Looking for something slightly faster than H4350...

[Ringostar]

Are you looking for higher velocity or faster burn rate. A faster burn rate might not get you higher velocity, but a slower burn rate might. i notice in Hodgdon's load data that for some cartridges, Hybrid 100V gives higher velocities with a lot less pressure than H4350 and H4831sc.

 

[savageshooter86]

What about H4895? what bullets are you shooting. Might work well for 200 gr bullets.

 

[MagnumManiac]

I normally don't recommend powders, but, why have you not considered Varget in your 308? The difference in speed will be little, and the smaller granules/kernels will occupy less space.

I would give it a try, can't hurt anyway.

Cheers.

 

[rardoin]

Are you looking for higher velocity or faster burn rate. A faster burn rate might not get you higher velocity, but a slower burn rate might. i notice in Hodgdon's load data that for some cartridges, Hybrid 100V gives higher velocities with a lot less pressure than H4350 and H4831sc.

In a 6.5 Creedmoor I found Hybrid 100V to give me about 80-90fps more than an equivalent load of H4350 with some of the best grouping shot in that barrel/primer combo...but I was concerned about it not being a relatively temperature insensitive powder so I stopped development when H4350 became available to me again. If I was loading hunting rounds it would be fine; for competition at MR+, I had concerns.

 

[Laurie]

N150 is widely used in 308 for FTR with the 185gn Berger Juggernaut bullet and is ideally suited to this combination. I've long used it too with 155s in the 308 for short-range matches - superb precision and small ES values but a bit short of velocity. (Think ~2,900 -2,925 fps from a 30-inch barrel, or 150 fps down on potential VarGet / H4895 loadings).

However, I have recently seen some use of N150 with 155s in seriously compressed loadings at just over the 50gn level in small primer Lapua 'Palma' brass and a fairly long-throat chamber. This gave the same excellent results as I'd obtained with lighter loads, but with MVs in the high 3,000s fps level. This powder has long been one of my favourites, especially as Vihtavuori prices and supply reliability are much better than those of the Hodgdon range in the UK. It is a very stable propellant that is IME consistent from lot to lot. It gets a lot of use here in the mid-size 260s too.

It should be noted though that we in GB rarely worry about the effect of temperature changes on pressures, so this could be an issue in North America.

The N500 series powders were very widely used in GB FTR some years back, but much less so today. This is partly because alternatives have been found using N100 grades that only give a small amount of MV loss, but also because of unacceptably rapid throat erosion. In the very early days of FTR, three of us sourced identical Bartlein slow twist barrels and shot 155gn Lapua Scenars at 3,075-3,100 fps in large primer Lapua brass over N540. My two friends had their barrels pack up within a month or two of each other at not much over the 1,100/1,200 round mark. I had my rifle rebarrelled to a 10" twist Broughton at around the same time even though it was still performing well as I wanted to use the then new 185gn Juggernaut (mainly over N550). The slow twist barrel was put on one side. Quite by chance, it was dug out a week ago and borescoped to see if it was fit to be reused in an upcoming project. No, it was completely finished at 1,100 rounds of exclusively N540. Remember too, we don't string-shoot in GB F-Class, and allied to generally lower ambient temperatures, should see considerably better barrel life than our US friends can expect. At the time, we thought maybe the barrel threesome had used a soft grade of steel, and this may still be so, but we're now more inclined to the extra wear from hot loads with 'high-energy' added-nitroglycerin powders explanation.

 

[cmillard]

imr 4320

 

[Toolbreaker]

If you can get your hands on some of the "old" IMR 4007 powder (I know there was a recall) I believe that would fill your bill to a tee!

What Ben said, here. Since it is discontinued, you might want to see if you can find a decent quantity before trying a 1 lb'er, though. Murphy does like to tease people a little bit, sometimes...

 

[normmatzen]

What Cole said.

I changed my 6BRX from Varget to IMR4320 when Varget became un-obtainium.
I found my loads were exactly the same as Varget with same Mv.
And, it's available.

 

[Lapua40X]

Working incrementally upward in faster powers you run into problems with rifle powder availability.
Then, when you find something that is fairly common on the shelf, the granular variations that affect case capacity becomes the next problem.
VihtaVuori N150 might take you where you want to go.

 

[johnfred1965]

Load density is calculated by weight and not volume. If a case holds 50 grains of water then a 50 grain charge of powder is 100% load density. Smokeless powders typically are denser than water so it is easy to get load densities over 100% and still not fill the case volume.

I was always under the impression that load density had to do with volume in the case, where can I read up on weight calculating density?

 

[JamesnTN]

IMR 4064 works well in the 308

 

[johnfred1965]

I was always under the impression that load density had to do with volume in the case, where can I read up on weight calculating density?

