Kynamco powders

[GerardV]

After 9 months of waiting, my Charles Lancaster boxlock double has finally arrived in the country. The rifle comes with two barrel sets chambered in .470 NE and .375 H&H, both regulated for modern Kynoch ammunition.

As Kynamco has sadly gone into administration, I am left with the prospect of developing equivalent handloads for both.

Does anyone know what powder Kynamco used in their factory loads for these two cartridges? Or a close equivalent?

I have AR2209, 2213SC and RL-15, along with Woodleigh projectiles and Norma brass so between then I'm sure I can find something that will work, but if I can minimise shooting a 470NE off a bench for load development then all the better.

 

[Tintin]

Congrats Gerard. What an exciting day.

I can't advise in the Kynamco powder, but I assume you have a copy of Graeme Wright's book.

Literature - Woodleigh Bullets

Woodleigh Bullets - Premium Bullets for All Game

www.woodleighbullets.com.au

Did you get a BCH trip in yet?

 

[GerardV]

Congrats Gerard. What an exciting day.

I can't advise in the Kynamco powder, but I assume you have a copy of Graeme Wright's book.

Literature - Woodleigh Bullets

Woodleigh Bullets - Premium Bullets for All Game

www.woodleighbullets.com.au

Did you get a BCH trip in yet?

Cheers Tintin, yes I do have a copy of Graemes book.

No luck on the BCH trip thus far as I moved to QLD. Maybe sometime I'll make it back up there but unfortunately it's unlikely to be this year with my work schedule.

 

[Pondoro]

RL15 is very much like Vithavuori N150.. I load 90 grains behind a 500 grain Woodleigh ..my rifle is a .470 Krieghoff.

A buddy load 91,5 grains behind same bullet in an identical rifle..his regulate best with that load...give 2150fps.

These fastburning powders give significantly less recoil than the more slow burners..and the same velocity.

 

[Pondoro]

A friendly warning on Kynamco ammunition.. I have personal experience with it in .416 Rigby, .500 Jeffery and .475 3.25NE.

The .416 and .500 was clearly overloaded to the point that I had to pry the bolt open..both calibers.. Scary..stopped using it. (Norma factory in both those calibers are ok..).

The .475 load is also stout, give 2158fps from 23" barrels but regulate well in my pre-WW1 rifle.

 

[GerardV]

RL15 is very much like Vithavuori N150.. I load 90 grains behind a 500 grain Woodleigh ..my rifle is a .470 Krieghoff.

A buddy load 91,5 grains behind same bullet in an identical rifle..his regulate best with that load...give 2150fps.

These fastburning powders give significantly less recoil than the more slow burners..and the same velocity.

I'm not familiar with Vithavuori but RL15 seems popular for the .470.
Do you know what barrel length your buddys rifle had to produce that muzzle velocity?

 

[Pondoro]

24"

 

[Sideshow]

Just off AI

Kynoch historically published a relative burn rate chart for reference, but it does not publish the burn rate of the proprietary powder used in its current .470 Nitro Express factory ammunition.


If you’re trying to compare modern powders, the commonly accepted relative burn-rate order is approximately:

Faster​	Powder​	Slower​
IMR 3031	Vihtavuori N135	IMR 4064
IMR 4064	Vihtavuori N140	Alliant Reloder 15
Reloder 15	Hodgdon H4895	Vihtavuori N150
Vihtavuori N150	IMR 4320	Varget
Varget	IMR 4350	H4831

For the .470 NE, powders in the RL-15 / H4895 / N140 burn-rate range are generally considered the closest to producing the pressure curve needed to emulate traditional Kynoch ballistics in many double rifles. The exact proprietary Kynoch powder’s position on a burn-rate chart is not publicly available.


If your goal is to identify which commercial powder is closest to the modern Kynoch factory load, most experienced double-rifle reloaders would point to Alliant Reloder 15 as the nearest practical equivalent in terms of performance and regulation, although it is not the same powder.

A good way to visualize where the powders commonly used in the .470 NE sit is this simplified section of a modern relative burn-rate chart (fast → slow):

Relative position​	Powder​
Faster	IMR 3031
Hodgdon Benchmark
IMR 8208 XBR
H4895
IMR 4895
Vihtavuori N135
Norma 202
IMR 4064
Varget
Norma 203B
Alliant Reloder 15
Vihtavuori N140
IMR 4320
Slower	Reloder 16

For the .470 Nitro Express, the powders most often discussed are clustered very closely together:

• H4895 – slightly faster
• Reloder 15 – middle of the group
• Vihtavuori N140 – just a touch slower than RL-15
• Varget – just a little faster than RL-15 on many charts, although different charts may swap their order because burn rate is only a relative ranking.

It’s worth keeping in mind that burn-rate charts are guides, not substitution tables. Powders that appear adjacent can still differ significantly in energy, density, and pressure behavior, so neighboring powders are not interchangeable without pressure-tested load data.

