Sources for Pressure Data?
- Thread starter fritz1255
- Start date
Hodgdon's online load manual http://data.hodgdon.com/main_menu.asp
and Ramshot online manual http://www.ramshot.com/wp-content/uploads/2010/09/ramshot_handgun_rifle.pdf
Both have pressure for most loads.
Good luck, and good shooting!
and Ramshot online manual http://www.ramshot.com/wp-content/uploads/2010/09/ramshot_handgun_rifle.pdf
Both have pressure for most loads.
Good luck, and good shooting!
I tried Quickload, it does give you a starting point, but you still have to work the load up for safety in your rifle. So why pay $150 for a starting point when you can get a starting point for free from a manual. Quickload is within 5% for .308 Win, but when you start to depart from cartridges it does well Quickload struggles. I have a pressure test setup, that's the only real way to know what it really going on inside your chamber!
Quickload was about 10% off my real results in 260 Rem and 6.5-284, to me that's not acceptable, and tweaking the model parameters to match the results is invalid experimental technique.
If it works for you great, IMHO save the $150 and wait till you can get a pressure trace system.
Good luck, and good shooting
Quickload was about 10% off my real results in 260 Rem and 6.5-284, to me that's not acceptable, and tweaking the model parameters to match the results is invalid experimental technique.
If it works for you great, IMHO save the $150 and wait till you can get a pressure trace system.
Good luck, and good shooting
Hi Ftritz
Hi there,I'm no expert,far from it,but since you seem to look for manuals with reliable datas concerning pressure,why don't you check Richard Lee's manual(2nd edition),certainly compiling results from Hodgdon,IMR,Winchester what not,there's also a whole technical section dedicated to pressure in it,and besides all that,it's a good read,makes you feel like your old uncle is kindly letting you on into some secrets of his, worked for me...
Hi there,I'm no expert,far from it,but since you seem to look for manuals with reliable datas concerning pressure,why don't you check Richard Lee's manual(2nd edition),certainly compiling results from Hodgdon,IMR,Winchester what not,there's also a whole technical section dedicated to pressure in it,and besides all that,it's a good read,makes you feel like your old uncle is kindly letting you on into some secrets of his, worked for me...
There are good pressure trace systems are out there, just search around. I'm not going to plug anybody's product, but I'm sure you can find some.
If you still can't find any PM me and I will tell you what type I use.
Good luck, and good shooting.
If you still can't find any PM me and I will tell you what type I use.
Good luck, and good shooting.
Listen to itchy he's a sharp one.
Oehler 43 is out of production last I looked, and cost upwards of $1500, I did like their acoustic target option, but not $1500 worth, but its all moot since we cant get one anyway. I did prices Oehler commercial chronograph, pressure system and you are looking at $10,000 ball park if my memory is correct. Way too much for me.
Good luck!
Oehler 43 is out of production last I looked, and cost upwards of $1500, I did like their acoustic target option, but not $1500 worth, but its all moot since we cant get one anyway. I did prices Oehler commercial chronograph, pressure system and you are looking at $10,000 ball park if my memory is correct. Way too much for me.
Good luck!
What good would knowing the pressure do?
How accurate is a pressure trace system?
Double fallacy.
The brass is the weak link, and the load must be a safety margin away from short brass life.
Quickload is far better than any load book or pressure trace system to get to the optimum load the quickest.
How accurate is a pressure trace system?
Double fallacy.
The brass is the weak link, and the load must be a safety margin away from short brass life.
Quickload is far better than any load book or pressure trace system to get to the optimum load the quickest.
How will a theoretical model ever be better than real world measurement? The presser measuring system is good to within a few hundred PSI. You have to have a calibration load to start out. Once you get a base line from factory ammunition, or a load from a manual that give pressure, you can see where your pressure levels are to a high level of precision.
Not only can you see peak pressure, you can see area under the curve and how that relates to muzzle velocity. Then you can really see what powder is working the best in your rifle, and why some powders don't work. If peak pressure is reached to soon you will always see lower muzzle velocity.
