viewtopic.php?f=141&t=100097
dellet wrote: ↑Sun Jan 29, 2017 12:46 am Spent a little more time with CFE today, learning the quirks of the powder.
I have probably written it off as a short barrel/pistol gas powder. It is just too loud for me and there are to many better choices.
In a carbine gas I think it has some real potential. The added burn time, longer dwell really tames the noise and cuts down on the amount of powder blow back. There is very low port and muzzle pressure. Still a fair amount of gas.
I wanted to see how light of a bullet that could be cycled, I run an 18" 1/10 twist carbine gassed rifle, port size is .110" with a M16 Lmt enhanced BCG and a JP heavy/tungsten captured spring using the heaviest spring. I set this rifle up for hot supers, I've done a lot to slow down the bolt speed as much as possible.
The fun news is that with this setup I was able to have full function shooting Hornady 150 fmj #3037 bullets when suppressed. This might end up being a very good powder for carbine gassed guns.
Now for the bad news.
Still struggling with high spreads.
Right now my feeling is that this is a powder that needs to be compressed. The initial loads in the original post were by the book. 208 Amax, 11 grains at 2.260". ES in the hundreds. Accuracy in the inches at 50 yards.
I seated the 150 fmj's at the cannelure. 11grn 2.040" COL. Although I had lock back on empty, I had possibly the highest ES/SD numbers in recorded history. An ES of 353, SD 133. The group on the right of the pic below is much better than those numbers indicate. It is only fifty yards, I am quite sure at 100 I would measure it in feet.
The group on the left, starts showing some promise.
Back to the Hornady 208 Amax. 11.5 Grains 2.195 COL.
I started this load like I do many. I always record where the bullet will touch the powder. In this case, with 11.5 grains in the case, bullet seated on the powder, COL is 2.220". I put .025" compression on the powder.
Last week's load of 11 grains at 2.255" had an ES just over 200 fps.
This week 11.5 grains at 2.195" had and ES 56, SD 21. There was one odd round that had a very low velocity. when I discounted that as a possible loading error the ES dropped to 24, SD 10. these are numbers that are a reasonable to start with. The change in the group from last week to this reflects that. Again 5 shots at fifty, for reference that is a 1" dot.
I am feeling a little better about the powder and will try to run a couple more loads this weekend. I need to drop some speed, these were cracking at 25 degrees. It is somewhat encouraging tho.