Does anyone know if there is a near-equivalent to cordite among the modern powders? I was wanting to duplicate original loads for some old build-for-cordite cartridges (303B, 300 H&H, 375 H&H).
Thanks,
tq
No arsenal, or no weapon in the arsenals of the world, is so formidable as the will and moral courage of free men and women. - Ronald Reagan
Over at Accurate reloading..Some of the really experienced double gun shooters(Ray Atkinson and others) have said the equivalent was RL-15( on a % basis)..BUT either go by the professional advice one of the writers gives you or go over there to get confirmation..
Reloder 15 is indeed often suggested as the starting powder for loading double rifles, since the ammo for many was originally loaded with a powder that had a similar pressure curve. The theory is thet you match the pressure curve and your rifle should "regulate."
This sodesn't always work, though. If it doesn't one solution is to use a much slower burning powder. I've seen rifles that failed to regulate with R15 do fine with H4350 or H4831. (All three of these powders are preferable to most others because they tend to produce the same velocities anywhere from 80 above down to zero F. Many doubel rifles go out of regulation in cold temperatures with loads developed at "normal" temps.)
All of this of course has nothing to do with working up loads for the cartridges mentioned--unless they're used in a double rifle. You can duplicate original Cordite velocities with about any modern powder from IMR4895 to H4350 as long as it fills the case sufficiently to burn evenly. By the way, the .303 was not originally designed for Cordite, but black powder.
“Montana seems to me to be what a small boy would think Texas is like from hearing Texans.” John Steinbeck
I understand that for a number of years IMR 3031 was used as a rough substitute for cordite.
More recently, the writings of Ross Seyfried have suggested that taking a given charge of cordite, multiplying that amount by 1.19 and using the resultant number as a charge of Reloder 15 yields close to identical pressures and velocities in a wide number of cartridges, from the .303 British through the big elephant boomers.
I've never reloaded for any cordite cartridge and have no personal knowledge of whether this substitution works, but Mr. Seyfried has written about his successes with this formula for a number of years. You might want to read some of his articles in back issues of "Rifle" and "Handloader" and decide for yourself.
Have you ever fired or seen fired any cordite loads?
A pretty well known gunsmith, Hook Boutin, once mentioned that during WWII he had often wished for one of the Brits .303's because they didn't give off the cloud of smoke in the cold mornings like his Garand did...I thought it was as smokey or smokier than modern(for that time) powders....
At the suggestion of ROTR I searched on accuratereloading for cordite and found the same question had been asked and answered over there:
**********Quote*************** John Frazer One Of Us Member # 5724
posted 01-10-2002 22:20 -------------------------------------------------------------------------------- Ross Seyfried says the list of substitutes "begins and ends with RL-15" or words to that effect. He uses some kind of poly filler to make up the volume difference -- this was in a recent "Handloader" article. John
-------------------------------------------------------------------------------- Posts: 941 | From: Northern Virginia, USA | Registered: Jun 2001 | IP: Logged
John S Forum Leader Member # 8265
posted 01-10-2002 22:50 -------------------------------------------------------------------------------- I totally agree with Seyfried on this. Having tried 3031 and 4831 I find the R15 allows much easier regulation with proper velocity. Use his ratio of 1gr Cordite to 1.19grs of R15. *********End Quote*****************
Thanks!
No arsenal, or no weapon in the arsenals of the world, is so formidable as the will and moral courage of free men and women. - Ronald Reagan
I don't know squat about double rifles (except that they look purdy). For years I have been preaching that, in 303s, 43.0 gr. of Re15 with 174/180 grain bullets is the ticket. I don't know whether that fits with that formula, but it doesn't matter. He must have been at my website. <img src="/ubbthreads/images/graemlins/grin.gif" alt="" />
Varget delivers tighties as well.
Safe Shooting! <img src="/ubbthreads/images/graemlins/grin.gif" alt="" /> Steve Redgwell 303british.com
I know Ross very well and we have discussed this some over the years, and I've read every article he's ever written for Rifle and Handloader. The formula works reasonably well, depending on the lot of R15, and is handy for somebody shooting an old British rifle with essentially fixed sights.
But it doesn't always work in doubles, or older single-barrel rifles made somewhere else than Britain, because many if not most other countries didn't use Cordite. Germany was using some sort of flake powder at the same time. And there's no reason to stick to R15 with the .300 or .375 H&H in a scoped bolt rifle (or the .303 for that matter), because you're not trying to get the rifle to "shoot to the sights."
Whether you use it in a .303 depends on many factors. If you happen to have a .303 with iron sights regulated for cordite, then of course the R15 formula is a place to start. If your .303 is scoped, or a later model regulated with newer powders, it may not work so well--though of course R15 is a great powder for almost any medium-capacity cartridge.
“Montana seems to me to be what a small boy would think Texas is like from hearing Texans.” John Steinbeck
My last response was intended to answer the question asked by the original poster. After re-reading my comments above, however, it seemed to me that my words might be construed to suggest that YOU should read the writings of Ross Seyfried. Obviously, I would not mean that since he is your colleague.
I, too, enjoy the writings of Mr. Seyfried. I've never shot (or even seen) most of the classic and exotic rifles he writes about, but his enthusiasm is definitely infectious. He writes about great, really great rifles and experiments and I'd direct anyone with questions in Mr. Seyfried's area of expertise to consult his writings.
As I said above, I hope my earlier post didn't come across like it was addressed to you. If it did, then it would seem to contain an air of arrogance and superiority that I DEFINITELY did not intend!
I know Mule Deer is old <img src="/ubbthreads/images/graemlins/grin.gif" alt="" />, but I don't think he was around in cordites heyday.. <img src="/ubbthreads/images/graemlins/shocked.gif" alt="" />
Sorry, though they were directed to me because you clicked to respond on my message.
