Well guys I no longer shoot a matrix, but I am sure I will shoot one again in the future as soon as I can buy another one. However I noticed a VERY important detail about tuning the LPR and getting your gun to shoot at its absolute BEST performance.
As some of you know I did a ton of testing with the DM8 using different greases, and LPR settings all over a chronograph. I would like you guys to know some of the most important things I discovered about this gun and getting it to its top performance.
***Important detail #1... Keep the LPR seat o-ring (the little 010 o-ring on the brass adjusting screw at the back of the LPR) in TOP condition. Believe it or not, even the SLIGHTEST bit of shredding on this o-ring can cause you to have to elevate your LPR a whole lot, and prevent you from getting consistent readings over a chronograph at those lower LPR pressures you would like to run. THE MOST important thing to watch out for is that when you replace this o-ring, that your EXTREMELY careful when screwing the LPR adjustment screw back into the gun. The truth is, if you screw the LPR seat ALL THE WAY into the LPR, your going to shred this o-ring when you start backing it out to set your LPR... I would say about 85% of the time. Not enough to cause a LEAK per say... but enough to effect your performance drastically, without you even noticing it. The reason I say this is because during my testing, I was resetting the LPR from scratch EVERY time I was changing my grease out, for testing purposes. I noticed that for some reason, I was having to use higher and higher LPR pressure, and for a while I blamed it on the greases being better than one another. Now I must stress, after discovering this, I actually tried an experiment... it went as follows...I went out and bought a whole bunch of 010 o-rings for the LPR seat. I kept noticing that even after 1 or 2 grease tests, that involved me putting the LPR all the way in, then backing it out 3.5-5 turns, and testing the gun over the chronograph, I would find the LPR set o-ring shredded a bit, the next time I pulled it out. So with my new o-rings I first tried installing a brand new one and greasing the hell out of it. I turned the LPR seat all the way in until I felt it come to a snugging stop. When I would start backing it out it felt tight, then all of a sudden it would loosen. I finally came to realize that this was the feeling of the o-ring actually shredding, then the shredded piece coming off. I did this 3 times and shredded 3 different o-rings. The second and third time I tried not quite turning it in so tight, or turning it in slowly. Nothing, shredded. I realized soon, that having this o-ring in great condition was going to be a must, to achieve low LPR pressures, and amazing consistency.
SOLUTION: I had to come up with a way to adjust my LPR, KNOW how many turns out it was at (for the sake of knowing your gun is in the right Operating Pressure range), but without having to turn the LPR screw all the way in, where it inevitably seemed to suffer some shredding damage. So, its simple. I turned my LPR to 3 turns out, and counted how many turns out it was before the threads were out. I believe it was roughly 10 turns. So I changed this o-ring, greased it, and turned the seat in until I hit this point again. Just for good measure I gave it two or so more turns in and noticed it started to get tighter, but then I backed it out to where it was, knowing that a 1/2 turn or so inward would have set me back to 0, just judging by the feel. Sure enough, now I had an o-ring on my LPR seat that was in perfect condition, and set. Guess what happened...
My DM8 (known for needing 4-5 turns out) was suddenly able to run about 2.5-3 turns out, in the cold. The gun was ridiculously quiet, to the point where it felt like you HAD to be shooting low, more consistent than I've EVER seen it over the chronograph, and had no kick, I mean NO kick, as in it was completely undetectable, and NO shootdown or FSDO. Go figure... (for the record, my dwell is at 20 at the moment, due to the cold weather)
***So important detail #2... ALWAYS realize that you may have the LPR set too low to take advantage of the FPS being put out by the HPR! If your LPR is even a little bit too low and you don't know your gun all that well, Raise your LPR a little higher than it should be to see whether you gain a significant amount of FPS over the chronograph. If your LPR is even a LITTLE too low, your gun will appear to be performing erratic. Depending on what you happen to think the problem is, you may even attempt turning up your HPR. What ends up happening is you can eventually turn your HPR up enough to create symptoms that will confuse you, like leaks and such. This happened to me with my dm8, and man did it get ridiculous.
Either way the most important detail of the 2 is the first one. So,if you are someone who feels your DM is not as smooth as it should be, or not as consistent as it should be, take it apart, clean and lube the HPR, LPR, and bolt, replace your LPR seat o-ring, and tune it by turning it inward until the gun stops firing, then back it out from that point only! Don't make a habit of touching the LPR unless it needs to be touched, and DEFINITELY try not to every turn it in all the way. Believe it or not, when the screw gets snug, your probably likely to shred the o-ring EVERY single time, and not even realize it's harming the performance. Or do what I did, and count the turns from 3 turns out, to the point where the seat is out of the gun.
I'm sorry if this post seems stupid, but after all of my testing, I feel that its best for me to share with all of you the key points that truly turned my gun, from an average to mediocre DM8 at best, to an amazing shooting one. For the record, I use Lurker Lube and Monkey Poo. Either one performs great. And believe me, I've tested EVERYTHING.
Thanks guys, and I hope this post serves to help someone.