Okay, sorry for the delay.
The first range day of the season never goes smoothly. Every year, I vow to make a checklist for all the crap I have to haul along, which is spread out all over the house, but I haven't made it yet. Don't want to face the fact that my memory isn't as good as it used to be. When I'm trying to get out of the house at a specific time, it's like trying to run in knee deep mud. Can't go fast enough to suit me and the wife is inhaling a long wind to start in on all the honey-do's I have to get done "Sooner than Later!" Needless to say, I forgot a few things, but I got out on time.
This being a new caliber and the apparent choices of powder being so vast, I wanted to calibrate QuickLoad with as many real world results as possible on this first outing. Not wanting to entreat too many variables, I kept everything except the powder, the same. For my initial powder choices, I did some advance measuring to see how much I could fit in a case for a given bullet and COL, to see whether they would deliver performance as predicted by QuickLoad.
Here's a table of how much powder I could fit into the case. Where there are two measurement divided with a / the second charge was all that QL would recommend without exceeding the spec chamber pressure. Boy that was a bum steer, but more on that later.
Since my intended bullet for this outing was the Hornady 125gr SST, the charges in purple were near what I loaded to. Other than with AR-Comp, which QL predicted never reaches maximum pressure, but which historically has delivered exceptional consistency and accuracy in other calibers, I dropped a grain or two to be in the middle of the QL predicted safe pressure range. I knew I could always work up from there. Talk about foreshadowing...
Here's a table of the achieved velocities for the given charges.
As you can see, I didn't come close to achieving any of those predicted velocities, so there is plenty of opportunity to bump and run, but to be honest, I would've been a lot happier to have been in the vicinity as there isn't tons of capacity left to gain the increases I'd like to see. Many of those first loads struggled to even achieve the same velocity as the 150gr PSP factory loads. Oh well, that leaves me a challenge for the next outing, though I also have some catching up to do with 450b tests I ran out of time to complete last year before the thermometer plummeted to the "no wimps welcome" level.
So what about accuracy. It appears that the 125gr SST needs more velocity to stabilize, or my barrel likes a different bullet setback so the jury is still out on that. More importantly, I need to remember my benchrest and rear bag, not to mention learn how to shoot a lightweight AR again, having not shot since last fall. ARs have never been inherently easy for me to put away and pull out 6 months later with the same degree of mastery. Not at all like a bolt action in that regard.
Here's how they flew:
You may no doubt have noticed the mention of an FCD. Not to be confused with the implementation of an FCD for the 450b. This is the actual implementation that Lee intends them to be used. Several years ago, I owned a 300 OSSM upper. I modified a 300 WSM FCD to fit it replacing the taper crimp at the case mouth. I modified it again to fit the 30 RAR since I sold the 300 OSSM a while back and the buyer didn't want it. Surprisingly, it didn't do anything for velocity or accuracy, but the sample was small.
WRT accuracy. I believe a lot of the lack of tightness in the groups was due as much to my personal rustiness and having to shoot off of chunks of 6x6 timbers covered with old carpet and a rear sandbag, as opposed to a nice BR front rest and matching rear bag which I forgot. Also, I did not clean the bore the entire time, which is a little long for doing load testing IMHO. So, there's room for improvement on all fronts and a commitment to chasing them. First and foremost, I have to tune QL to compensate for my real world results.
More to follow.