Since we are discussing this on a forum I'm going to start with this first- I'm not arguing with you. You make some very good points and one has to be careful about what info they put on a forum. I don't disagree with anything you wrote. Some of it was new, some of it is reloading 101, but it has to be said. You've obviously been chasing a good load longer than I have. I hope we can continue the conversation.
"The reason primers are blown and cases torn up, you're over pressure,.. Stop." I know...
I worked up to it in .1g increments on purpose. It literally went from hot but not terrible to f-that in 0.1g. I was pretty sure that it was going to be hot because it was hot the last two times I loaded it. Just not that hot. Most of the cases are trashed because the &%@($ bolt smashed the case mouth. Yes I know... that means the gas system needed to be tuned. I've had a love hate relationship with the AR platform for about 8 or 9 years now. Mostly hate. Ironically that's why I have "a few". They test me...
I'll take a good bolt gun over an AR any day. I had this AR's gas system tuned but I think that when I cleaned the barrel up that changed. The barrel was nasty. I wish I had borescoped it before I spent hours cleaning it. Yesterday, the rifle was very undergassed down at the lower charges and slightly undergassed at the top end. I have a Superlative Arms adjustable gas block. I like it. It does a nice job when it's set right. I just need to clean the rifle and set it. But first I need to find a charge that I like or at least hate less.
The last load had some raised ejector marks on it that lead me to toss the brass. It's Gorilla brass and has been fired at least 4 times. Primers were not cratered or flattened. The load before the load that I tossed the brass might have an ejector swipe mark on it but it's very faint.
"With copper bullets ya need .050" jump according to most manufacturers."
This is one place I'm delinquent. I went for maximum mag length on the last test. The few times I've tried to find jam (and then back it up 0.XXX") I ended up with round that wouldn't load in the magazine (not the 8.6BLK). I assumed that would be the case with the 8.6BLK. In short, I don't know how far from the lands the bullet is. I do know that I picked up some velocity by moving it
out .025", 2.800" to 2.825". I have a little bit of room to go a little longer. I think I'll see where the lands are and see where .050 come out. I have a feeling it'll be too long for the mag but we'll see.
"RL 17 33.7 gr max should get around 1700 fps at max pressure...all are a compressed load"
I don't have any RL17. I wish I did. I'm on the list at Powder Valley but I'm not the only one. RL17 is gone right after the email that it's in stock arrives. I have IMR4350 (next to RL17 on the burn rate chart) and RL19 (quite a bit slower). I can get about 30-31g of IMR4350 in a case but, as you say, it's a compressed load. I haven't been willing to play in the realm of compressed loads with this round. I might have some H335. If I do what I always do, and look sideways at max, and slowly work up to what my rifles max is, maybe I'll find something I like. Or I can move to a lighter bullet. Idk...
"WITH ONLY...2.825" COAL , 280 gr copper LRX bullet 1.864" length." I'm assuming 1.864" is calculated base to ogive? I haven't found a Barnes bullet yet that has good base to ogive consistency. I load to fit the magazine. I have to. "Only 2.825" is the limitation of the magazine. I might be able to go to 2.835. I need to back up and find the distance to the lands.
"weigh all charges .2 increase will get you into trouble." The fact is, I double weigh. I let the RCBS Chargemaster do the initial drop, then dump that into a TRX-925 and adjust that to the nearest 0.
01g. Then dump it in the case. For the record, .1 grain was the difference between warm and too hot. BTW- the scale I use reads at .01 grain, but it's accuracy is to the first decimal place. It took a lot of loads to condition myself to allow 0.01 grains and not correct it. I still don't allow -.01g
All of the following info is in the PDF that I attached in the other post. The best group was load 2 and it also had the best SD. For the record I don't put much, if any, stock in SD values for 3 rounds. It's a statistically insignificant number of samples.
Average velocity for test two was 1,502.2 fps and the group was 1.094 MOA. Group one had the best MOA (0.980) but the difference could have been on the shooter (me).
Strictly from a short range hunting perspective- Calculated velocity and energy looks like this- 1,500fps mv gives us:
1,329 fps at 200 yards with 1,099 fpe.
1,412 fps at 100 yards with 1,240 fpe.
1,456 fps at 50 yards with 1,319 fpe.
I don't know if the LRX will expand at the velocity / energy that is listed above. That's the $2.00 question.
One thing I see in the targets is the effect of barrel harmonics. That little skinny-assed barrel must be whipping pretty good.