Ready--Yeah, I'm an incipient geezer, but not quite old enough to have fooled around with cordite. I have no idea why American powders would "smoke" on cold mornings and not cordite. Anybody else?
“Montana seems to me to be what a small boy would think Texas is like from hearing Texans.” John Steinbeck
I'm just thinking out loud here: mabye it was not "smoke", but steam. Is there water vapor in rifle exhaust? Perhaps the US powder gave off more than others, and the cold mornings made for a dew point that caused the water vapor to be more visable?? Just a WAG.
WRT cordite (smokeless) regulated sights, that would be virtually any rifle made after 1910 - including retrofits to upgrade older rifles.
I have done a bunch of work (published and otherwse) on this and other subjects for the 303. 43.0 grains will give you Mk VII velocities which is what most rifles are made to shoot. The sights being changed to coincide with the adoption of the Mk VII round in 1910.
The top three performers in this cal are Re 15, Varget and N140 with 174/180 grain bullets. Absolutely no question about this, based on input from around the world.
The steam theory is interesting. When cordite was first used, there were very few smokeless powders available. Pressures and temperatures with this "new" powder were significantly higher than black powder. Cordite was known to burn very intensely. Perhaps hotter than other existing smokeless powders??? The old practice of stacking rifles outside one's tent would allow moisture to collect on the inside of the barrel. You would think that it wouldn't matter, given that water turns to steam at approx. 212 F or 100 C.
I don't know what the heat generation was for cordite, but single base powders (like IMR 4895) burn with less heat than double base powders.
Safe Shooting! <img src="/ubbthreads/images/graemlins/grin.gif" alt="" /> Steve Redgwell 303british.com
I may have to ride up and harrass hook about it and see if he can go into further detail..last time I was to busy watching the 70+ yr old bang away at the gong with the Garand <img src="/ubbthreads/images/graemlins/grin.gif" alt="" />
It's been awhile, heck he may have said less flash..whatever it was kept the Germans attention on the Americans and he didn't like it!!
Steve, I have a couple of questions for you regarding cordite in .303 cartridges.
Please correct me if I'm wrong.
I understand that the standard cordite charge with the 215-grain bullet was in the range of around 31 grains. Ross Seyfried once wrote that multiplying this number by 1.19 gave him about 36.9, rounding off to 37 grains. When he used this charge of Reloder 15 in an 1880's vintage Lee-Speed (that had actually been rifled by Sir William H. Metford, personally, I believe), he found the velocity and regulation perfect when using the Woodleigh 215-grain. Have you ever tried a similar experiment with a 215?
Secondly, I understand that the WWI cordite load was in the range of about 37 grains with the standard 174-grain military F.M.J. Due to heat erosion in machinegun barrels caused by cordite, the Brits actually contracted with DuPont to produce a band-new, single-base powder called MR16 which allegedly burned much cooler. This powder was then used in the Mk.8z rounds. I understand that the charge of this new powder was nearly identical to the former charge of cordite, for similar performance -- around 37 grains and the standard 2,400 feet-per-second.
I also understand that after the war this "MR16" powder was marketed to civilians and slightly improved. DuPont named it "IMR 3031". To this day, 37 grains of IMR 3031 and a 174-grain bullet remains a classic .303 load.
Am I correct in this understanding? I seem to recall some discussion of the history of .303 loads on your website.
If this story is true, then IMR 3031 might well be a pretty good subsitute for cordite.
By the way, I've never had great luck with Varget in the .303 (although it remains my powder of choice for Palma loads in the .308). Instead, I've found IMR 4320 to be simply excellent in this old British warhorse.
I've no experience with Re15 in a double rifle. Lots of time with LEs, Enfields etc.
I've shot many, many rds of Re15 and 215 gr Woodleighs from No4s and P-14s. It's a mild load which doesn't broach 40,000PSI and closely matches the MkVI load of 2050 fps. My avg from accumulated data - 2072fps. They just wouldn't group worth a darn from any of my rifles. 4320 and H414 performed the best in almost all of the rifles used. None of them were regulated for 215s however.
The rifles used all had Enfield rifling, which is deeper and more angularly ridged. Seyfried's results would be different with the Metford type.
It's interesting to note that around 1900 the cordite recipe changed because of the erosion problems with the then "new" Enfield rifling. The original composition was NC-37%, NG- 58%. NG causing most of the heat/erosion effect. It was basically flip flopped to NC-65%, NG30% to "cool" the burn and slow the erosion. I wonder if the 1.19 multiplier worked for both mixes?
I have a reference to MR16, but nothing that directly ties it to, or being the same as IMR3031. I had heard that too. I just don't have any concrete proof. We did bounce it around on the site, but no one could provide any documentation. Heck, we should have just asked IMR and hoped that they had records.
Personally, 37.0 of IMR3031 and a 215 gr bullet is a max load - 2160 fps. and around 46,000PSI. 37.0 gr loads built for the 180 gr. Sierra spitzer were midrange. Avg 2139 fps. Pressures were a bit less than 40,000PSI also.
Safe Shooting! <img src="/ubbthreads/images/graemlins/grin.gif" alt="" /> Steve Redgwell 303british.com
These are starting points. A lot of discussion pro and con on wadding to fill up case. Some people maintain it can ring the chamber. Those liking 4831 also get full cases of powder/ no wadding.
Seyfried seems to be more familiar with Nitro for Black and Black than Cordite. Just my opinion but I have read many things that I and a lot of others disagree about.
3031 and 4350 can be dangerous and should be avoided.
Mickey
"Instead of getting married again I am just going to find a women I don't like and give her a house"
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