Page 1 of 5 123 ... LastLast
Results 1 to 15 of 66

Thread: Getting back to weighing powder

  1. #1
    Join Date
    Feb 2003
    Location
    Tennessee
    Posts
    5,171

    Getting back to weighing powder

    As I recall, I made the statement that nobody could tell the difference in the accuracy of a rifle from weighed charges vs charges that varied .2 grains. I offered to jump a plane and go see, if anyone claimed they could pick out the shots that had the .2 variance. Larry Costa took me up on it but I think he understood the deal to be load weight rather than the age old question of whether to drop or weigh. He added a bunch of criteria that wouldn't affect the test so long as the shots were "blind".

    OK, the season is dwindling such that Larry might not become distracted and I'm still in. The question to Larry is:

    Do you still believe you can pick out the shot that varies 2 tenths grain from the others? Alternatively, pick out the group within an 5 target agg that has variance - all others being weighed?

    It would be simpler to pick out the shots but I'm willing to go either way. Restating, the purpose of the test is to determine if the variances in powder weight as a result of using a powder drop are discernible on the target.

    Larry - are you still in on this? I can fly close on the cheap from Chattanooga.....

  2. #2
    Join Date
    Jul 2003
    Location
    Misplaced . . .
    Posts
    3,607
    Mr, Stool. No, you don't get it.

    Here's the thread, all 95 posts...See, for example, post 85 -- but you'll have to read more to get the full picture.

    http://benchrest.com/showthread.php?...nth-of-a-grain

    Edit: Here's the challenge:

    I'll save up some money and go anywhere Southwest flies. We'll fix up some 6PPC cases so they all look alike and then load up some weighed charges and some deliberately 2 tenths spread. I'll pass 'em out so you won't know which it is. After shooting 15 groups with the .2 spread and 5 groups with the exact weight - you pick which ones that had the exact weight. If, for some reason, you can't pick the weighed groups we'll do it again with 3 tenths variance.
    Last edited by Charles E; 11-06-2013 at 10:40 PM.

  3. #3
    Join Date
    Feb 2003
    Location
    Tennessee
    Posts
    6,441
    Wilbur, IMO the charge weight can be off probably more than your 0.2 grains IF the load window of that setup allows. I have had barrel/bullet situations where probably as much as +/- 1 grain would allow all bullets to "go through the same hole". (I use the Brady Knight definition to define "same hole")

  4. #4
    Join Date
    Feb 2003
    Location
    Tennessee
    Posts
    6,441
    Note to Charles E, who is going to feed Wilbur while these exhaustive tests are going on??

  5. #5
    Join Date
    Feb 2003
    Location
    Tennessee
    Posts
    5,171
    Quote Originally Posted by stool View Post
    what are you going to use for powder and what thrower will give you that .2 tolerance >>.

    seems i remember some guys weighing and throwing saying n133 is thrown at .3......
    am i missing your challenge ??
    I'm fairly sure that folks can throw 133 closer than three tenths. It's all in the technique. Boyd Allen can elaborate as he has it to a science.

  6. #6
    Join Date
    Feb 2003
    Location
    Tennessee
    Posts
    5,171
    McDoubles are on the dollar menu in Bradenton - I called ahead.

  7. #7
    Join Date
    Dec 2003
    Location
    washington.........STATE that is.
    Posts
    10,272
    Yeahhh but they just went up to a dollar nineteen this week, and it's now the "dollar menu and more" LOL!

  8. #8
    Join Date
    Feb 2003
    Location
    Tennessee
    Posts
    5,171
    Where's Larry?

  9. #9
    Join Date
    Feb 2003
    Location
    Tennessee
    Posts
    5,171

    Until Larry drops by.....

    Anybody else?

  10. #10
    Join Date
    Feb 2012
    Location
    SW.Pa.
    Posts
    894
    Wilber, I shoot 1000 yd. bench rest and i don't think you would want to bet the farm on a .2 powder charge variance. .1 isn't hard to see but at short range it is only .1 as far….. jim

  11. #11
    Join Date
    Feb 2003
    Location
    Tennessee
    Posts
    5,171
    Quote Originally Posted by jim1K View Post
    Wilber, I shoot 1000 yd. bench rest and i don't think you would want to bet the farm on a .2 powder charge variance. .1 isn't hard to see but at short range it is only .1 as far….. jim
    I'm fairly sure you're right about the longer ranges. Anybody ever done a blind test to see if a variance can be confirmed as detrimental?

  12. #12
    Join Date
    Feb 2012
    Location
    SW.Pa.
    Posts
    894
    Wilber, I was blind when i first started…….. I used a Harrell's powder measure and a digital scale shot big 7-9" groups. went to a tuned balance beam scale to check the Harrell measure and the groups got smaller. Last was a Sartorius GD 503 and the groups are down to the 2" range, i hold a .01 with it. I still use the Harrell's measure…….jim

  13. #13
    Join Date
    Dec 2004
    Location
    Oswego, New York
    Posts
    1,097
    Wilbur If you have a rifle that will shoot them dam near in the same hole at 100-200 is there going to be more than one person handing you the random amo and one guy doing the shooting. Will all groups be measured, cause my eyes aren't that good anymore. But I'm with Jim1k on the 1000 yard stuff there is a difference.

    Joe Salt

  14. #14
    Join Date
    Feb 2012
    Location
    SW.Pa.
    Posts
    894
    Wilber, I did shoot short range at one time. and i have three 1000 yd. light guns that will shoot in the zero's at 100yds. The Dasher is super accurate have barrels that shoot in the mid zeros. and i do all my testing under wind flags. I now trim and point Spencer and BIB bullets and i anneal every time. I think i have the Dasher figured out up close and long. I now hold seating depth to .0005, so try to believe you can see .1 variation @ 1000. I try to leave nothing to chance, i am the weak link in this equation ………. jim

  15. #15
    Join Date
    Feb 2003
    Location
    Tennessee
    Posts
    5,171
    Quote Originally Posted by Joe Salt View Post
    Wilbur If you have a rifle that will shoot them dam near in the same hole at 100-200 is there going to be more than one person handing you the random amo and one guy doing the shooting. Will all groups be measured, cause my eyes aren't that good anymore. But I'm with Jim1k on the 1000 yard stuff there is a difference.

    Joe Salt
    Had to re-read this to realize there was a question. Doesn't really matter how it goes down as long as I know which ammo it is and the guy doing the shooting/guessing doesn't. A third party would only be needed if I can't be trusted to tell the truth. The shooter/guesser has to decide which ammo is different.
    Last edited by Wilbur; 11-12-2013 at 08:05 PM.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •