Tried the New Hodgdon CFE powder

Originally Posted By: Orneryolfart357Hmm funny how different lists read? This one that I have used for quite a while actually shows 748 being a couple steps faster than H335.

http://www.reloadbench.com/burn.html

The final place is easy to determine for yourself - the weight of powder and the velocity it produces - look at a bunch of loading manuals and see where a powder falls on the weight/velocity relationship area - it is a pain, but you can lay it out on paper yourself.

Or you can go to one for the load software programs - 748 never produces more than 35 to 40Kpsia even with 105% loading density (and low velocity) in my 223 and 222 Mag cartridges.

I used to shoot it in benchrest many (MANY) years ago, in a 222 Mag - it was before we had access to pressure gauges. It shot very well, and so I campaigned it for several years. When I stopped shooting competitive bench, I restocked the rifle for crows, woodchucks, and PDs. Took it to SoDak one year with bunches of ammo to whack PDs.

Then it went into storage. A coupla years ago, I drug it out and put a Leupold 24x BR scope on it.

A local dealer/friend had a borescope so we looked at the throat to decide how far gone the barrel was, and he peeked in and said, "Have you shot this gun much?", and I asked why, and he said the throat looked new. Later I figured out the load on my software and the pressure of the load I was shooting was 32Kpsia. That's a little above the 22 rim fire, Ha!
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That number is consistent with the Hodgdon loading data - there are too many sources that confirm low pressure and low velocity with the combination of 222/223/222 Mag family of cartridges and 748, for there to be any doubt.




 
Why Powder Burn Rate Is Meaningless

By Randy Wakeman



Perhaps you have looked at various "Burn Rate Charts" and wondered what good they are. Well, you have good reason to wonder. Burn rate charts seldom agree. There is no specific meaning for "burn rate," so it shouldn't surprise us that the numbers don't agree. They mean nothing by themselves.

What amateurs call burn rate is not used by professional ballisticians to develop loads. The actual term closest to burn rate used in interior ballistics is "Relative Quickness."

Relative quickness is defined by "closed bomb tests," which quantify pressure rise in a sealed container. However, professional ballisticians do not use relative quickness for load development, either. A closed bomb relative quickness value does not translate into any type of value outside of that 'closed bomb' test. Powder performance varies widely by actual application. Relative quickness is one of several preliminary considerations when assessing a powder's suitability for a particular application by ballistics, but nothing more than that.

Relative quickness does not tell use the physical shape of a powder, its composition, or the types of coatings. It cannot tell us whether a powder is single-based, double based, or triple based. It does not tell us the heat of explosion, the progressive / degressive gas creation values, the ignition characteristics, and so forth. There is no way to translate a double-based powder performance into a single-based powder performance level with any accuracy. Even further, relative quickness does not define the erosiveness of a powder, the residue left by a powder, its ability to meter properly; and on it goes.

Energy content of nitrocellulose varies by manufacturer. It varies by the amount of nitrogen in the nitrocellulose. The more nitrogen, the more gas a powder can make. Once you have a specific type of nitrocellulose the energy content is further controlled by the addition of nitroglycerin, which is basically what constitutes a double-based powder. Now you have further considerations, as nitrocellulose and nitroglycerin do not behave the same way as temperature changes. The amount of nitro percentage varies by powder to powder, and with it its performance in a specific application.

All this combines to make burn rate charts something to ignore, or to view with very little importance placed on them. Professional ballisticians do not use them at all, simply because they have no particular meaning. Ping-Pong balls are nitrocellulose, but not many of us would bother cutting them up and attempting to use them in a firearm.
 
Now that's interesting. Different testing methods, maybe?

I'll relate my own personal experience with the combination: many years ago when I first began to reload .223, I had been using H335 and noticed that the max charge of H335 was just fine. I decided I wanted to try W748 because I had access to it in copious amounts. I rationalized that I should be able to go to the max charge of W748 since I was getting all my data from the same manual. IIRC, it was about 27.5 grains or so. At the range I set up my chronograph and began firing this ammo. I was getting velocity readings of about 3550 fps (!!!!!) with a Nosler 50-grain Ballistic Tip. I figured my chronograph was fritzing out, but after the second and third shots I realized I was shooting about a ten-inch group and that the bullet holes did not look right.

When I went down to look at my target I saw that the bullets were tumbling in flight, and I realized that those crazy velocities were probably for real.

The lesson that you really need to work up just like the manuals say was driven home with the utmost clarity, and that assumptions are dangerous.

I'm still not sure why those bullets were tumbling...maybe the excessive pressure deformed the bases or something, or maybe exit pressure upset the bullets...beats me.

If I can get enough W748 into a .223 case to generate excessive pressure and crazy velocity with a 50-grain bullet, it stands to reason that W748 is not too slow for the cartridge. It also stands to reason that it would work fine for a 55-grain bullet also.

I do think I'd start at around 24.5 grains and work up, though, if I were to play with W748 with .223 in the future.

Your thoughts?
 
Doesn't match what I get, and it doesn't match the known loading data.

But it is not worth more time, cuz it has reached the lever of how many angles can sit on a pin.
 
