Amazing 308 Win load data!

"I have a suspicion that factory barrels get higher velocity than the ultra-smooth custom tubes. Would be interested on your experience in this regard."

Ted, I once took some STP oil, the type meant to be added to engine oil and is the stickiest, hardest to get rid of, of any oil I have ever seen, out to the range with me.
I chronographed a load of five 30-06 cartridges. Then I took the identical cartridges and before I chambered each one, I coated all of the bullet that stuck out of the neck, with STP.
That group of five was 100 feet per second slower, than were the regular, uncoated bullets!
This falls in line with your super smooth barrel theory.
 
Why not? said:
To sum it all up, every rifle is a law unto itself. We all need to always be careful when handloading. Thanks for the heads up!

Hold hard, and breathe easy.

Ted
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I wish pressure trace equipment was more readily available. We know that pressure signs as indicated by bolt lift and primer appearance can be masked through very tight tolerances.

However, it doesn't change the fact that the steel was subjected to so many PSI's.

This was a common problem through most of the early years of wildcatting. No pressure gear. Amazing velocities were achieved with all manner of sharp shouldered wondercats.

the 7STW is one of the best documented examples of overpressure without pressure signs. With the hype that was generated, Rem stepped up and the cartridge was SAAMI certified. Velocities plummeted to not much more then a 7RM given the short barrels used in hunting applications. Sales reflected the lack of potency and this cartridge died quickly.

Same went for a cape buffalo smoking custom revolvers and chambering that seemed to defy the laws of physics with how much power and speed they could generate with nary a problem.

Lab test later confirmed that these handguns were touching 100,000psi with their wonder loads. A bit more and the steel could/would have grenaded. Very well designed revolvers though!!!

This chambering still exists today and is still VERY powerful. But it is no where near the performance pre lab tests.

New compact cartridges from Ruger and Hornady produce some very exciting performance from short barrels. They use a non cannister powder to achieve it. Wonder what results you would obtain handloading? Likely not very exciting.

Until someone, including the many shooters listed, can offer velocities AND pressure data showing some 'free lunch', I will keep a skeptical eye on the results.

Are there such things as high energy powders? You better believe it. Problem is that we can't access them nor their loading techniques (for the most part).

Re17 IS a new gen of powder that shares very exciting chemistry. This will be developed further and eventually apply to more and more powders. But when the powder manf releases load data that is not as exciting as some shooters are getting, I really wonder why.

Were you aware that for several years there has been a powder that will 'remove copper' as it burns? Good bye fouling....

Can we get this powder? Not yet and likely never as it would really cut into the sales of all that cleaning stuff...

YMMV....
Jerry

PS, just remembered a very knowlegeable loader and shooter was able to get OVER 3100fps out of a 308 and 155's. He even competed with this load at major matches without loss of life or limb. He has not pressure tested the load and has no intention of doing so. Do the math on that one.
 
Jerry - I assume you read the article on 6mmBR.com...if not it is quite interesting. You are right with the pressure, RL17 was loaded to 60,800psi vs 50,400psi with H4831SC in the 6XC to give 3211fps vs 2950fps with 115gr Bergers.

Do you think that RL17 will allow you to hold a peak preassure, or somewhere near it, for a longer time and thereby increase performance without extra peak pressure?
 
1899 said:
Jerry - I assume you read the article on 6mmBR.com...if not it is quite interesting. You are right with the pressure, RL17 was loaded to 60,800psi vs 50,400psi with H4831SC in the 6XC to give 3211fps vs 2950fps with 115gr Bergers.

Do you think that RL17 will allow you to hold a peak preassure, or somewhere near it, for a longer time and thereby increase performance without extra peak pressure?
Click to expand...

Amazes me that anyone would could make a comparison with such glaring problems. 60 vs 50K PSI is a monstrous difference in potential performance.

If you assumed that velocity and pressure are directly related (they most certainly are not but why worry about such details), the H4831SC load 'could' go 3500fps at 60K psi. In this world, I don't pay taxes, can eat all the cake I want and not gain any weight, date supermodels.....

This is why I don't get overly excited until there is data with properly normalized data. Run both powders at the same pressures (testing with real pressure test gear), in the same barrel and see what happens.

As much as I would love to say that Re17 gave me more velocity, it didn't. It behaved pretty much the same as other conventional powders.

To answer your question directly, you would need to compare pressure trace curves using proper test equipment and see what happens. I am sure there are some improvements but can't say for sure until some better data gets published.

