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Powder Question
- Thread starter Cola308
- Start date
Don Fischer
New member
Just start low with either. You'll find that a lot of manuals disagree with each other but really they don't. They didn't test in the same firearm on the same day with like condition's and like lot number's of powder. Each was right for what they did. No load is perfect for all loads but all load data was perfect at the time the test was done in the firearm it was done in!
I agree with the above when the differences are minor. But, while at one time folks used reloading guides that were paper books, proof-read and checked over and over. Today, a lot of reloading info comes from "the net", often posted by someone with little or no experience and not checked by anyone. I don't say not to use it, but it is best to consult other sources, including one's own experience, and use a healthy does of common sense.
Jim
Jim
Stats Shooter
New member
Yup. I affirm the last two posts. I have had the same thing happen many times.
Just pick a minimum, the one that most closely resembles your load, i.e. Winchester primers or federal, and the case if you can find that info out.
If you can't find out, you can always just pick the lowest minimum and pressure test a few loads up to the higher minimum.
Just pick a minimum, the one that most closely resembles your load, i.e. Winchester primers or federal, and the case if you can find that info out.
If you can't find out, you can always just pick the lowest minimum and pressure test a few loads up to the higher minimum.
ShootistPRS
New member
Bullet manufacturers loads are based on the bullets they make and the cases they choose to use. The load could be an overload in another case or in the same case with a different bullet. In the far away past all bullets were made pretty much the same way but today bullet materials and jacket thicknesses vary so much that you have to be very careful. Cases are another BIG variable. It used to be if you used military brass you reduced the load by 10% but if you were using other brass it was far less important. Now we have reduced capacity 9mm cases and the +P cases for 257 that have drastically lower case capacities than even the heaviest "standard" cartridge. I recently made up some test cases for my 257 Roberts using data from three different sources. I was working with standard load data and not the higher pressure +P loads. At the range I got hard bolt lift with starting loads so I stopped to figure out what was wrong.I pulled the bullets and weighed the charges and they were at minimum. I examined the cases and found that they were the +P cases. I looked up the +P loads and found that my minimum loads were a full grain over the maximum loads in +P cases. The +P cases have less capacity than the standard case. I removed all the bullets, powder and primers and switched to the standard cases. I have separated the +P cases and will deal with them like I would for a different bullet or powder.
You have to be ever vigilant because there are a number of new bullets and cases than can effect pressures.
You have to be ever vigilant because there are a number of new bullets and cases than can effect pressures.
disseminator
New member
Are you by chance talking about Hornady?
Their data is pretty conservative but I suggest you trust it because in my experience Hornady bullets, at least the XTP and HAP that I use, DO create more pressure than other bullets and so can't be driven as fast as some other bullets with the same pressures.
And then there is the different brass and etc already discussed.
Their data is pretty conservative but I suggest you trust it because in my experience Hornady bullets, at least the XTP and HAP that I use, DO create more pressure than other bullets and so can't be driven as fast as some other bullets with the same pressures.
And then there is the different brass and etc already discussed.
Testing every single load right to max takes lots of time. If manual "A" says 45gr is is a max load and manual "B" says 47 gr is max load it is often simply because the company who printed manual "A" simply stopped testing at 45 gr and the company who printed manual "B" continued to push it farther and determined that 47 gr was safe.
I let my chronograph tell me where to stop adding powder.
I let my chronograph tell me where to stop adding powder.
Do chronographs now have readings for chamber pressure?I let my chronograph tell me where to stop adding powder.
Stats Shooter
New member
Do chronographs now have readings for chamber pressure?
No of course not. But, as pressure increases, velocity Increases. However, the relationship, while positively correlated, may not have a direct correlation coefficient of 1.... mainly because the pressure curve may be longer or shorter depending on the amount of powder, and of course a different peak.
A longer curve increases velocity , as does a higher peak. But a higher peak is where the concern lies.
Then, you have the fact that chambers, cases, barrels etc are all different. Which means the published pressure for a stated combo of powder, primer, bullet, and case may differ from the actual....oh lot variation on some of the above.
Therefore, you can't use a chronograph to deduce pressure at the margins. But a chronograph can indicate if you are well over pressure, or well below MAP. And,the chronograph can help build a relationship to increased powder and pressure. For example an additional 0.3 gr increases your .233 load 25 fps or something....then using Quickload I can estimate how much my pressure increased to attain that velocity increase.
Furthermore, I will use a chronograph, then my chamber/case specs, and Quickload to estimate my loads pressure.
So, no, a chronograph cannot directly tell you what your pressure is, but it can help deduce it with accompaniment of other sources.
The powder companies and the bullet companies did their tests on different days using different components and firearms. Both sets of results are safe.
However, if I used either data sets, it'd be the powder maker's. Even then you'll find discrepancies. It's worse on the assorted on-line data pages. Hodgdon, for instance, says they tested .38 Special with a 7.7" barrel. Not many of those around. Jacks up velocities too. And they says to use magnum primers only for magnum named cartridges.