I have more than 50 traces for my 260 Rem rifle, I can tell you in one shot if a powder is to fast or two slow and how much more powder you can use safely. Once you have good base lines a pressure system will save you hours and many $$$.
True, brass is the weak link, but with out a pressure measuring system you have know way to know how weak it is. Very hard brass can take pressures that will eventually damage you rifle with out showing pressure signs. Some brass and some rifles will show pressure signs before you reach good working pressure. My Rem 700 in 308 Win is a prime example, due to a large firing pin hole it craters every primer, factory load, heavy load, light load, all give what looks like a pressure sign on the fired case. So with quickload what would you do, keep going up till you pop a primer out? No thanks, I prefer to have real data on exactly what is happening in my chamber.
If you want to pay for Quickload be my guest, but as a reloader with over 15 years experience and a professional laboratory scientist Quickload does not offer any data I would trust to avoid the cost and time of full load work up, and you can do that starting with the free data from major manuals. The only use I can see is to get a better starting point with powders that are not in manuals you have access to, but even in that case, if you have any idea what the burn rate is just do a 1g ladder and you will find out.
If Quickload cost $20 it would be worth it, but at $150, its just not! If you really want to learn what is the best load in your rifle and what powder to use get a pressure system, it's the only way to go if you are serious about your shooting.
Not only can you see peak pressure, you can see area under the curve and how that relates to muzzle velocity. Then you can really see what powder is working the best in your rifle, and why some powders don't work. If peak pressure is reached to soon you will always see lower muzzle velocity.
I have more than 50 traces for my 260 Rem rifle, I can tell you in one shot if a powder is to fast or two slow and how much more powder you can use safely. Once you have good base lines a pressure system will save you hours and many $$$.
True, brass is the weak link, but with out a pressure measuring system you have know way to know how weak it is. Very hard brass can take pressures that will eventually damage you rifle with out showing pressure signs. Some brass and some rifles will show pressure signs before you reach good working pressure. My Rem 700 in 308 Win is a prime example, due to a large firing pin hole it craters every primer, factory load, heavy load, light load, all give what looks like a pressure sign on the fired case. So with quickload what would you do, keep going up till you pop a primer out? No thanks, I prefer to have real data on exactly what is happening in my chamber.
If you want to pay for Quickload be my guest, but as a reloader with over 15 years experience and a professional laboratory scientist Quickload does not offer any data I would trust to avoid the cost and time of full load work up, and you can do that starting with the free data from major manuals. The only use I can see is to get a better starting point with powders that are not in manuals you have access to, but even in that case, if you have any idea what the burn rate is just do a 1g ladder and you will find out.
If Quickload cost $20 it would be worth it, but at $150, its just not! If you really want to learn what is the best load in your rifle and what powder to use get a pressure system, it's the only way to go if you are serious about your shooting.
I know the 43 is out of production but every now & then they pop up for sale. If Oehler doesn't supply the strain gauges anymore that might be a problem unless you can use brand x's.Oehler used a 1NA128 amplifier.
You can do a lot better for amplifiers.
You can buy CEA-O6-250UW-350 strain gauge.
But you don't know what you are doing if you want to measure pressure for your own gun with a strain gauge.
Seriously.
Do you use a hydrometer to measure if the girl wants to marry you?
No, you look and listen to the girl.
Just like you don't use a strain gauge to measure if your pressure exceeds the threshold of long brass life.
You look at the brass.
Just sit down and ask yourself 100 times, "What am I trying to accomplish?"
Unless you have an iron in the fire like Denton Bramwell, the answer is, "I want to find the threshold of long brass life, by looking at my brass. I have been so stupid fooling with a strain gauge. Please don't tell anyone that I put a strain gauge on my rifle. Do you want to buy a copy of Roark's book? I used it and a calculator, and all my measurement were meaningless. I am so ashamed I fell for that."
http://www.amazon.com/Roarks-Formulas-Stress-Strain-Warren/dp/007072542X
You can do a lot better for amplifiers.
