Temp stable, heavy bullet powder.

[gofastman]

I was hoping someone could suggest a good powder to get some 129gr SST or ABLR pills moving at a respectable velocity out of my 18" barrel.
I bought a can of CFE 223, because it's what they had at Cabela's when I went there, but I gather it's not the best choice for cold weather.

Alliant Power Pro Varmint caught my eye. It's burn rate is similar to Reloader 12 according to the Googles. That would put it in line with other powders that seem popular for this caliber.
The other one is perhaps AR Comp, which advertises good temp stability.

Any others I should look at?

[-Justin-]

I'd try some RL-17 if you don't mind compressed loads. Depending on how long you can load out to and your case capacity it's possible to get 2450-2500 fps from an 18" barrel.

[Bfglowkee]

RL17 is not ideal for the Grendel or temp stability. If that burn rate was to be used though I would say RL16 but the speeds will not happen due to bulk of powder. But yes the compressing of loads is not to be feared with those slower burning, bulky powders.

[Bfglowkee]

Not saying don?t try RL17 btw....just mentioning the performance of the Grendel is geared more toward faster burning powders. This is why Varget fails to reach potential in the Grendel...too bulky and slow for the design. Great accuracy though.

[Klem]

H4895 is single-based so more temp stable than double-based powders. I use it for heavier projies.

Varget is another single-based powder but is arguably too slow for typical Grendel length barrels.

RL17, AR-Comp and CFE are all double based so more susceptible to temp changes. AR-Comp is RL15 reformulated but ended up slower than 15, more like Varget's speed.

I find this chart helpful http://www.adi-powders.com.au/powder-equivalents/

[gofastman]

Do primers seem to play a significant roll in performance with double base powder velocity spread with this cartridge?
I use Remington 7 1/2 primers, but I really only am familiar with them in my .454 Casull, which is pretty easy to get a decent burn in with heavy bullets and good neck tension (and faster burning powder than the Grendel, naturally).

[1Shot]

Anything you change in a load can improve on or be detrimental to it's performance. The only way to know is to try for yourself in YOUR rifle. On YouTube "Jonny's reloading bench" he has a BUNCH of load work up for numerous powders an bullets for the 6.5 Grendel and other calibers. I have been watching the process he is doing to clone the Black Hills 5.56 77gr "Sierra" load. This has been a long process with the usage of a BUNCH of powders which most are usable in the Grendel. In his testing IMR 8208 and ARcomp have been very temp stable powders. On the average most "stick powders" are much more temp stable than "ball" powders.

[jbmarshtx]

H4895 is single-based so more temp stable than double-based powders. I use it for heavier projies.

[/URL]

I just ordered a pound of this for reduced loads for silhouette in my creedmoor. Do you have any velocities for the 'heavier' grendel bullets with 4895?

[Klem]

I just ordered a pound of this for reduced loads for silhouette in my creedmoor. Do you have any velocities for the 'heavier' grendel bullets with 4895?

I use H4895 for 120-123gn. For example, 28.5gns for the 120NBT. I don't load anything heavier in the Grendel, the case is too small.

[bearmn56]

Hodgdon's "Extreme" powders are virtually cold proof. H4895 and H322 are both good candidates...and are both extreme powders. H's reloading website shows a max load of 26.6 H322 with a 123gr bullet at 2434fps. Sierra lists 25.4 H322, 120gr bullet for 2400fps. 27.4 H4895 gives the 120gr bullet 2500 fps. One could use H4895 with the 129-130gr bullet by reducing the charge by 15% and working up. Probably the same approach could be used for H322 and the 129-130gr bullets. Good Shooting.

[GSPHunter]

gofast,

I've been very happy with the temp stability and performance of AR-Comp with 129ABLR and 130RDF bullets. I lost my notes due to a computer crash, but seem to recall 26.8 gns of AR-Comp running at an average of 2415FPS (20" Faxon) at 70F and 2423FPS at -25F last winter. That was letting rifle and ammunition cold soak for an hour, but keeping the magnetospeed display warm. I seriously doubt it actually is faster, and it maybe that the bayonet shrunk a little in the cold....But for me, AR-comp has been the best combo of speed and stability. Anything over 130gns and it hits the wall pretty fast though.....

