mel Wrote:i think i need t get my hands on some of that powder , 32.7 is prolly as high as id go seeing that speed/dip no increase at 32.9

mel Wrote:i think i need t get my hands on some of that powder , 32.7 is prolly as high as id go seeing that speed/dip no increase at 32.9

Harpoon1 Wrote:Are those normal numbers for Leverevolution?

Yondering Wrote:You can’t accurately judge something like that based on a single shot, especially with such a small difference in powder charge. It’s almost meaningless in regard to pressure or accuracy potential of those loads.

tdbru Wrote:Harpoon1,
remember, the SAAMI pressure spec for the 6.5 Grendel is pretty low. if you see "typical" pressure signs, i.e. flattened primers, you're likely way over SAAMI pressure limit. no issue with the Howa, but not so good if you happen to be driving an AR. Good luck with the load development though. and good that you have enough Leverevolution for a lot of shooting, as reloading components are pretty scarce up this direction right now.
-tdbru

Harpoon1 Wrote:Respectfully, many think you can, and have been successful. That’s exactly how you perform the “Satterlee” method of load development. Single shot per charge, in small increments, to locate stable combustion nodes.

Here is but one example

https://youtu.be/paUMACbJxTs

Harpoon1 Wrote:It’s not the velocity I find all that surprising, it’s the number of single digit ES/SD spreads in the group. I’m gonna try it next in the CZ with a 24” barrel and see what happens. I will be restricted to a much shorter COL, so, should interesting to compare the differences.

jasper2408 Wrote:Well thanks Harpoon1! I wasn't going to test LVR but now you made me go and order 3 pounds to see what all the commotion is about.

I noticed you used a CCI400 primer. Looks like it performed alright for you.

Seems like everybody that has tried LVR has had success with it.

Thanks for the informative post.

Yondering Wrote:Sorry, but “many people” are foolish when it comes to thinking about data variation and sample size. Most results you get from a single sample test will be different if you repeat the same test again. The method above is a particular example of that. Just because people use it and draw conclusions from it does not mean they drew the right conclusions or that it’s a good method.

Single sample results, especially small powder charge increments like you used, place each sample inside the variance range of the samples around it, and to make it worse, with a single sample test you have NO idea what that variance (ES,SD, etc) is. If you shot 5 shots of each instead, you’d see the average velocity be something different than your single samples, and that supposed lack of velocity increase might actually be a normal linear increase and the single samples were just within the ES at each charge.

grayfox Wrote:Example: take uniformly sized and re-sized cases, uniform primers (same lot), a single bullet of some percentage consistency (0.3 gr/100 or so), a single lot of powder, an overall length (+/-0.003 for example) or OAL, all within some manner of tolerances, and powder that is weighed and held to, say, +/- 0.1 gr accuracy (out of say 30 grs) of the powder scale. All of those variables have some small % of variability, so if a load, say, exits the muzzle at a consistent node/MV/angle/etc, then one can say such a load could be accurate in one's rifle. As long as you can continue to produce this load with that process and those tolerances, then its performance will be in accordance with the % deviations of the variables listed above... some of which won't have a discernable amount of MV delta, but some will. In those cases, comparing one set of cartridge load combo "A" against a differing set of combo "B" (ie, increasing powder charges for example), one can use es/sd of those load sets as an indicator of potential accuracy. [Certainly more load sets of equal combo are better than a single one.]