H414 and W760 powders: Are they one and the same?

[Brians356]

I was poring over Hodgdon's load data and stumbled on an oddity: In nearly every case, for many cartridge/bullet combinations, Hodgdon publishes identical data for both H414 and W760 powders. In particular, these duplicate data can be seen for cartridges like 243 Win, 6mm Rem, 243 WSSM, 257 Roberts, 6.5x55 Swedish, etc. When I say identical, I mean literally, as if cut/pasted.

Yet in Hodgdon's descriptions of these powders themselves, no mention is made about H414 and W760 even being similar, much less interchangeable or even identical.

From the data, however, I have to conclude these powders are in fact the same, and are manufactured by the same producer.

True?

Brian

 

[CatShooter]

Yes...

But you still have to work up loads if you switch.

 

[Catfur]

There are a number of powders out there that are the same (within the limits of lot-to-lot variation, which can be pretty big). Several of the Winchester/Hodgdon ball propellants, (760/H414 and I think it's 748/BLC(2) but don't quote me on that). Also, the new Alliant Power-Pro are made at the same place (St. Marks factory in FL) and are likely just repackaged versions of the same. Norma makes many of the Reloader series of powders, and some of their powders are likely equivalent to appropriate RL-series powder. It wouldn't surprise me if there are more out there.

 

[bheadboy]

I find them the same with the exception of lot so Catshooter is correct, work up loads

Bob

 

[Brians356]

Yes...

But you still have to work up loads if you switch.

Same caveat as if I had a twenty-year old batch of H414, and was now starting to use a brand new batch of H414. It's the lot-to-lot inconsistency factor. If I knew bottles of H414 and W760 were from the same lot, and had been stored together (not subjected to different conditions) there would be no reason to. The problem is how can one ever know for sure?

Odd though, ain't it, that Hodgdon chooses not to mention they are the same powder?

What other powders in the Hodgdon stable of brands (Hodgdon, IMR, Winchester) are actually identical?

Brian

 

[swehrman]

HP-38 and WW231 are the same.

-- Scott

 

[Brians356]

The reason I was looking closely at load data was I was comparing 6mm Rem data with 243 WSSM (the latter has CFE 223 powder data published, the former none yet.) I'm starting a new thread about the startling similar interior ballistics between these two cartridges.

Brian

 

[3Ackleys]

In pistol powder H110 and w296 are the same too

 

[CatShooter]

The reason I was looking closely at load data was I was comparing 6mm Rem data with 243 WSSM (the latter has CFE 223 powder data published, the former none yet.) I'm starting a new thread about the startling similar interior ballistics between these two cartridges.

Brian

The 6mm Rem is about 8% larger, and if loaded to the same pressure, will give higher velocities and energy.

In reverse, if you are going to use 6mm Rem data to load the 243 WSSM, drop 20% and work up... not 10% as usual.

 

[Brians356]

The 6mm Rem is about 8% larger, and if loaded to the same pressure, will give higher velocities and energy.

In reverse, if you are going to use 6mm Rem data to load the 243 WSSM, drop 20% and work up... not 10% as usual.

I believe 6mm Rem has only ~4% more case capacity than 243 WSSM.

But in any case, the Hodgdon data disputes what you are saying - that equal pressures would shove 6mm significantly out front.

Let's look at one powder, Superformance, common to both cartridge datasets for the 70-grain bullet I cited:

Max charge / velocity / pressure for Superformance, 70-grain bullet:

6mm Rem: 54.0 gr / 3812 fps / 61,000 psi
243 WSSM: 54.0 gr / 3812 fps / 61,000 psi

No, you're not seeing double! Those values are straight out of Hodgdon's data. And pressures are equal.

How about another common powder? IMR 4007 SSC, yielded these results:

6mm Rem: 48.0 gr / 3632 fps / 58,900 psi
243 WSSM: 48.0 gr / 3616 fps / 59,800 psi

Again, charges and velocities are identical, yet 243 WSSM was loaded to only a 1.5% higher pressure than 6mm Rem. Suppose 6mm Rem was loaded to 1.5% higher pressure? We might expect 50-60 more fps, and 6mm Rem might be only about 2% faster. These small differences of < 2% are all in the measurement error noise.

I could rest my case here, but to be fair, let's look a third common powder, Varget, which does not show identical max charges:

6mm Rem: 44.5 gr / 3639 fps / 59,500 psi
243 WSSM: 43.7 gr / 3655 fps / 63,400 psi

The 6mm was loaded with 1.8% more powder, but velocity for 6mm Rem is 0.44% lower. Yes, the 6mm Rem maxed out at a lower pressure (presumably from adverse pressure signs.) But if it was loaded somewhat hotter, it would surpass but probably not exceed the WSSM velocity by more than a percent or two.

So I still contend these two cartridges are virtually identical WRT interior ballistics, when measurement errors are considered. I defy anyone to find any two standard cartridges which have such nearly identical load data than these two - or even close.

Brian

 

[3Ackleys]

The 6mm Rem is about 8% larger, and if loaded to the same pressure, will give higher velocities and energy.

In reverse, if you are going to use 6mm Rem data to load the 243 WSSM, drop 20% and work up... not 10% as usual.

I believe 6mm Rem has only ~4% more case capacity than 243 WSSM.

But in any case, the Hodgdon data disputes what you are saying - that equal pressures would shove 6mm significantly out front.

Let's look at one powder, Superformance, common to both cartridge datasets for the 70-grain bullet I cited:

Max charge / velocity / pressure for Superformance, 70-grain bullet:

6mm Rem: 54.0 gr / 3812 fps / 61,000 psi
243 WSSM: 54.0 gr / 3812 fps / 61,000 psi

No, you're not seeing double! Those values are straight out of Hodgdon's data. And pressures are equal.

How about another common powder? IMR 4007 SSC, yielded these results:

6mm Rem: 48.0 gr / 3632 fps / 58,900 psi
243 WSSM: 48.0 gr / 3616 fps / 59,800 psi

Again, charges and velocities are identical, yet 243 WSSM was loaded to only a 1.5% higher pressure than 6mm Rem. Suppose 6mm Rem was loaded to 1.5% higher pressure? We might expect 50-60 more fps, and 6mm Rem might be only about 2% faster. These small differences of < 2% are all in the measurement error noise.

I could rest my case here, but to be fair, let's look a third common powder, Varget, which does not show identical max charges:

6mm Rem: 44.5 gr / 3639 fps / 59,500 psi
243 WSSM: 43.7 gr / 3655 fps / 63,400 psi

The 6mm was loaded with 1.8% more powder, but velocity for 6mm Rem is 0.44% lower. Yes, the 6mm Rem maxed out at a lower pressure (presumably from adverse pressure signs.) But if it was loaded somewhat hotter, it would surpass but probably not exceed the WSSM velocity by more than a percent or two.

So I still contend these two cartridges are virtually identical WRT interior ballistics, when measurement errors are considered. I defy anyone to find any two standard cartridges which have such nearly identical load data than these two - or even close.

Brian
the 7mm express and the 280 Remington are pretty close ;D

 

[Brians356]

Brian
the 7mm express and the 280 Remington are pretty close ;D

Yes, they are. You got me there, mate. I stand rebuked. So are the 244 Rem and 6mm Rem. And the 250 Savage and 250-3000 are pretty close, too.