“Me again hope that helps”

 

[uplander01]

Make sure you use filler for maximizing your powder column, start low and work your way up. The Garmin doppler can come in real handy,.....it will all come together when the velocity is somewhere between 2100 and 2150. When you get a few powders to that velocity one will be more accurate than the other, that's your load. H4250 falls right in the right burn rate as well and is the powder I've had best luck with in DR. The woodleigh manual is a great source of info.

 

[V.Veritas]

Thanks for sharing.
I've noticed there is a typo in the 1st table.
V N150 is listed as Faster and Slower.

 

[rookhawk]

After 9 months of waiting, my Charles Lancaster boxlock double has finally arrived in the country. The rifle comes with two barrel sets chambered in .470 NE and .375 H&H, both regulated for modern Kynoch ammunition.

As Kynamco has sadly gone into administration, I am left with the prospect of developing equivalent handloads for both.

Does anyone know what powder Kynamco used in their factory loads for these two cartridges? Or a close equivalent?

I have AR2209, 2213SC and RL-15, along with Woodleigh projectiles and Norma brass so between then I'm sure I can find something that will work, but if I can minimise shooting a 470NE off a bench for load development then all the better.

I believe they used RL15 in their loads. I've had no issues getting 470NE doubles regulated for Kynoch to regulate with IMR3031. The typical load for 3031 is 77gr of powder, 1.5gr of dacron stuffing, and a Federal or CCI magnum primer. The latter burns cooler so trying that first is best, if the bullets are a few inches apart changing to federal primers will bring them together due to faster and hotter ignition.

 

[rookhawk]

Faster​	Powder​	Slower​
IMR 3031	Vihtavuori N135	IMR 4064
IMR 4064	Vihtavuori N140	Alliant Reloder 15
Reloder 15	Hodgdon H4895	Vihtavuori N150
Vihtavuori N150	IMR 4320	Varget
Varget	IMR 4350	H4831

I like the chart very much for 470NE. The ones in bold I would avoid like the plague as their recoil is formidible.

RL15 and 3031 are the powders I prefer for vintage and modern 470s.

 

[rookhawk]

Make sure you use filler for maximizing your powder column, start low and work your way up. The Garmin doppler can come in real handy,.....it will all come together when the velocity is somewhere between 2100 and 2150. When you get a few powders to that velocity one will be more accurate than the other, that's your load. H4250 falls right in the right burn rate as well and is the powder I've had best luck with in DR. The woodleigh manual is a great source of info.

A 24"-25" double typically regulates at 2035fps to 2080fps. The published 2150fps was a myth perpetuated since the 1921/1926 ICI/Kynoch publshed data. (which was an embellishment, plus it was out of a 28" barrel)

 

[uplander01]

A 24"-25" double typically regulates at 2035fps to 2080fps. The published 2150fps was a myth perpetuated since the 1921/1926 ICI/Kynoch publshed data. (which was an embellishment, plus it was out of a 28" barrel)

I've only had 28" english double and it regulated at 2130 with H4350

 

[GerardV]

Okay thanks for the info gents. I'll start with the RL-15 and see how I go.

 

[rookhawk]

I've only had 28" english double and it regulated at 2130 with H4350

It's a valuable distinguishing characteristic. A general rule of thumb is 15fps to 30fps of velocity lost per inch of barrel less than 28".

For example, my Heyms at 2035fps with 24" barrels using 3031 would likely have been 2065fps with 26" barrels and 2095fps with 28" barrels.

I only point these things out for safety, not to be pedantic. A lot of people struggle to regulate their doubles and potentially get themselves seriously injured chasing 2150fps that was never reality. When newbies start developing loads with a chronograph they often start so fast they are already crossing, then they go with even more dangerous powders seeking more, more, more speed with good regulation. A fellow on this forum blew up a perfect condition ANCSL 470NE by shooting a full 2150fps 4831 load from it. (probably around 105gr or so...terrible idea)

 

[rookhawk]

Okay thanks for the info gents. I'll start with the RL-15 and see how I go.

Before you step up in half grain increments of powder with RL15, try a foam wad, then try 1.5gr of dacron stuffing. (the latter is higher pressure and alters regulation) In the same vain, try CCI magnum primer and if its too far apart, change only the primer to Federal 215.

You want reasonable pressure and a similar pressure curve to the original Kynoch ammo. These little tweaks can keep your pressure low before going the extreme step of another half grain of powder. Typically, with 3031 the regulation range is 75-77gr. I'd have to check my data for the RL15 load data but its a similar 3-4gr window between starting and ending.

My notes from Ross Seyfried via Ken Owen is that 470NE with a soft using RL15 has a max load of 89gr MAX. Starting load is probably around 85gr. (notes assume 1.5gr of loose dacron stuffing, lower pressure can be found with a wad)