burn rate ?

[338 Mollett]

Is Re33 slower than retumbo? Thanks!

 

[338 Mollett]

I have Bla Bla data so person come help!

 

[Corey Schwanz]

Based on this chart: http://www.accuratepowder.com/wp-content/uploads/2010/12/burn_rates.pdf that shows RL-25 and Retumbo to be roughly the same rate, and knowing that RL-33 is supposed to be in between RL-25 and RL-50, I would say yes, RL-33 is a bit slower than Retumbo. It may not be by much. Hopefully someone else can find a better chart or listing directly from Alliant maybe?

 

[Milo 2.0]

A friend and I tested the two powders mentioned in a 300 Norma mag. I do believe 33 is slower than Retumbo. But also believe it's a higher energy powder also, so it's behavior pattern may make it hard to prove.
It'll be Friday before I can get friends data, so hopefully you'll have it solved by then.

 

[Joe Salt]

Like Corey said between RL-25 and RL-50. I was using 88 grain of RL-33 in my 308 Baer with 230 OTM's and was getting velocities you couldn't believe.

Joe Salt

 

[jaclthr]

Hello All,

Do you have any data about stability in temp. changes?

Thanks

jaclthr

 

[Lapua40X]

While I would expect the RE-33 burn rate to be somewhere in the neighborhood of Retumbo, I haven't seen anything published that might answer your question.
Have you given any thought to asking Alliant for the info?

http://www.alliantpowder.com/questions/default.aspx

 

[double g]

Slower than retumbo and faster than retumbo at max pressure. DG

 

[338 Mollett]

Thanks boys!I'm armed and dangerous now.

 

[Laurie]

Re33 is a Swiss manufactured powder made by Nitrochemie Wimmins AG and sold in Europe as Reload Swiss RS80. Nitrochemie's comparative powder burn chart (column format, not list) shows Re33/RS80 as one step / line slower than Retumbo and same as Viht N570.

Re33/RS80 is a high-energy powder, that is manufactured as nitrocellulose single-base kernels initially before being infused with a percentage of nitroglycerine as a separate production stage. All RS H-E powders have a nominal 3,990 KJ / Kg specific energy rating (K-Joules per Kilo weight), whilst Hodgdon lists the single-base Retumbo at 3,710 KJ / Kg, so the Swiss product has around 7.5% more energy input for any given charge weight. As most rifle cartridges give ~34-38% energy efficiency, that translates into a higher MV that would give a higher MV such that it would produce a 2.5-3% higher muzzle energy value. That assumes though that b oth powders produce the same overall efficiency and see the same (hopefully 100% or near enough) charge burn before the bullet exits the barrel. That may not apply though.

Being high-energy / containing nitroglycerine, Re33 will almost certainly be more temperature affected than a single base formulation such as Retumbo, and that's before ADI does whatever it does to make the Hodgdon powders 'Extreme' formulations that reduce temperature sensitivity even more. There are certainly a few complaints on this forum about Alliant Re17 which is another NitroChemie manufactured high-energy product from the Reload Swiss range.

 

[dkhunt14]

I shot the RE 33 in my Lapua IMP and at 1600 yards saw no difference in clicks from 40 degrees to almost 0. I haven't shot it in high temperatures because it is a hunting gun. It gives a lot more velocity in my gun compared to Retumbo and H 1000. It also shot better groups at 1000 yards. With H1000 and a 300 Berger I got 2990 and was a little sticky on bolt lift. I got 3170 with R33 and the load was cold yet. I didn't try to see how far it would go because I have first generation Bergers and they start to slump at around 3000. Matt

 

[dmoran]

Being high-energy / containing nitroglycerine, Re33 will almost certainly be more temperature affected than a single base formulation such as Retumbo, and that's before ADI does whatever it does to make the Hodgdon powders 'Extreme' formulations that reduce temperature sensitivity even more.

I shot the RE 33 in my Lapua IMP and at 1600 yards saw no difference in clicks from 40 degrees to almost 0. I haven't shot it in high temperatures because it is a hunting gun. It gives a lot more velocity in my gun compared to Retumbo and H 1000. It also shot better groups at 1000 yards. With H1000 and a 300 Berger I got 2990 and was a little sticky on bolt lift. I got 3170 with R33 and the load was cold yet. I didn't try to see how far it would go because I have first generation Bergers and they start to slump at around 3000. Matt

First, a negative assumption...... (almost bias like)
Second, first hand experience....... (to 1600yds on top of it, from a very experienced long range shooter)

Thanks Matt for sharing your experience !.!.! Good of you..... as always
Donovan

 

[Laurie]

First, a negative assumption...... (almost bias like)

Donovan, please explain why 'negative'?; why 'bias'?

It's a fact, taken as a group, single-base powders are more temperature stable than either true double-based, or added nitroglycerine (high-energy). Some manufacturers even admit it, despite everybody claiming in their marketing material that their propellants are (of course) 100% unaffected.

Here’s what Keith Anderson of Western Powders’ (Ramshot / Accurate powders, all of whose ball grades are double-based) ballistics lab said in a post on another forum a couple of years back:

“All of the powders sold under the Ramshot or Accurate brands meet or exceed the military specification for hot and cold stability. As with anything, some powders are better than others. Single base powders such as Varget can be made to be more temperature stable than double based powders such as Accurate 2520 although there are trade offs to anything. While the nitroglycerin in a double based powder makes it less temperature stable it is the component that makes double based powders cleaner burning and allows them to attain higher velocities and their single based cousins.

“In both the single base and double base lines of powders some powders have better temperature stability than others, Ramshot ‘TAC’ is one of the most temperature stable double based powders available. It is this very reason that so much of it is being used for military applications in both Iraq and Afghanistan. Even under extreme temperatures Ramshot ‘TAC’ will vary less than half what the military will allow.”

FWIW, as I pointed out, Re33 is a slower burning sibling of Re17 (RS80 and RS60, both from NitroChemie Wimmins), made using exactly the same technology and ingredients, and there are a LOT of complaints on this forum on Re17's alleged temperature 'instability' - none from me I may add. Jaclthr asked if it (Re33) was likely to be temperature sensitive - the answer is that the answer is probably 'yes', although everything in this game is relative and potential users have to balance pluses and minuses depending on what they're looking for. The Reload Swiss range including the the two high-energy grades sold under the 'Alliant' name have lots of pluses primarily higher performance and the unique infused throughout the kernel deterrent technology, so there are plenty of reasons for choosing them. I don't see any 'bias' there.

 

[Milo 2.0]

Laurie,
Love your posts on powder, have learned a ton from them. That reply took me aback also.