Perplexed: Part II

[BobinNC]

Well Part 1 was certainly exciting. We got some excellent input, and some not so excellent input . But that's just how it is on the internet circa 2019.

My next candidate for exploration is a bit more elusive, and considerably more expensive (when considering hazmat fee's). That alone, plus low to negligible visibility, could really answer my question, in and of it's self quite nicely.

Undeterred by answering my own question, here is the next candidate for reloading examination:

"Why isn't Accurate Powder 2495 not more popular among Grendel aficionado's"??


A-2495 is a single-base, extruded rifle powder. When you look at relative burn rates ( chart below) A-2495 is on the same burn rate line as: TAC, RL12, N202, & H335. So A-2495 appears as if it's really right in the sweet spot for launching 120-123 grain bullets from little Grendel cases.

As far as it's temperature stability I got bubkas. One would hope that it's a stable as H4895. But hope is not a plan.

In fact the only real live Grendel data point I have is this one: https://www.shootingtimes.com/editor...el-shine/99645

In that article the author launched a Berger 120 HPBT @ 2551 FPS (Note: 22" barrel) with 27.5 grains of A-2495. That was good for a 0.22" group. Well that certainly got my attention.

I'd like to tell you my own results, but none is to be had locally, though I do have 2 lbs on order with my local gun emporium.

In any event, let me know what you think, or if you ever tried the elusive A-2495.

Thanks,

Bob


Reference Data:

http://www.accuratepowder.com/wp-content/uploads/2010/12/burn_rates.pdf

http://www.t2ammo.com/data/_uploaded/file/Techniek/Powder%20Burn%20Rate%20Chart.pdf

http://www.65grendel.com/forum/showthread.php?11196-Powder-Burn-Rates-and-Temp-Sensitivity

[VASCAR2]

I remember a couple threads discussing Accurate 2495 and using the search feature found these two threads.

http://www.65grendel.com/forum/showthread.php?16423-Accurate-2495

http://www.65grendel.com/forum/showthread.php?9033-reloading-with-ppu-brass

I have never seen Accurate 2495 on the shelf to purchase. I haven't tried to order A-2495 mainly because I have several combinations to try with bullets and powders I currently possess. My time the last couple years to shoot/reload has been curtailed by other priorities. Availability and price plus the lack of current load data for A-2495 surely has restricted it's use in the 6.5 Grendel. It may very well be suitable powder for the 6.5 Grendel and I'd sure would be intersted any results with A-2495.

Sierra's recent reloading data list A-2495 with 120 grain bullets start load 24.7 max load 27.7 grains velocity approximately 2450 FPS out of a 24" barrel/universal receiver. Sierra list a max load od 27.6 grains with 123 grain SMK using Winchester small rifle primers. Sierra also list A-2495 with 130 grain bullets with a max load of 26.6 grains approximately 2350 FPS.

I'm unaware of any other published data on A-2495 and these results are similar to other commonly used powders. Potential accuracy and temperature stability would be interesting to see.

[centerfire]

Bulk density and burn rate. A2495 is too bulky to make speed in Grendel with lighter bullets and too fast to make speed with 120gr+ class bullets. Same as H4895. It may be a good option for 130gr class bullets.

[Kswhitetails]

^^ What he said.

[Klem]

Bobin,

Probably because there are a lot of other equally suitable powders that are more readily available. Not to say 2495 wouldn't do a good job but I have never seen it on the shelves so never used it.

Powder equivalent charts never seem to be perfect and as we know finding the right one also depends on barrel length and the trade-off between energy and temperature stability (single vs. double-based powders). For example, your 12ammo chart lists H4895 and IMR4895 as the same. IMR4895 is made in Canada and H4895 is made in Australia to the same brief but they use different manufacturing processes to achieve similar, but not the same powders. You cannot substitute your favourite load between the two powders. 12ammo also lists H4895 as faster than AR2206H, but they are the same powder. AR ('Australian Rifle') is the retail brand of the factory that makes H4895. Hodgdon buys the powder in bulk, ships it to the US and re-badges it for the US market with more familiar branding. My point is I would be cautious assuming those charts are anything more than almost right.

I imagine as a single-based powder 2495 will be similar to other single-based powders as being more temp insensitive than double-based powders, but I don't know this for sure.

