Powder thrower variance

[Gwion]

Also, try weighing your projectiles, even "match" quality can vary by a grain or two. Just throwin' in another "curve" ball for y'all.

Yep, i do that too, as well as weight sort my brass. Like i said, i need all the help i can get!

Actually, as someone else pointed out, i like to know my rifle & ammo are shooting as consistently as possible so i have nothing to blame but my need to improve my skills if (when) i am not performing to scratch. It's not a popular attitude with all but i like my hunting/pest control rounds to shoot well inside 1MOA when testing; if it is bigger/worse than 0.8MOA over 3 Groups of 5 i keep tweaking it. For my target rounds i aim for 0.4moa or better.

I get that all those other things play more of a role in a shooter's performance but it's good to at least remove the variable of rifle and ammo from the equation. It gives you confidence in your gear and confidence in your gear makes for a better performance and trouble shooting of your technique.

I do agree that when loading on the right node, a small variation in powder charge makes little difference but in the past i have chosen a rather toasty load that shot 0.5moa but 0.3gn more made it open up to 1.5" (and flatten primers). I soon gave up that load and sacrificed FPS for a more stable load that will only be affected slightly by small variations. I now look for a load that shoots very similarly within 0.6gn (0.3gn+/-) and load bang in the middle as much as possible.

If you are confident that your thrower is +/- 0.1 or 0.2 gn, then why not use it to speed up the process but i have found that either my thrower or my operating technique is not that consistent so i still weigh all my loads, ie: throw light and trickle up to charge. Yes, i have been known to add or remove a few granules of powder when loading for target work... (kind'a embarrassing when i go to such lengths but still only manage a 50-52 on an average 500-600yd F-class shoot! As i said, still working on all my techniques and wind reading so want to remove my gear as a variable as much as possible. Next step is getting a stock specifically set up for prone shooting, not my FrankenStock that has been "modified" from a Boyds thumb hole hunting stock (not designed to ride a bag very well or consistently).

[Gwion]

Here is a quote from a "cliff notes" of the Houston Warehouse Project:

" - Powder charges, as long as they were fairly consistent and bracketed within a couple of grains, were not important. He threw all of his charges with a Belding & Mull powder measure, and for one experiment he shot groups using three different powder measure settings (51, 52 & 53) … all three groups were identical.
- Lot variation in powder didn’t seem to have any effect on accuracy, even on when using IMR 4198, which has a reputation for varying considerably from lot to lot. He would just buy powder as he needed instead of laying in a big supply, because he found no evidence to support that powder lot variance affected accuracy in the least."

http://precisionrifleblog.com/2013/10/1 ... -accuracy/

From this, my statement of "one or two grains either side" is incorrect and should have been "a variance of +/- 1grain".
This is a sticky point that i do have trouble getting my head around but that was the findings of the experiments.

[bladeracer]

I spent $300 on the Gempro250, on top of what I spent on several other devices in search for the ultimate accuracy.
What it taught me is that that level of accuracy is not required.
If we only had the technology to weigh our charges to a quarter of a grain we would be no worse off.

[Gwion]

A Lamborghini is not really required either but it's nice to have if you can get it.


Some people just enjoy chasing the best accuracy they can attain.

[Gamerancher]

What is underlined says 2 grains. Thats what I am referring to

And, what I am referring to is the original post.

My comments are in relation to his inquiry about whether the 0.2gr variance he has found with his powder thrower is going to have a large bearing on accuracy.
For the average shooter, that amount of variation 'aint going to be noticable taking into account all of the other factors that affect "perceived" accuracy that I mentioned.