[delt475]

H4895 is single-based so more temp stable than double-based powders. I use it for heavier projies.

Varget is another single-based powder but is arguably too slow for typical Grendel length barrels.

RL17, AR-Comp and CFE are all double based so more susceptible to temp changes. AR-Comp is RL15 reformulated but ended up slower than 15, more like Varget's speed.

I find this chart helpful http://www.adi-powders.com.au/powder-equivalents/

Kind of strange how that chart doesn?t have LilGun on it. Unless I?m missing it, I didn?t see it listed. I know it?s the same burn rate as H110, 1680 and 4227.

[BobinNC]

A Couple of points:

1) The ADI chart that some find so helpful, does not have the burn rates for the 3 powders you listed: RL17, AR-Comp, and CFE223.

2) Maybe you made a typo, but AR-Comp is NOT slower than RL-15, and Alliant's own data supports it being quite a bit faster.

223 Rem Max Loads:

77 grain Sierra HPBT

AR-Comp 22.1 grains 2757 FPS
RL-15 24.1 grains 2783 FPS

260 Remington Max Loads:

120 Grain Speer SP

AR-Comp 33.8 grains 2688 FPS
RL-15 39.0 grains 2819 FPS

Source Data:

https://www.alliantpowder.com/resources/catalog/2017/2017_Alliant_Powder.pdf

Unfortunately there's no Alliant data for the 6.5 Grendel, but I doubt that AR-Comp would somehow magically turn out slower than RL-15 in the Grendel.

It seems it is indeed faster than RL-15 based on relative load data, and that clearly places it in the discontinued RL-12 and Norma 202 burn rate ballpark. Both of whom have a close relationship to newish AR-Comp, since all of them originally were developed in Sweden by Norma.

For those that remember Alliant discontinued RL-12 because they said it was too close to RL-15 burn rate wise, even though it was listed as faster burning on almost every burn rate chart I've ever seen. In addition, RL-12 was listed as being the most temp stable of all the Reloader series of powders.

temp sensitivity.jpg

[Klem]

Bobin,

I think you are referring to me...

Thanks for pointing out my error. I incorrectly listed 15 as being slower than Comp, but it's faster. I was referring to this source of info at the time; Accurate Shooter.

My premise is that double-based powders are more temp unstable than single-based.

Yes, the ADI chart is incomplete but I like it for two reasons. It lists burn rate comparisons across competitors. Otherwise you have to go by what individual shooters say on forums. The other reason is that it's a ready-reckoner of what Hodgden sells in the US and where it comes from. ADI only makes single-based powders. If a Hodgden powder has an ADI equivalent then it's a single-based powder. Alliant powders are mostly double-based. Both ADI and IMR make powder to the 4895 specs, but they use different manufacturing processes so H4895 and IMR4895 are not the same powder.

Looking at your temp stability chart it does seem that all powders above '1' (less temp stable) are double-based, and all those below '0.5' (more temp stable) are single-based. That Alliant (double-based) powders are mostly above '1', while ADI (single-based) powders are below '0.5'. That H4895 (single-based) is below '0.5' and IMR4895 is less temp stable. I don't know if IMR4895 is single or double-based.

[grayfox]

The story on AR comp (as I recall from a mfr discussion) is that they wanted to create an "RE-15" powder but with temp stability... hence AR comp. However as it turned out ARC came out a little faster than RE15 when the temp stability ingredient was added.
I like ARC for the 123 Hornady's, it works well for me and I hope its stability will be an asset this fall in the woods.
My 16's are running about 2430 with it and my 20" is about 2505, all with single digit SD's.
I can do less than 1"/100 but most times I seem to be a 1.25 shooter average with my ARs.