insides of the cases black in color, still removes a good bit of burned powder residue out of the inside of the case.
As a result, your tumbled cases have slightly larger case capacity. Larger case capacity means less velocity and you could be getting bumped just off your accuracy node. </div></div>
I really doubt that, as the volume of crud inside a case tumbled and not tumbled is quite unlikely to make a difference.
Measure them, I might be wrong!
My vote is more for neck friction rather than neck tension. Consistency is key, and my own testing with my own rifle led me to start loading with the case lube left in the necks. It's almost always Hornady One Shot.
Seating pressure on the ram is much more consistent than with dry necks or even tumbled cases. And 5-round groups with my fairly ordinary rifle went from about 1.25 MOA back down to .7-.9 MOA. Not a lot but enough to make the results acceptable for a semiauto.
If your non-tumbled were not cleaned of case lube before charging and seating, that could be it. If they WERE cleaned of case lube, then perhaps the dust residue from tumbling is the culprit.
10 rounds minimum per load trial batch, two, 5-round groups apiece. Run some testing and let us know how it plays out. I can see trying lubed, squeaky-cleaned with a solvent-dipped Q-tip (only two cases per cotton/four per stick, as they tend to pick up and re-distribute crud), and uncleaned--all using only tumbled brass. 30-45 rounds to nail it down would be worth it in my opinion.
For your sake I hope that squeaky-clean is NOT the accuracy winner.
Watch velocity ES too--losing -.2 MOA might be worth it in exchange for 25 fps LESS of ES, if you are shooting beyond 500.
Re: WHY DID MY GROUP OPEN UP?
You may be right on the neck friction thing. One way to tell would be to chrono 10 of each. If the tumbled brass results in a noticeably higher ES, that could be the culprit.
You may be right on the neck friction thing. One way to tell would be to chrono 10 of each. If the tumbled brass results in a noticeably higher ES, that could be the culprit.
Re: WHY DID MY GROUP OPEN UP?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: stapletonb08.1740</div><div class="ubbcode-body">
</div></div>
Your rifle was just pissed because you didn't zero it properly
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: stapletonb08.1740</div><div class="ubbcode-body">
Your rifle was just pissed because you didn't zero it properly
Re: WHY DID MY GROUP OPEN UP?
Well i bought some lapua brass and havnt had a problem yet.
Well i bought some lapua brass and havnt had a problem yet.
Re: WHY DID MY GROUP OPEN UP?
If you let brass sit over time the neck tension can vary as it is exposed to the air. If you sized them, then ran them through the tumbler, the media can peen the cases work hardening them. My guess is that if you sized them, ran them through the tumbler, then loaded them without resizing them again the varying neck tension is giving you higher ES on your loads and creating your accuracy problem.
Try resizing them after tumbling then loading them without leaving them sit. This might cure your problem.
If you let brass sit over time the neck tension can vary as it is exposed to the air. If you sized them, then ran them through the tumbler, the media can peen the cases work hardening them. My guess is that if you sized them, ran them through the tumbler, then loaded them without resizing them again the varying neck tension is giving you higher ES on your loads and creating your accuracy problem.
Try resizing them after tumbling then loading them without leaving them sit. This might cure your problem.
Wind......
invest in a $65 wind flag, best money you could spend for group evaluation.
invest in a $65 wind flag, best money you could spend for group evaluation.
Re: Wind......
Did you load the (2) 3 shot groups on a different date? Looking at the "timing" of the groups it looks like the first group was consistantly exiting the muzzle at a different time then the second group. Now im not addressing the size of the group but the "clock angle" Any chance your scale could have been wieghing heavy one day? (yes always is). Just my .02. Cant always judge groups by size.
Did you load the (2) 3 shot groups on a different date? Looking at the "timing" of the groups it looks like the first group was consistantly exiting the muzzle at a different time then the second group. Now im not addressing the size of the group but the "clock angle" Any chance your scale could have been wieghing heavy one day? (yes always is). Just my .02. Cant always judge groups by size.
Re: Wind......
I'd say it has more to do with your barrel heating up than anything else. If you were to do the test again .... but in reverse order, you'd probably get the same results.
I'd say it has more to do with your barrel heating up than anything else. If you were to do the test again .... but in reverse order, you'd probably get the same results.
Re: Wind......
It's wind. It's variable and you can't see it. If anyone tells you that you can PREDICT it, then he or she must think that he or she is God.
It's wind. It's variable and you can't see it. If anyone tells you that you can PREDICT it, then he or she must think that he or she is God.