You can buy CEA-O6-250UW-350 strain gauge.
But you don't know what you are doing if you want to measure pressure for your own gun with a strain gauge.
Seriously.
Do you use a hydrometer to measure if the girl wants to marry you?
No, you look and listen to the girl.
Just like you don't use a strain gauge to measure if your pressure exceeds the threshold of long brass life.
You look at the brass.
Just sit down and ask yourself 100 times, "What am I trying to accomplish?"
Unless you have an iron in the fire like Denton Bramwell, the answer is, "I want to find the threshold of long brass life, by looking at my brass. I have been so stupid fooling with a strain gauge. Please don't tell anyone that I put a strain gauge on my rifle. Do you want to buy a copy of Roark's book? I used it and a calculator, and all my measurement were meaningless. I am so ashamed I fell for that."
http://www.amazon.com/Roarks-Formulas-Stress-Strain-Warren/dp/007072542X
itchyTF
Gold $$ Contributor
Curious, from Denton Bramwell himself -
"We all know the pressure signs: flattened primers, sticky bolt lift, split cases, etc. But
once you start seeing these signs, how much should you back down? Some authors hold
that by the time you’re seeing classical pressure signs, you can be a long way over the
limit. And wouldn’t it be better to know before you’re over the limit, instead of after? If
you want your gun to last a long time, it’s a lot better. Fortunately, you can now do your
own pressure measurements, without disfiguring your rifle, for a very reasonable cost.
As I’ve discussed in a previous article, there are three common methods for measuring
barrel pressure. Both the CUP method and the piezoelectric method involve drilling a
hole in the test barrel chamber. The strain gauge method only requires that you glue a
strain gauge to the outside of your chamber. Since the gauge is about the thickness of
piece of paper, and about ¼†x ½â€, it is easily concealed under the stock. Strain gauges
are undoubtedly the best of the three for the home reloader."
.
.
.
"My conclusion is that the strain gauge system gives you excellent repeatability, and the
absolute accuracy is probably decent. But nobody can tell you how decent."
"We all know the pressure signs: flattened primers, sticky bolt lift, split cases, etc. But
once you start seeing these signs, how much should you back down? Some authors hold
that by the time you’re seeing classical pressure signs, you can be a long way over the
limit. And wouldn’t it be better to know before you’re over the limit, instead of after? If
you want your gun to last a long time, it’s a lot better. Fortunately, you can now do your
own pressure measurements, without disfiguring your rifle, for a very reasonable cost.
As I’ve discussed in a previous article, there are three common methods for measuring
barrel pressure. Both the CUP method and the piezoelectric method involve drilling a
hole in the test barrel chamber. The strain gauge method only requires that you glue a
strain gauge to the outside of your chamber. Since the gauge is about the thickness of
piece of paper, and about ¼†x ½â€, it is easily concealed under the stock. Strain gauges
are undoubtedly the best of the three for the home reloader."
.
.
.
"My conclusion is that the strain gauge system gives you excellent repeatability, and the
absolute accuracy is probably decent. But nobody can tell you how decent."
Denton Bramwell has been on the internet spreading this stuff more more than 10 years.
The two basic errors:
1) Measuring absolute pressure is useful to the handloader.
2) Absolute pressure can be measured with a strain gauge, given the geometry of an open ended tube with a taper on the outside and a taper on the inside and a strain gauge bonding placement with out of control orientation and location.
Understanding the first error:
Registered pressures are based on the limits of the brass in strong rifles. In the first three case head designs, the primer pocket will get loose at high pressure. The goal of the work up is to find the threshold of long brass life and then back off a safety margin based on the individuals reloading process. Speer said 6% margin in 1956, for writing load manuals. I do 4% for my own loads.
There are 4 common case heads:
1) 1889 7.65x53mm Mauser case head built with large Boxer primer.
Long brass life at 68kpsi in Quickload; In 22-250, 243, 6mm Rem, 250 Savage, 257 Roberts, 25-06, 260 Rem, 6.5x55 [US made brass], 270, 7mm-08, 7x57mm, 280, 300Sav, 308, 7.62x51mm, 30-06, 8x57mm, 338F, 358, and 35W.