Jerry
 
mysticplayer said:
Were you aware that for several years there has been a powder that will 'remove copper' as it burns? Good bye fouling....

Can we get this powder? Not yet and likely never as it would really cut into the sales of all that cleaning stuff...

YMMV....
Jerry
Click to expand...

Norma 204 has been compounded with tin ever since it's introduction. I have never seen metal fouling in any barrel using this powder. It will actually remove copper fouling from a barrel that was deposited there before starting to use this powder in it.

Ted
 
mysticplayer said:
Amazes me that anyone would could make a comparison with such glaring problems. 60 vs 50K PSI is a monstrous difference in potential performance.
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Of course it is! That is the whole point of the article. Develop a powder that can maintain higher pressure longer without spiking.

This is why I don't get overly excited until there is data with properly normalized data. Run both powders at the same pressures (testing with real pressure test gear), in the same barrel and see what happens.

As much as I would love to say that Re17 gave me more velocity, it didn't. It behaved pretty much the same as other conventional powders.
Click to expand...

Of course, you don't have any of this equipment, so your observations are just that, observations. The guys on 6BR used pressure trace
equipment.

I am sure there are some improvements but can't say for sure until some better data gets published.

Jerry
Click to expand...

Agreed. It will be good to see that!

Best,
Ted
 
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Andy, Jerry, Bruce, and others, I have been reading through this thread again this evening and seriously trying to sort through all of your information and comments.

Andy said:
Sounds reasonable - the part about smoothing out the pressure curve and adding more area (i.e. energy) under it. On reflection though, isn't that exactly what successively slower powders do? If you compare the pressure curve of Bullseye against RL25 you see this very clearly. Is the pressure curve for RL17 even flatter, but not as high?

There is no magic powder, just trying to understand what might be happening. Otherwise you have to conclude that the higher MV's are due to higher peak pressures.
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You know, Andy, I think that may be exactly what is happening. The pressure curve is flatter.

mysticplayer said:
If you look at the data published by Alliant, Re17 is not shown to offer any more speed at conventional pressures. however, in certain circumstances it most certainly does. Best news is that a new factory will be built in the US to cover more powder options using this tech. Eventually, we should see a whole range of powders delivering more fps/gr of powder burnt.

wonder what the effect on the barrel will be?
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That is encouraging, is it not Jerry, that there will be more development in this arena? Your question about barrel effects is certainly relevant. Higher and longer sustained pressure means higher and longer sustained heat as well, and further down the barrel. Will such powders erode the throat quicker and longer?

H4831 said:
I chronographed a load of five 30-06 cartridges. Then I took the identical cartridges and before I chambered each one, I coated all of the bullet that stuck out of the neck, with STP.
That group of five was 100 feet per second slower, than were the regular, uncoated bullets!
This falls in line with your super smooth barrel theory.
Click to expand...

Bruce, this is exactly what happens when moly is plated onto bullets.

There is a lot to think about, and discover in the days ahead. It will be interesting. :cool:

Ted
 
Why not? said:
Note that the IMR 4350 load in the Nosler manual, 50 gr, also gives the 180 gr 2700 fps in the 308, and is the most accurate load as indicated by the asterisk beside it.
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I run 180's at 2625 with 45.5gr Varget, from my 22" .308...

I think you'd have a very compressed load with 50gr of IMR 4350 in a .308 case, using a 180...
 
blargon said:
I run 180's at 2625 with 45.5gr Varget, from my 22" .308...

I think you'd have a very compressed load with 50gr of IMR 4350 in a .308 case, using a 180...
Click to expand...

It is compressed, and does get 2700 in two rifles I tried it in, however the 4064 load gets the same velocity, actually about 20 fps more, so stuck with that one.

Ted
 
Why Not?, my issue with using too grossly different max pressures is that IF the H4831SC load was raised to the same pressure as the Re17 load, I bet their muzzle velocities would be very similar.

It is like comparing the same car but with different motors and colour. Take a 4 cylinder Red car vs a V6 Blue car which goes faster and saying "blue cars are faster".

If they had the pressure trace gear, they should have equalized the peak pressures and then compared how the performance changed. Pretty sure they would have found little difference between the two powders.

H4831SC is one of the more docile powders and isn't peaky until well past what could be considered safe loading pressures. 60K psi is not hot at all. A typical magnum runs up to 65,000psi and truckloads of H4831 has been burnt in these over the decades.

