Reloder 15 - Temp sensitive?

[PawPaw]

Reading another thread, I saw this posting and wondered about the temperature sensitivity of Reloder 15.

Was using RL-15with very good results, till it gets warm out. To temp sensitive for me

Yet, if we go to the Alliant website, we find that:

Selected as the powder for U.S. Military's M118 special ball long range sniper round.

Thus, the questions: Is Reloder 15 temperature sensitive? Why would the Army pick a powder that might be used in the heat of a desert and the cold of the Arctic if they were concerned about heat sensitivity?

 

[AllenJ]

Alliant states that RL15 is "Consistent at all temperatures". I'm wondering what your forum poster did to come to his conclusion?

 

[Marco Califo]

Why would the Army pick a powder that might be used in the heat of a desert and the cold of the Arctic if they were concerned about heat sensitivity?

The army use double base spherical (ball) powders in almost all military loads. All military surplus bulk powders are ball powders: 844, 846, 867, 872. There is a common misunderstanding that ball powders are too temperature sensitive. I think that is BS, inflated with temperature sensitive hot air.

RL15 is a single base extruded powder and is supposed to be less temp sensitive. However, this difference never stopped (or even slowed down) the military adoption of ball powders. It is used in the 7.62 M118 175 gr LR sniper loads only.

 

[Adamantium]

All military surplus bulk powders are ball powders... ...RL15 is a single base extruded powder and is supposed to be less temp sensitive.

Reloder 15 is a double base powder, in fact I think all current Alliant powders are double base powders. IMR 4895 is an extruded powder, not ball, and can be bought as a surplus powder.

OP: Now mind you this data comes straight from Hodgdon but here is a comparison of Varget, Win 748, Reloder 15, Vit N140, IMR 4064 and AA 2520 in 308 Win.

http://www.hodgdon.com/smokeless/extreme/page2.php#top

 

[tobnpr]

Thus, the questions: Is Reloder 15 temperature sensitive? Why would the Army pick a powder that might be used in the heat of a desert and the cold of the Arctic if they were concerned about heat sensitivity?

Yes, Reloader 15 is not an "extreme" powder, an is temp sensitive.

Far as why the military uses temp sensitive powder- dunno...

But I can tell you that I recently saw an interview with one of the record- breaking snipers (longest confirmed kill) and he specifically mentioned- as I've heard others do- that he left the rounds in the sun to cook and raise velocity/pressures in the Afghanistan sun before shooting.

 

[Jimro]

If I told you that between IMR 4895 and IMR 4064 that the latter was LESS temp sensitive than the former some people would feel the need to argue. The difference across a 100 degree F spread for 4064 is about 20fps for match loads in a 30-06, which is very good performance for such an old formula. Why the military continued to use 4895 in M72 match loads until they stopped purchasing 30-06 is beyond me.

So RL-15 is "temp stable" enough to be in the same class as 4064 if not better, being a good old stick powder.

As far as Hogdon's "Extreme" lineup, they are not truly "temperature stable" they are just LESS affected by heat than some of the older formulas. Is the 10 to 15 fps difference between Varget and 4064 enough to justify switching? Not in my book, as even some match loads have that much variation in extreme spread within the same lot of ammo.

Reloader 15 is good to go. For what it is worth once ATK took over the Lake City plant RL-15 was nominated to replace the previous powder... I think it has more to do with ATK making a profit than an advantage to the end user. Sniper instructors still teach students to plan on 1 MOA difference per X number of degress difference in temperature from their zero temperature. If I recall it was 20 degrees a few years back, but that was due to atmospheric density and not muzzle velocity variations.

Jimro

 

[mrawesome22]

Think I saw that show. In that same show, a Canadian sniper was explaining how he borrowed some 50bmg off a U.S. soldier because it is loaded hotter than the Canadian stuff.

But I digres. All powder is temp sensitive. Some less than others, some more than others.

Sent from HenseMod6.

 

[FrankenMauser]

There's no reason to declare a powder 'temperature sensitive', due to a single shooter's experience. ....just like there's no reason to declare a power 'temperature insensitive', due to a single shooter's experience.


I haven't done much with RL-15, but I have done a lot of testing with RL-19.

I found RL-19 to be incredibly stable, much more so than even Hodgdon's "Extreme" powders.
So, I would be willing to bet I would have the same results with further testing of RL-15. But, you never know.


Something that may be of interest here, is some information from the Ramshot website:

What is the real story behind temperature stability?
Most of our powders are not insensitive, and will show some effect at hot and cold temperatures.

However, we test at -40F and +125F and the deviation in most cases are ca 3% to 5% at these extreme levels. Therefore most shooters do not notice much difference under normal practical hunting conditions.

More elaboration on the subject:

Complete temperature stability can only be achieved with tubular extruded powders designs, either with double base (NG) and/or with other coating technologies.

Because the ballistic performance at extreme temperature is completely dependant on the specific combination, it is very difficult to quantify and qualify.

Our standard powders perform very well at extreme temperatures, and usually pass the strict military requirements by a large margin.

This is a subject that often fraught with misconceptions and inaccuracies.

The term is used loosely by manufacturers without qualifying the subject, and is obviously exploited for marketing purposes and perceptions.

The facts are:

Although powders can be improved, it’s really only possible with advanced coating procedures and additives which increase the cost.
A particular powder can be improved re temperature stability for certain combinations, within a certain envelope which is specific to the following three main parameters/aspects
The caliber.
The weight of the projectile/bullet.
The performance level.

If any of these parameters/aspects go beyond or outside the intended ratio/s, the results will change and the performance will sometimes be different.

It is also very important that when a comparison is made, that all conditions re weapon i.e. components primer, case, bullet and the velocity are equal, and preferably done at the same time on the same day.

So, it's quite possible that my own experience with Ramshot Hunter (incredibly temperature sensitive during my testing) could by one of the "outside the intended ratios" scenarios; while my experience with RL-19 (and the military's experience with RL-15) happens to be an "within the intended ratios" scenario.

 

[FrankenMauser]

Digging a little further today, I reaffirm my comments about expecting RL-15 to react very similarly to RL-19.

RL-7, RL-15, RL-19, and RL-22 are produced by Nobel/Bofors, in Sweden.
So, it's reasonable to expect similar performance.

RL-17 is a standout, and is produced by Rheinmetall/Nitrochemie, in Germany.

Although the same burn rate is targeted for "equivalent" powders, Norma-specc'd powders from Nobel/Bofors use cotton fiber as the nitrocellulose source; while those sold to ATK for the Reloader brand use wood pulp as the nitrocellulose source.
"Equivalent" (but not interchangeable) powders: RL-15 ~=~ Norma N203b. RL-19 ~=~ Norma N204. RL-22 ~=~ Norma MRP.

 

[PawPaw]

I haven't done much with RL-15, but I have done a lot of testing with RL-19.

I found RL-19 to be incredibly stable, much more so than even Hodgdon's "Extreme" powders.

RL15 is my go-to powder for the .308 and RL19 is my go-to for the .30-06, bolt gun loads. I've gotten some great results with Reloder 19 and 150 grain bullets in the -06. Don't shoot them through a Garand, though.