2) 1950 designed .222 case head with small rifle primer built with a small Boxer primer pocket will have this problem somewhere above 80kpsi in Quickload; 17 Rem, 204 Ruger, 221 Rem Fireball, .222 Rem, .223 Rem, 5.56x45mm, .222 Rem mag, 6x45mm.
3) 1925 Holland and Holland 300 H&H Magnum built with large Boxer primer will have long brass life at 72kpsi in Quickload; 6.5mm RemMag, 7mm RemMag, 8mmRemMag, 264 WinMag, 300 H&H Mag, 300 WinMag, 338 WinMag, 350 RemMag, 375 H&H Mag, 458 WinMag
4) 1889 Mauser 7.65x53mm case head design, when built with a small Boxer primer pocket will have long brass life up to primer piercing; 22BR, 6mmBR, 6x47mm, 6.5x47mm, 7mmBR, 30BR, Lapua small primer 308.
If one uses a strain gauge instead of a work up, they take on errors:
1) The error of the capriciously chosen SAAMI registered max average pressure.
2) Cannot make a measurement traceable to NIST, so measurements have no meaning. Error unknown.
The two basic errors:
1) Measuring absolute pressure is useful to the handloader.
2) Absolute pressure can be measured with a strain gauge, given the geometry of an open ended tube with a taper on the outside and a taper on the inside and a strain gauge bonding placement with out of control orientation and location.
Understanding the first error:
Registered pressures are based on the limits of the brass in strong rifles. In the first three case head designs, the primer pocket will get loose at high pressure. The goal of the work up is to find the threshold of long brass life and then back off a safety margin based on the individuals reloading process. Speer said 6% margin in 1956, for writing load manuals. I do 4% for my own loads.
There are 4 common case heads:
1) 1889 7.65x53mm Mauser case head built with large Boxer primer.
Long brass life at 68kpsi in Quickload; In 22-250, 243, 6mm Rem, 250 Savage, 257 Roberts, 25-06, 260 Rem, 6.5x55 [US made brass], 270, 7mm-08, 7x57mm, 280, 300Sav, 308, 7.62x51mm, 30-06, 8x57mm, 338F, 358, and 35W.
2) 1950 designed .222 case head with small rifle primer built with a small Boxer primer pocket will have this problem somewhere above 80kpsi in Quickload; 17 Rem, 204 Ruger, 221 Rem Fireball, .222 Rem, .223 Rem, 5.56x45mm, .222 Rem mag, 6x45mm.
3) 1925 Holland and Holland 300 H&H Magnum built with large Boxer primer will have long brass life at 72kpsi in Quickload; 6.5mm RemMag, 7mm RemMag, 8mmRemMag, 264 WinMag, 300 H&H Mag, 300 WinMag, 338 WinMag, 350 RemMag, 375 H&H Mag, 458 WinMag
4) 1889 Mauser 7.65x53mm case head design, when built with a small Boxer primer pocket will have long brass life up to primer piercing; 22BR, 6mmBR, 6x47mm, 6.5x47mm, 7mmBR, 30BR, Lapua small primer 308.
If one uses a strain gauge instead of a work up, they take on errors:
1) The error of the capriciously chosen SAAMI registered max average pressure.
2) Cannot make a measurement traceable to NIST, so measurements have no meaning. Error unknown.
itchyTF
Gold $$ Contributor
I can't speak for anyone else but I don't think anyone using a pressure system is developing loads solely on the basis of that. I expect they are developed in conjunction with the system. Even if the system doesn't provide absolute pressure, relative pressure traces still provide information that QL can't give you. Shot-to-shot variation or anomalies may provide information for debugging your loads.
I haven't figured out why pressure traces are sometimes delayed or even if it's significant. But it's information that you couldn't get otherwise.
I haven't figured out why pressure traces are sometimes delayed or even if it's significant. But it's information that you couldn't get otherwise.
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