08-30-2012, 10:09 PM
Well, I made it out the range this morning. I started with TxGunner's loads. Every round successfully ejected the empty. But it never successfully loaded the next round or locked back on an empty magazine.
First, my hardware:
16" AA barrel, mid-length gas system
1:8" twist rate
"Standard" carbine buffer, tube and spring
I do have another lower with a rifle tube, buffer and spring. I have fired the Grendel upper on both lowers, and they function interchangeably with full power loads. I did not think to try the rifle lower today. Maybe next time.
All loads were 8208 powder under the 160 grain Hornady RN (0.264).
I had some Wolf (PPU) brass with large rifle mag primers.
I also shot some out of Hornady brass using small rifle magnums. Surprisingly, the hornady brass was giving 200-300 fps faster for the same charge.
Brass / Charge / Avg Vel / StdDev / ES
Wolf / 13.9 / 1110 / 56 / 109
Wolf / 13.7 / 1086 / 19 / 27 - 2-shot group
Wolf / 13.5 / 1182 / 66 / 131
Horn / 13.9 / 1417 / 109 / 154 - 2-shot
Horn / 13.7 / 1371 / 67 / 95 - 2-shot
Horn / 13.5 / 1265 / 142 / 201 - 2-shot
Point of impact is about 3" below my full power loads at 50 yards.
My 1:8 barrel is not stabilizing the 160s. All of the sub 1200 fps rounds were keyholing.
An interesting side note: the 160 grain round nose want to fall into the hornady cases once they get a little past the cannelure. Someone on here commented they noticed that, but I can't remember who. In order to get them to hold, I put the hornady's back through the sizer just enough to increase the neck tension. I had no problems with the Wolf brass holding the bullets.
First, my hardware:
16" AA barrel, mid-length gas system
1:8" twist rate
"Standard" carbine buffer, tube and spring
I do have another lower with a rifle tube, buffer and spring. I have fired the Grendel upper on both lowers, and they function interchangeably with full power loads. I did not think to try the rifle lower today. Maybe next time.
All loads were 8208 powder under the 160 grain Hornady RN (0.264).
I had some Wolf (PPU) brass with large rifle mag primers.
I also shot some out of Hornady brass using small rifle magnums. Surprisingly, the hornady brass was giving 200-300 fps faster for the same charge.
Brass / Charge / Avg Vel / StdDev / ES
Wolf / 13.9 / 1110 / 56 / 109
Wolf / 13.7 / 1086 / 19 / 27 - 2-shot group
Wolf / 13.5 / 1182 / 66 / 131
Horn / 13.9 / 1417 / 109 / 154 - 2-shot
Horn / 13.7 / 1371 / 67 / 95 - 2-shot
Horn / 13.5 / 1265 / 142 / 201 - 2-shot
Point of impact is about 3" below my full power loads at 50 yards.
My 1:8 barrel is not stabilizing the 160s. All of the sub 1200 fps rounds were keyholing.
An interesting side note: the 160 grain round nose want to fall into the hornady cases once they get a little past the cannelure. Someone on here commented they noticed that, but I can't remember who. In order to get them to hold, I put the hornady's back through the sizer just enough to increase the neck tension. I had no problems with the Wolf brass holding the bullets.