Reloading data

[shotgunner]

Hi, has anyone got a start /max load for a 6.5x47L 20 inch barrel, using rs62

With nosler BT 120gr

I am struggling to find a load thanks in advance

[BlueBoy69]

There's data in the Reload Swiss manual (link) and on their webpage (link) listing RS62 with a 123 grain Lapua Scenar. You can use this as you starting point.

 

Looking at their data and then plugging this into QuickLOAD results in a pressure and velocity that comes near, but is not the same. Both are predicted higher in QuickLOAD than the Reload Swiss pressure tested load. Even so, I'm not entirely sure why they load so low with this powder and bullet combination, as the max pressure they list is only 2,395 bar (34,740 PSI), compared with 3,200 to 3,950 bar (46,500 to 56,500 PSI) for most of their other 6.5x47L loads? Even going by QuickLOAD, you can go to a 102% fill (the max fill listed by Reload Swiss only being about 92.6%) and still stay within the safe, but not max pressure levels.

 

In either case, RS62 does seems to be a little slow for this particular bullet/case, but you may, or some other person, have already got it to work.

[shotgunner]

Cheers BB 69 for the information , wandering if it's going to be the right powder for my length of barrel and light bullets

[palmarifle]

My Favorit Load 41,5 grs RS 62, feet my one with 41,5 behind Lapua Scenar 109 "and" 123grs! Same results on up to 300 Meter - Greetings from Germany - Frank

[BlueBoy69]

Cheers BB 69 for the information , wandering if it's going to be the right powder for my length of barrel and light bullets

 

I think it should OK, just you might need to add some more in, as per what 'palmarifle' above mentions for his loads.

 

As always, carefully work up your load.

 

Personally, I use the devil's powder, RS60 with my 123 grain and heavier loads, but it's taboo to use it here. Patent and other reference material on for RS60, such as its material safety data sheet (MSDS), states it contains about 16% nitroglycerin (NG), which compares quite closely to many double base (DB) ball propellants, but nowhere near Vithavouri's and other manufactures DB high energy content propellants that contain up to and greater than 30% NG. Its NG level is around the same as that stated for the often now recommended, due to European REACH policy, IMR Enduron powders (their MSDS stated an NG content of 5-15%), but heigh-ho and c'est la vie and all that.

[shotgunner]

Cheers for the information,I am currently loading r15 37.7grs ,using 123 amax , in my other 6.5x47L 26 inch barrel

But was wanting to change powder before it's band from the UK,

And set up a new load,

For my stalking rifle,

[shotgunner]

Cheers for the information,I am currently loading r15 37.7grs ,using 123 amax , in my other 6.5x47L 26 inch barrel

But was wanting to change powder before it's band from the UK,

And set up a new load,

For my stalking rifle,

[BlueBoy69]

Cheers for the information,I am currently loading r15 37.7grs ,using 123 amax , in my other 6.5x47L 26 inch barrel

But was wanting to change powder before it's band from the UK,

And set up a new load,

For my stalking rifle,

 

Hmm, as RL15 is stated in Alliant's MSDS to contain diisopentyl phthalate, then it well may be banned from import as a reloading powder under the REACH directive. So yes, best to find something that is REACH-compliant to use instead.

[Laurie]

All Alliant rifle powders are REACH compliant, (can't comment on pistol / revolver grades).

 

The issue with RS60 (and RS40 / 52 / 70 amongst others) is the combination of infused nitroglycerin and Nitrochemie's EI patented deep infused deterrents technology. The latter gives a much increased period of controlled early burn so flattening the early part of the time / pressure curve and extending the period of maximum pressure and heat. That combination is a good thing for performance but where maximum available advantage is taken of it, increases barrel wear dramatically over another high-energy type using conventional coated deterrent technology.

 

It gives higher MVs for lower pressures allowing higher charges. But as there are no free lunches and the mix allows an increased heat-energy input, and given that an efficient cartridge such as 6.5X47L has an internal ballistic efficiency rating of around 35%, then nearly two-thirds of the additional energy being used goes into muzzle blast, noise, and most of all waste-heat. With the extended length of controlled burn, the area of barrel affected by peak temperature and pressure is significantly extended too.

 

That's not to say that there is anything at all wrong with these powders, far from it - just as long as people realise there is a trade-off involved. Some cartridges' internal ballistics ratios are such that very large performance increments are achieved with maximum pressure EI technology propellant loads - 284 Win / Shehane and 6mm Tubb XC with Re17 / RS60 are outstanding examples, the XC getting another 200 fps with heavy bullets. That 7% MV increase may be bought though at the cost of a reduction of barrel accuracy life by a third or more.

[BlueBoy69]

All Alliant rifle powders are REACH compliant, (can't comment on pistol / revolver grades).

 

The issue with RS60 (and RS40 / 52 / 70 amongst others) is the combination of infused nitroglycerin and Nitrochemie's EI patented deep infused deterrents technology. The latter gives a much increased period of controlled early burn so flattening the early part of the time / pressure curve and extending the period of maximum pressure and heat. That combination is a good thing for performance but where maximum available advantage is taken of it, increases barrel wear dramatically over another high-energy type using conventional coated deterrent technology.

 

It gives higher MVs for lower pressures allowing higher charges. But as there are no free lunches and the mix allows an increased heat-energy input, and given that an efficient cartridge such as 6.5X47L has an internal ballistic efficiency rating of around 35%, then nearly two-thirds of the additional energy being used goes into muzzle blast, noise, and most of all waste-heat. With the extended length of controlled burn, the area of barrel affected by peak temperature and pressure is significantly extended too.

