IMR 8208 In the 6.5 Grendel

Shanerd

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Does anybody have any experience using IMR 8208 in their 6.5 Grendel. Performance? Loads?
 

Ishallbie O'Cullkillin

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Re: IMR 8208 In the 6.5 Grendel

I tried it about 6 months ago with a 19.5" barrel & 123gr Scenar. It was one of the very FEW powders that got to 2550fps and kept the pressures down, also could load to max without deforming the bullet due to compressing powder. I didn't use it because I had a lot of AA2520.
 

DHDeal

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Re: IMR 8208 In the 6.5 Grendel

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Shanerd</div><div class="ubbcode-body">Does anybody have any experience using IMR 8208 in their 6.5 Grendel. Performance? Loads? </div></div>

Some.

AA Overwatch, 24" Lowther Walther barrel, JP trigger, Leup MK4 4.5x14, off of a solid bench with a high quality heavy rest:

29.5 8208, 107 SMK, 205M, AA brass. No velocity data, but no obvious pressure signs in 95 degree heat.
29.5 8208, 107 SMK, RP 7 1/2, AA brass. No velocity data, but no obvious pressure signs in 95 degree heat.
29.5 8208, 108 Scenar, 205M, AA brass. No velocity data, but no obvious pressure signs in 95 degree heat.

All shot about the same into .6" or slightly under. The max is 29.8 I believe, but saw some slight pressure signs so I backed it to 29.5. I do use more AA2520 and don't mind a little crunch
wink.gif
.
 

DHDeal

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Re: IMR 8208 In the 6.5 Grendel

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: DHD</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Shanerd</div><div class="ubbcode-body">Does anybody have any experience using IMR 8208 in their 6.5 Grendel. Performance? Loads? </div></div>

Some.

AA Overwatch, 24" Lowther Walther barrel, JP trigger, Leup MK4 4.5x14, off of a solid bench with a high quality heavy rest:

29.5 8208, 107 SMK, 205M, AA brass. No velocity data, but no obvious pressure signs in 95 degree heat.
29.5 8208, 107 SMK, RP 7 1/2, AA brass. No velocity data, but no obvious pressure signs in 95 degree heat.
29.5 8208, 108 Scenar, 205M, AA brass. No velocity data, but no obvious pressure signs in 95 degree heat.

All shot about the same into .6" or slightly under. The max is 29.8 I believe, but saw some slight pressure signs so I backed it to 29.5. I do use more AA2520 and don't mind a little crunch
wink.gif
. </div></div>

With an Oehler chronograph to tell the story, here is the data I got from the 8208. The rifle now wears a Satern 24" 5R barrel, .875 GB, .820"ish muzzle with crown only.

107 SMK, 450, 29.5 8208, 1.683" using Possum Hollow comparator - 2752fps average, 15 es, 6 sd. .420 moa 5 shot group. This load I have taken to 600 yards with damn near the same moa.
108 Scenar, 450, 29.5 8208, 1.736" using Possum Hollow comparator - 2726fps average, 17 es, 7 sd. .660" 5 shot group.

FWIW, I have been using Leverevolution with the 123's and it is really good powder with no demons. I get the velocities I got with 2520 (2640fps with sd's around 10) with none of the pressure signs. The brass does not show any flattened primers or exjector swipe that I saw with 2520 and factory AA and some older Black Hills 6.5 Grendel ammo. The Lever powder, a 120 Berger, 450 primer, jumped .005" will shoot under .5 moa elevation time and again @ 600. I don't doubt that alot of the accuracy I see @ 600 is from a great barrel (Satern), great trigger (JP), great rest (Randolph), great components, and a good day for me, but the Lever and 123's really shoot good. The Berger 120's however, shoot, well great!
 

TRAAV

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Re: IMR 8208 In the 6.5 Grendel

I have an 18" Barrel and run 28.2 grains and have went higher but accuracy wasn't there. they are running about 2425
 

CTone03

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Re: IMR 8208 In the 6.5 Grendel

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: DREMEL</div><div class="ubbcode-body">I have an 18" Barrel and run 28.2 grains and have went higher but accuracy wasn't there. they are running about 2425 </div></div>

Same here (18" barrel). I did an OCW test with 123 grain Scenars and found a node from 27.9 to 28.5 grains. My average velocity for 28.3 grains is 2,422 fps if I recall, and around 2,465 fps for 28.5 grains; the 28.3 is my load though, as the 28.5 load will sometimes throw a shot here or there, being right at the top of the node for my gun. I went all the way up to 29 grains in fireformed AA brass with no pressure signs whatsoever, and the cases mic'd out like they should. I'm only seeing the start of some accuracy there, and I don't want to run it any hotter. For me the Scenars and Amaxs group exactly the same.
 

fireguyty

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Re: IMR 8208 In the 6.5 Grendel

Drifter,
Load, velocity and temp sensitivity for AR Comp please.

Thanks
 

Drifter™

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Re: IMR 8208 In the 6.5 Grendel

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: fireguyty</div><div class="ubbcode-body">Drifter,
Load, velocity and temp sensitivity for AR Comp please.

Thanks </div></div>

123 gr Scenar or A-max
28.0 gr AR-Comp
Hornady fired brass
.287 neck bushing
2.250 COAL
light crimp using Lee FCD

~2475 fps (+ or - 25 fps) from 18" barrels.

Use at your own risk. Appears safe in my rifles. Start lower and work up.

Temp stability of AR-Comp has been documented elsewhere on this forum by others. Try the SH-Google search.
 

Irokcrawl

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Old post I know but after testing today out of my 24" Precision Firearms Grendel 29.1Gn of 8208XBR with a 120Gn Amax seated to 2.2450 showed right at 2596-2600fps or so with a 6fps SD and shot roughly a 1/3" four shot group at 100; Ill measure the groups later once I have a break from work. I have not tested this past 100 but will do so next week and see if the results are the same. 28.5 also did well and was close to 1/2moa at roughly 2560fps. BL-C(2) from everything I have tried was horrible with nothing below a 1" group with the 130gn vlds at multiple seating depths and the 120 and 123gn AMAX. This has been the most difficult gun for me to load for so far but its for my daughter so 1/2moa is fine for now. Im not stressing over anything more from a gas gun.

EDIT: 29.1 was the load that pulled up to 2600fps and a 0.1430 group at 100. 28.9 did pretty well also with a 0.349moa group.
 
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arnie19

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I had real good long range accuracy with 100 gr. A max and 30.5 of 8208 in my 6.5 sporter (Grendel clone )