Yes, the new chemistry is trying to increase the 'area under the curve'. Meaning if you looked at a pressure trace graph, the curve would raise to allowable peak pressures then stay there longer or have a shallower drop in pressure. This means the bullet is accelerated harder for longer which should lead to higher velocities.

Unfortunately, most barrels are quite short relative to the amount of energy available (why we have such a load muzzle blast) so most of that extra push never makes it to the bullet.

however, I remain excited about what new tech will be offered in the years to come. There will be fuels that will give more velocity per gr of powder burnt at the SAME peak pressure. But I feel that these same powders will put wear further down the barrel so setting back will be less useful.

There never is a free lunch.

I think the real gains will be in powders suitable for smaller cases with the prime one the 223/5.56 NATO

Jerry
 
mysticplayer said:
Why Not?, my issue with using too grossly different max pressures is that IF the H4831SC load was raised to the same pressure as the Re17 load, I bet their muzzle velocities would be very similar.
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You are missing the point, Jerry. You can't get enough 4831sc into the case to get the pressure to 60K. You can get enough Re17 in there.


mysticplayer said:
If they had the pressure trace gear, they should have equalized the peak pressures and then compared how the performance changed. Pretty sure they would have found little difference between the two powders.
Click to expand...

If you read the article, they are using pressure trace equipment.


mysticplayer said:
H4831SC is one of the more docile powders and isn't peaky until well past what could be considered safe loading pressures. 60K psi is not hot at all. A typical magnum runs up to 65,000psi and truckloads of H4831 has been burnt in these over the decades.
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Right, and running at the 60K level is what got these amazing velocities with Re17.


Just as an aside, I have personally burned up over a hundred pounds of the old surplus 4831. We used to buy it in 50 pound cardboard kegs for 50 cents a pound. Those were the days. :)



mysticplayer said:
Yes, the new chemistry is trying to increase the 'area under the curve'. Meaning if you looked at a pressure trace graph, the curve would raise to allowable peak pressures then stay there longer or have a shallower drop in pressure. This means the bullet is accelerated harder for longer which should lead to higher velocities.

Unfortunately, most barrels are quite short relative to the amount of energy available (why we have such a load muzzle blast) so most of that extra push never makes it to the bullet.

however, I remain excited about what new tech will be offered in the years to come. There will be fuels that will give more velocity per gr of powder burnt at the SAME peak pressure.

Jerry
Click to expand...

And, I will be one of the first to rejoice with you as that comes down the road.

Ted
 
Then they should have used a powder that could. H4350 would have fit in the case just fine and easily met their peak pressures. If not, then VARGET.

Why were they fixated on H4831SC in the first place?

Again, it is odd that you would set up an experiment where the outcome must be the answer you want. More infomercial then information.

Jerry
 
In the meantime, many of us will keep driving 150s at 3000, 180s at 2700, and 200s at 2500 in the 308 with various powders, and sharing that news with others, which was the original intent of this thread.

Please see the original post. :)

Ted
 
Ted, in one of your posts you stated, "PO Ackley told me one time---"
We sure would like to hear some more!
How about a story to complete the statement?
Bruce
 
Yep, quite the hijack. Oooops.

Back to the orig programming :)

Keep your eyes out for the next Re powder using this new chemistry. The rumor is it will useful in 223 with heavy bullets. If this happens, like Re15 on steroids, it will be HUGE for 308's too.

The goal is to make all those M4's behave like longer barreled rifles.

Jerry
 
Why not? said:
I don't remember you being called out about that, Rick. If I had seen that, I certainly would have supported you, as I have been using the 200 gr Speer in the 308 for more than twenty years.

Never got over 2600, but certainly close enough with Norma 204 that I would have come to your rescue. :D My latest venture being with a Stevens 200, factory 22" barrel, seated ten thou off the lands confirms what we already knew with our Husqvarnas. Just loaded some more today.

Care to give us some loads with N550 ? Starting loads would be a good place to begin. :)

Do you use moly with your loads?

Ted
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Starting load for N550 with 200 gr SMK is 43 gr, I have gone up to 46, but found 45.5 the sweetspot in my rifle with the 208 Amax.

Please note this is with Lapua brass and BR2 primers being fired in a tight match chamber start lower by at leat 10% and work up. YMMV

I do not subscribe to moly at all, Gun Juice is what I use in all my rifles.
 
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