Nevermind, google strikes again! Looks like it is a combination of weight and volume, so I wasn't totally wrong.

 

[Joe R]

I'm looking for a powder that will provide the consistency of H4350, the same kind of ES numbers, that is slightly faster, with out increasing volume. So in round numbers what I'm looking for is a powder to give a similar pressure and velocity of say 50 grains of H4350 but with slightly less volume of powder as H4350. (think of something that is like a really fast lot of H4350)

I had a good load worked up that was right at 100% fill last yr.... Got a new lot of H4350 and oops, now I need nearly a grain more to keep the same MV, but the case is out of volume.

I'm dabbling with N150 right now but it seems to be a bit less dense. It can get to the velocity with less weight, but it seems to take about the same volume, which translates to just a bit too much to get to where I want to be.

Re16 seems to be in the right pressure range but it takes more volume, so it won't work.

Any other ideas?

According to Quickload H-4350 has a heat potential of 3760, N-150 has 3780, Accurate 2495 has 3810, Accurate 4350 has 3850, RL25 has 3810, IMR7928sc has 3850

 

[264WM70]

I have switched to RL-17 for my 284 WIN F Class gun. I am in the process of trying RL-16 in hopes it is more temp stable.

To that end, here is some QuickLoad data on RL-16, RL-17 and H4350.
All three loads are within 6 fps of Mv around 2918 fps with 162 gr bullets in a 28.75" barrel.

Powder Weight fill
RL-16 51.7gr 96.3%
RL-17 51.7gr 89.4%
H4350 53.3gr 98.3%

THESE ARE NOT LOAD RECOMMENDATIONS, JUST RELATIVE DATA!

What does QuickLoad project for N150

 

[normmatzen]

QL says in my 284 WIN N150 needs 52 gr for comparable velocity as my previous post. The fill is 100% and the pressure is sky high!

 

[XTR]

Powder Weight fill
RL-16 51.7gr 96.3%

H4350 53.3gr 98.3%

THESE ARE NOT LOAD RECOMMENDATIONS, JUST RELATIVE DATA!

If this is by volume then this seems to contradict some other posts here from folks trying R16 in 6.5x47 cases. When asked in another thread those posters noted that RL16 required less weight but a greater % fill by volume to get the same velocities.


http://forum.accurateshooter.com/threads/alliant-reloder-16.3905416/page-6#post-36839396

 

[Laurie]

QL says in my 284 WIN N150 needs 52 gr for comparable velocity as my previous post. The fill is 100% and the pressure is sky high!

I'd never use N150 in 284 Win with anything other than very light bullets. I don't even use it in my F-Class long-throat 7mm-08 despite its considerably smaller case capacity. So far as Viht powders go, N160 is my powder of choice for 160/162s in both the 7mm-08 and 284 and N165 for 175/180s in the 284. (I've also had promising results with some severely compressed 175gn SMK / N165 loads in the 7mm-08 which I intend to follow up on.)

(I did try the denser and slower burning N550 variant with the 160gn Sierra TMK in the 7mm-08 and despite some promising initial results, dropped it after failing to get it to perform consistently.)

 

[Laurie]

PS If using QuickLOAD for N160 in these two cartridges (7mm-08 and 284 Win) - don't believe the results! Same thing for the mid size 6.5s (260 and Creedmoor). There seems to be something wrong with QL's standard data entries and I've encountered severe pressure issues with test loads predicted to produce 55,000 psi. (That's with the default case water capacities changed to suit actual fireformed weight and correct COALs just off the lands input.)

When I use QL now to get some starting points for load development with the powder, I use whatever charge weight the program predicts will produce 52,000 psi as my top load for the initial try-out.

 

[264WM70]

If this is by volume then this seems to contradict some other posts here from folks trying R16 in 6.5x47 cases. When asked in another thread those posters noted that RL16 required less weight but a greater % fill by volume to get the same velocities.


http://forum.accurateshooter.com/threads/alliant-reloder-16.3905416/page-6#post-36839396

I was on that thread. The R16 needed less weight to get me to the H4350 velocity that worked in my 6.5x47 but the fill volume didn't change very much. The OP has the same problem I have. With R16 I am having difficulty seating the bullets down where my rifle likes them. With Varget, I can jump 30 no problem but I haven't found a load that will shoot well enough. I need something around H4350 that gives the right burn rate with less fill volume. I believe N150 is what I will try next.

 

[XTR]

I was on that thread. ...

I need something around H4350 that gives the right burn rate with less fill volume. I believe N150 is what I will try next.

This is the whole point of this thread. My current testing says N150 isn't the answer for which we are searching.