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Joined: Aug 2021
Since I don't see anyone posting about IMR 4895, even though the 6mm ARC Facebook page with QL data shows promise, I might as well post some findings. I went out to the range to test a few loads with IMR 4895 for velocity, pressure, and function. Velocities are two-shot strings.
Gun: AR-15
Barrel: 18" Proof Research SS
Bolt: JP HP bolt
Muzzle Device: GA Recce 7
Magazine: ASC 6mm ARC 15-rd
Bullet: 108gr Berger Elite Hunter
Lengths: 2.265" (1.650" 3-24 comparator)
Case: *-* 6.5 Grendel once-fired
Lengths: 1.480" (1.185" B350 comparator)
Primer: CCI 450
Velocity ES
25.5gr 2337 fps 5 fps
26.0gr 2398 fps 13 fps
26.5gr 2444 fps 8 fps
Since temp. stability of IMR 4895 is in question overall, I will play with that down the road.
The moment you've got it figured, you're wrong.
Posts: 222
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04-18-2022, 02:55 PM
(This post was last modified: 04-19-2022, 07:48 PM by alwie.
Edit Reason: removed redundant questions
)
(04-18-2022, 05:48 AM)notagrendel Wrote: Since I don't see anyone posting about IMR 4895, even though the 6mm ARC Facebook page with QL data shows promise, I might as well post some findings. I went out to the range to test a few loads with IMR 4895 for velocity, pressure, and function. Velocities are two-shot strings.
Gun: AR-15
Barrel: 18" Proof Research SS
Bolt: JP HP bolt
Muzzle Device: GA Recce 7
Magazine: ASC 6mm ARC 15-rd
Bullet: 108gr Berger Elite Hunter
Lengths: 2.265" (1.650" 3-24 comparator)
Case: *-* 6.5 Grendel once-fired
Lengths: 1.480" (1.185" B350 comparator)
Primer: CCI 450
Velocity ES
25.5gr 2337 fps 5 fps
26.0gr 2398 fps 13 fps
26.5gr 2444 fps 8 fps
Since temp. stability of IMR 4895 is in question overall, I will play with that down the road.
How many rounds down your barrel?
Twist rate 1:7.5?
Posts: 181
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....thanks for posting your results, it's good info for folks that live in locales that have fairly consistent year-round temps.
...I appreciate folks posting their results with various powder/bullet combos, especially as powder variety available isn't what it used to be. I also like to see posts using powders that can be cross-utilized for one of my other calibers, which in this case 4895 is one of the touted powders for 223/556.
Posts: 174
Threads: 17
Joined: Jun 2020
Gorden's reloading tool (GRT) was very accurate in it's predictions of 6 ARC and IMR 4895 and was with in 25 fps or so when I tested it with Hornady 105's. I think 26.5 is pushing the 55K psi limit for a gas gun. From my experience it is also in the powder compression arena.
Thanks for sharing your data. How were the groups?