 

That's not to say that there is anything at all wrong with these powders, far from it - just as long as people realise there is a trade-off involved. Some cartridges' internal ballistics ratios are such that very large performance increments are achieved with maximum pressure EI technology propellant loads - 284 Win / Shehane and 6mm Tubb XC with Re17 / RS60 are outstanding examples, the XC getting another 200 fps with heavy bullets. That 7% MV increase may be bought though at the cost of a reduction of barrel accuracy life by a third or more.

 

As mentioned Shotgunner, taboo!

 

I've researched this in detail and the difference in nitroglycerine (NG) content between some of the taboo powders and those that are supposedly fine is often a few percent, not tens of percent as in high-NG content double base (DB) propellants.

 

Also virtually none of the manufacturers state the propellant flame temperature which is the primary deciding factor in barrel erosion, with pressure coming second (see later equation). All they state, if you are lucky, is the heat of explosion and this cannot be equated directly (easily) to the flame temperature. It is possible to convert one to the other, but this requires additional details, such as the chemical composition of the propellant and its combustion products, which are even harder to find.

 

erosion ≈ (T_ex)⁷ × (p_max)⁵ × (m_c)^1.5 × (v_o)^1.4

T_ex= flame temperature, P_max= peak pressure, m_c = charge mass, and v₀ = muzzle velocity.

 

The DB propellant is of course affected by the type of nitrocellulose (NC) used in its manufacture. Highly nitrated NC having a highly energy content and flame temperature that lower nitrated NC. Never be fooled by the statement that NC is of one type only, nor that is energy content or flame temperature is of only roughly one value. Similarly and ignoring the shape (morphology) of the grains, no two single base propellants are the same, they all have different properties. This due to the type of NC used and the additives, which may be inert, or contribute to the combustion process. The additives being items such as the plasticizer and stabiliser mix, along with a coating of graphite to lower the effect of static charges on the grain. Additional common additives may be a flash suppressant and/or decoppering agent.

 

The grain shape of RS rifle powders are single perforated tubes, as are many other powders. This leads to a generally neutral burning powder, i.e., its surface area remains roughly constant through the ballistic cycle. This because, as the outside surface area decreases, the inside increases. In RS’s extruded impregnated (EI) powders, a shallow outer layer the grain surface (included the central tube) is impregnated with NG, this then coated with a deterrent and then graphite. Their propellant EI formulations are commonly almost exactly the same, other than the deterrent depth/type and the grain size. When the grain burns, the surface (external and within the tube) regresses, the deterrent layer is first consumed, then the thin NG impregnated layer. Once this NG layer is consumed, all that is left is the generally lower energy nitrocellulose, plasticizer and stabiliser mix.

 

The tailoring of the deterrent layer controls when the propellant starts burning and where the majority of the grains are when they start to combust. As with most granular propellant based systems, the propellant is moved and compressed by both compressive pressure pulse from the primer ignition and the gradual pressurisation of the grain bed by the gases produces by the portion of the grain that is already burning. This results in the projectile (bullet) being pushed from the chamber(case) before some of the propellant has yet combusted. For RS EI propellants, the deterrent, the NG layer and this movement means the combustion of the propellant is the same as most common propellant. This results in the propellant burning and achieving its maximum pressure at a distance further down the tube (barrel). It also means that time period that the peak pressure is present is longer too. Simplify the area under the pressure/time, or pressure/motion) curve graph is larger, so more work is being done in the same volume of the barrel. It is this additional work and hence energy deposited within the bore of the barrel that potentially causes the increased erosion, not simply increased flame temperature or heat of explosion.

 

For note, in general, around 30% percent of the propellant energy ends up in the projectile (its translational (velocity) and its rotation energy), 45% in the powder gases (the velocity and temperature) and the rest goes into heating the barrel, partly by direct heat transfer and partly through friction. Obviously as the tube length increases, less and less energy ends up in the exiting gases, this ending up in the projectile and barrel.

 

As mentioned in previous posts, the movement of the propellant bed and hence projectile can, in some cases, has serious effects on the internal ballistics and accuracy of the system. This proved and covered in detail by many US Army Research Laboratory and other labs research papers, even if people here choose not acknowledge it.

[shotgunner]

Thanks for the information, a bit to much over my head I'm afraid,

I have just had my T3 rebarelled in 6.5x47L

Its main use is as a stalking,foxing rifle,

I don't want to use the barrel burning powders

Just a suitable replacement, Powder, for the RL-15 / varget

Thanks for all the information,

Received, wanted to use NOSLER BT 120gr

I have bought some rs62 powder, but with having a short barrel 20" ,and light bullet 120 gr may have to change powder or bullet wieght,

Any advice or information is much appreciated thanks,

[Laurie]

RS62 is a bit slow burning for your combination, but give it a try. You'll need a case-full to get to full working pressures.

 

The RS equivalents for Re15 and VarGet are RS50 and 52, especially the latter which can be used as an excellent replacement in most cartridges. If you don't want a high-energy EI type (ie RS52), RS50 would be the one to try. But try your 62 first.

[shotgunner]

Cheers Laurie

I will give the rs62 a go and work up a load ,fingers crossed

[shotgunner]

Hi Laurie

I have changed the rs  62 Powder to rs 50 

Can anyone give me a start and  max load for a 6.5x47L with a 20inch barrel for nosler BT 120g using rs 50 thanks in advance ,