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60 Posts
Thanks, I was under the mistaken impression that the 140s weren't stable. Probably need to read this thread. I have a caught a few posts here and there, but lost interest because of having to buy brass. If a 20 inch barrel will stablize 140s at 2750 in a AR15 it would be worth figuring out to make brass out of 308.

SG=1.58 at 2700fps
Plenty stable. I reached 2750 with 37.0 gr Lever but case capacity is maxed using drop tube and funnel. Pressure looks good.
140gr @ 2750? That’s getting pretty close to 7.62x51 territory. Pretty impressive for an AR.
Now I’m going to have to try this. Thanks

60 Posts
I have some velocities to contribute.
I have tried most of the heavier bullet formulas listed. While H4895 performs as well as my best powder it’s case capacity limits it’s use with the 130 and 140 grain bullets. This isn’t a max velocity post, it’s meant as more of a powder comparison.
I have found that WC846 is by far the best performing powder for my rifle. WC846 gave better velocities over the widest bullet weight range. I use it for my Garand and my M1a, just as an afterthought I tried it with the 270msr and it seems to be THE powder for this rifle.
I have tested Lever, H355, CFE223, 2520, H4895 and the WC 846. Averages
117gr Hammer
846- 36gr 3183
H335-35.5gr 3007
H4895 showed pressure signs too early.

124gr Hammer
CFE223- 34gr 2489
H4895- 34gr 2745 very compressed no pressure signs.
2520- 34gr 2588
WC846- 34gr 2770

130gr Speer BTSP #1458
2520- 34.3gr 2598
H4895- incomplete, my sd was too wide, I think my a-d-d kicked in while I was weighing my loads for that one.
CFE223- 34.5gr 2493
Lever- 35gr 2609
WC846- 34.5gr 2742
Hornaday 140 BTSP Interlock
Lever- 34.5gr 2546
WC846-34.5gr 2728
More to come on max loads and accuracy.
141 - 143 of 143 Posts