Quickload lists 2495 near the top of the most efficient powders for a 19" barrel and the 107SMK. In theory this suggest it will do really well...if you can find it.


(QL is not definitive either as it lists double-based powders as more efficient as single-based. DB tend to be more energetic than the same volume in SB, so more velocity. But by focussing on velocity QL is ignoring the stability of single-based powders).

[centerfire]

Bobin,

Probably because there are a lot of other equally suitable powders that are more readily available. Not to say 2495 wouldn't do a good job but I have never seen it on the shelves so never used it.

Powder equivalent charts never seem to perfect and as we know finding the right one also depends on barrel length and the trade-off between energy and temperature stability (single vs. double-based powders). For example, your 12ammo chart lists H4895 and IMR4895 as the same. IMR4895 is made in Canada and H4895 is made in Australia to the same brief but they use different manufacturing processes to achieve similar, but not the same powders. You cannot substitute your favourite load between the two powders. 12ammo also lists H4895 as faster than AR2206H, but they are the same powder. AR ('Australian Rifle') is the retail brand of the factory that makes H4895. Hodgdon buys the powder in bulk, ships it to the US and re-badges it for the US market with more familiar branding. My point is I would be cautious assuming those charts are anything more than almost right.

I imagine as a single-based powder 2495 will be similar to other single-based powders as being more temp insensitive than double-based powders, but I don't know this for sure.

Quickload lists 2495 near the top of the most efficient powders for a 19" barrel and the 107SMK. In theory this suggest it will do really well...if you can find it.
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(QL is not definitive either as it lists double-based powders as more efficient as single-based. DB tend to be more energetic than the same volume in SB, so more velocity. But by focussing on velocity QL is ignoring the stability of single-based powders).

I'm not disagreeing with you, I think you're right, but if you trim back the max fill % some of those powders drop off the list. A2495 shows 104% on your chart and would be a pretty compressed load IRL. Despite some of QL's short comings, the fill percentage is usually accurate. The velocity predicted would not only be slower than what is predicted but you'd more than likely also have to use less powder to keep from ringing bullets or ending with growing cartridges.

[Klem]

Centrefire,

I set the parameters at 104% as this is the max % I use in reloading. I don't get the problems you list at 104%. Yes, I would prefer it to be 100% but there's no familiar feel of powder crunching up to 104%. I've been using this 104% as my max for several years without issue.

As for QL predicted velocities...

[HuntTXhogs]

Will Part III be primers

Part VI - brass

....

Never tried accurate 2495, the temp stability being bubkas also holds be back

[BobinNC]

Will Part III be primers

Part VI - brass

....

Never tried accurate 2495, the temp stability being bubkas also holds be back

Nope, 2 parts is all. The thing is I don't know if it's temp stable or not. The only way to be sure is to get people to try it so we have data. You get good data by generating interest. Which also explains why I made this post......

[plainsman456]

Have not seen a lot of powders that i have read about here locally.

So goes the reloading data.

I have gone off on my own before and it was a fun journey.

I keep looking.

[VASCAR2]

A few years ago it was very difficult to find any powder to load so I bought some VihtaVuori. Viht is a little expensive but it was on the shelf. I know Viht is a popular powder in Europe and I bought some N-130 and N-135. This powder metered well and was accurate in 5.56/223 and the 6.5 Grendel. There are several Viht powders suitable for the 6.5 Grendel but I haven’t purchased any since other powders are available. It is an advantage and a disadvantage that the 6.5 Grendel uses many of the same powders as the 5.56/223. There was a drought on powder several years ago attributed to several events.


It was over five years before Accurate 2520 came back on the market and Win 748 was no where to be found. Varget powder was in so short supply and if found the price was high and sold out quickly.

Currently in my area I usually can find CFE223, LeveRevolution, IMR8208XBR, BLc2, Tac and H-335. More recently I’m seeing Benchmark and AR Comp as well as Accurate 2230/Xterminator, 2520 and Win 748.

One thing I like about the 6.5 Grendel is it is capable of using bullets from 85 grains to 130 grains and 140 grains if you don’t mind lower velocity. There are numerous powders which can be used in the 6.5 Grendel which is an advantage if supply dwindles.