SINGLE OR DOUBLE BASED POWDER.

[paul T]

Interested in hearing reloaders view with which powder offers better acuracy potential for Long range shooting with single or High energy double based powders, E.g for 308 win Vit n140 V N540, I know the double based powders offer more vel with reduced pressure but for some reason many benchrest and F-class shooters seem to prefer the single based powders e.g n160-243 win n140-Varget for 308 over the double based propellents, anyone tried both whith their loads and could share what they have experianced, thanks.

 

[Ratwhiskers]

Re: SINGLE OR DOUBLE BASED POWDER.

Paul.

This may or may not answer some of your question. I pulled this letter from another forum some time ago, as I found that it led me to turn away from using double base powders for my applications. I have also found that in some loads people get no desernable benifit from double base powders.

Regards.

Ratty.
....

....We are happy to be able to supply reloading powder for all quality concerned shooters like you.

Bore and throat erosion is really dependent on powder composition. The important parameter is flame temperature, which is unfortunately immeasurable quantity. Based on thermodynamic calculation, and long experience it is well known fact that higher energy content (i.e. heat of explosion) leads to higher flame temperature and higher throat erosion.

Easiest method to improve ballistic performance is to add nitroglycerol in powder composition. These powders are called double base powders. As you have heard, these powders tend to cause more barrel and throat erosion compared to single base powders. This difference is clear but it is, however impossible to quantify as for example as numbers of rounds to reach same erosion level.

All Vihtavuori N100 (N105...), N300 (N310...) powders, 3N37 and 3N38 are single base powders. These products are made with best available raw materials and manufacturing methods to get maximal performance you can get without using more erosive double base composition. Therefore, these Vihtavuori products cause less erosion than most of other competing powders. Especially high nitroglycerol contents (and thus erosion) are used in spherical powders (ball powders) and some US products.

Among Vihtavuori product line we have only five types we call N500 (N530 ... N570) which are by composition double base powders. N500 rifle powders contain small amount of nitroglycerol to add a bit more performance required mainly for extremely long distances. Even with these products we have added a special additive as well kept nitroglycerol content rather low in order to minimize the barrel erosion effect.

So, my opinion and advice is to keep barrel and throat erosion on minimum by using only single base powders like Vihtavuori N100, N300 and 3N.

Best Regards,

Mikko Vuoristo
EURENCO Vihtavuori Oy

 

[jimurphy]

Re: SINGLE OR DOUBLE BASED POWDER.

The double based powders are more temperature sensitive and possibly harder on the bore. The Hodgdon Extreme powders are a popular single based powder for long range shooting.

 

[sharac]

Re: SINGLE OR DOUBLE BASED POWDER.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: jlmurphy</div><div class="ubbcode-body">The double based powders are more temperature sensitive and possibly harder on the bore. The Hodgdon Extreme powders are a popular single based powder for long range shooting. </div></div>

Not always as temperature sensitivity is caused also by grain structure and additives. Same goes for "heat of explosion" which is atleast for Vihtavouri not all that great (difference between single and double based). I'd say double based powders have a specific use when one is chasing FPS (1000m shooting with 155 scenar or GS custom 137/158/163 SP solids). As for why more people don't use it, that would be because most competitors tend to stick to what works and differences are not such that would warrant a fundamental change - powder is usually bought in larger lots so changing that is not a day to day affair.

 

[paul T]

Re: SINGLE OR DOUBLE BASED POWDER.

Thanks for replys, some helpfull info there Ratwhiskers thanks paul.