I wonder if there's a difference in the powder databases. My version of QL is 3.6.

Interestingly enough, my old Lyman 46th shows H335 with a 50-grain Sierra Blitz up to 30.0 grains of W748, with 3272 fps @37,100 CUP (this might have been enough to cause my little M70 to take its leave!). An old Winchester data pamphlet suggests 26.0 grains of W748 yielding 3160 fps @38,000 CUP.

There seems to be disparity everywhere.
 
Originally Posted By: RiverRiderI wonder if there's a difference in the powder databases. My version of QL is 3.6.

Interestingly enough, my old Lyman 46th shows H335 with a 50-grain Sierra Blitz up to 30.0 grains of W748, with 3272 fps @37,100 CUP (this might have been enough to cause my little M70 to take its leave!). An old Winchester data pamphlet suggests 26.0 grains of W748 yielding 3160 fps @38,000 CUP.

There seems to be disparity everywhere.

I think part of it is that it is really difficult to measure pressure accurately.

I have worked in the ammunition business for longer than I will admit (though my 20yo Rug Rat says I'm 917 years old
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)

I have a pressure gun boxed up in the basement, and some years ago, I ran tests on a bunch of ammo and none of it was "on the mark".

Which did not surprise me, cuz SAAMI took some calibrated pressure cartridges and sent a bunch to every outfit in the country that had a certified pressure gun, and asked them to report back what the pressures were - and the answers they got were all over the place.

And there is a reason for that - the people in the industry use pressure guns to meet "Their" standards - it doesn't make much difference what the actual "true" pressure is, because it varies from test barrel to test barrel, and also varies with the hysteresis of the plug or strain gauge - as long as "they" can repeat it from batch to batch (lot to lot), that's all that matters.

To the amateur/hobby loader, when they read that such an such a load develops 56,700psia, they actually believe that figure - in the industry, it is just a reference figure... as long as each batch says 56,700, then there is uniformity, so "... keep on keeping on" - that ammo measured by the company down the road might measure 51,500, or 59,500 - Quen Sabe - who cares??
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And that same load in "their rifle" will be no where close to 56.7Kpsia

Pressures have been climbing over the years - the original pressure standards for the 222 family of cartridges was ~45Kpsia - now, you can't find a factory 222 family cartridge that runs in the mid 40k's... they are all running 10 to 15 Kpsia higher.

It is a fascinating field, if you can be loose and understand the bigger picture.

My friends say I love making ammo more than shooting it
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That's almost, but not quite - true.

Meow
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I certainly agree that it is a fascinating subject. I've seen, read, and heard so many different ideas and theories that cannot possibly all be true (or could they?) yet it's nearly impossible to decide what to discount.

Cheers.
 
Originally Posted By: RiverRiderI certainly agree that it is a fascinating subject. I've seen, read, and heard so many different ideas and theories that cannot possibly all be true (or could they?) yet it's nearly impossible to decide what to discount.

Cheers.


It takes YEARS of wading through the numbers and processes (sometimes with your hip boots on
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) until you start seeing a larger picture.

The web is not a good place to learn it in the beginning, because there is so much BS and you can't tell the real players from the 16 year olds that want to argue about everything. Later on, after you have some foundation, it is easy to avoid the children and the garbage.

I love it, and I'm lucky enough to live a few miles from SAAMI's libraries.
 
There's a good write up on this powder in Guns & Ammo April (2012), sounds to me like it does what it say's it will do....you be the judge!

Steve
 
Originally Posted By: Steve K.There's a good write up on this powder in Guns & Ammo April (2012), sounds to me like it does what it say's it will do....you be the judge!

Steve

Have you ever read a gun magazine article that was critical of a product they were writing up???

A gun magazine (especially Guns & Ammo) is the last place you should get information about, ".... sounds to me like it does what it say's it will do."

They get paid to write nice things about the advertisers products.

If the writer says the product doesn't work well, the advertize drops their advertizing, the magazine looses money, and the writer doesn't get any more articles published... that's how the gun magazine world works.
 
Originally Posted By: Steve K.Read the article and check out the bore scope pictures!

Steve

I just read that article today Steve. I agree looks good to me, unless they`re blowing some major smoke up..
 
I have been reloading for 40+ years and have always considered data by the various bullet and powder manufacturers to be guide line information. CatShooter is a pro and he's right, there is no way it is exact in data from one source vs another.

If you own a few manuals, you have noticed the odd changes from bullet maker to maker...those [beeep] things (bullets) are all different too
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Hodgdon's latest lists IMR 4320(#100), W748(#101), BLc2(#102) and CFE(#103). It's pretty clear it is a re-do of one of these with some new jargon. It gives me about the same level of performance as the above powders. I plan to run all four across a crony with all components matching and charges as close to the same as possible. So far, BLc2 seems closest, With CFE about as dirty in the bore.

I will say that 10 shot groups (another shooter/loader) in .308 and 175 gr. match are averaging 3/4 MOA at 100 yds. More test to come when the weather permits. Horribly windy of late here but nothing like Indiana and Kentucky. Prayers for all those folks.
 
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