However, if I used either data sets, it'd be the powder maker's. Even then you'll find discrepancies. It's worse on the assorted on-line data pages. Hodgdon, for instance, says they tested .38 Special with a 7.7" barrel. Not many of those around. Jacks up velocities too. And they says to use magnum primers only for magnum named cartridges.
I agree with the above when the differences are minor. But, while at one time folks used reloading guides that were paper books, proof-read and checked over and over. Today, a lot of reloading info comes from "the net", often posted by someone with little or no experience and not checked by anyone. I don't say not to use it, but it is best to consult other sources, including one's own experience, and use a healthy does of common sense.
That veers off the issue of published data the OP asked be it internet by the powder mfgs (or paper pubs) or the bullet maker manuals.
To put it simply Coaloa38:
1. Use of any published low is fine as long as its really a low.
Its the high you have to worry about.
That said if you found a complete bust where a low was so high to be up at the upper end or higher than another source, then that low is a typo.
That's why you want Two Sources. Consult a third if there is a bust or go with the conservative source and note the bust.
I use two primarily, I have about 6 around the house, some very old and some bought on sale when new editions come out.
I keep what I think is the best latest one and that is Hornady up to date.
One back I keep by the computer for reference in discussions (actually two, Lymans and my Edition 9 or Hornady .
I will also note, in the past its always been almost impossible to get a typo out of a publication.
Its easier now in that its electronic and if the editions repeated (5th publish if Edition 1) , the mfg (Powder or Bullet) if they are interested, can change it easily.
Don Fischer
New member
Something I forgot to mention is what firearm was used in working up the load by whoever put out the manual. Only one instance I'm aware of is Hornady's data for a 6.5x55. They used a mod 93, maybe it was 96, mauser to develop the loads and the loads are very light for modern firearms. In that situation I found the load with a 125 gr Nosler and used that data to develop a load for the 129gr Hornady. Word of caution, in a situation like that start low and work up, don't fool with that. And if you are shooting a 93 or 96 Mauser, use the Hornady data and work up. I think most will disagree with me on this but it is what I do. Speer has 120gr data but bullet is to light for me to fool with that data.
A bit puzzled but.
There are a range of guns out there that are not modern.
Mauser is one, 7.5 Swiss is another, Old Revolvers another group, as many of the cartridges are quite old, that's not unusual.
The firearm used is listed in the bullet mfgs. Lymans has sub sections for various types when they are both popular and old.
If you are dealing with old guns you should have some idea it needs caution and do your research accordingly.
I have a7.5 Swiss in a Savage that I will push further than the 1911/K31 loadings.
I know not to put those loads in those guns.
There are a range of guns out there that are not modern.
Mauser is one, 7.5 Swiss is another, Old Revolvers another group, as many of the cartridges are quite old, that's not unusual.
The firearm used is listed in the bullet mfgs. Lymans has sub sections for various types when they are both popular and old.
If you are dealing with old guns you should have some idea it needs caution and do your research accordingly.
I have a7.5 Swiss in a Savage that I will push further than the 1911/K31 loadings.
I know not to put those loads in those guns.
"Do chronographs now have readings for chamber pressure?"
No, they don't. However if you compare the top load for whatever cartridge you're shooting using say one of the 4831s showing a max load of 57 gr. and 2950 FPS average in say three manuals for the bullet weight you want to use, say a 150 gr. .270 then a chronograph reading that shows that speed or close to it is saying it may be time to quit.
Another thing you can do is record the shots from each work up load. Powder is design to burn properly between a high and low pressure range. Start within the required low range and as you go higher the velocity will increase on a linear basis. Once the pressure reaches it's upper limit velocity will do one of three things. make a massive jump in speed, or not increase at all or actually slow down by a noticeable amount. Any one of the three is a warning to back off right now. Usually one half to one and a half grains has worked for me. I generally try to drop at least one full grain 99 percent of the time. Depends what I'm shooting.
One thing to remember is if you've matched the average velocity from several book loads, and it seems like you could go higher, it's still the best place to call for a stop. Granted, certain cartridges have been under loaded by the factories and manuals for safety reasons (mostly old weak guns) most if not all modern rounds are loaded pretty close to the safe maximum for that cartridge. It's best to not try beating them for speed.
Paul B.
No, they don't. However if you compare the top load for whatever cartridge you're shooting using say one of the 4831s showing a max load of 57 gr. and 2950 FPS average in say three manuals for the bullet weight you want to use, say a 150 gr. .270 then a chronograph reading that shows that speed or close to it is saying it may be time to quit.
Another thing you can do is record the shots from each work up load. Powder is design to burn properly between a high and low pressure range. Start within the required low range and as you go higher the velocity will increase on a linear basis. Once the pressure reaches it's upper limit velocity will do one of three things. make a massive jump in speed, or not increase at all or actually slow down by a noticeable amount. Any one of the three is a warning to back off right now. Usually one half to one and a half grains has worked for me. I generally try to drop at least one full grain 99 percent of the time. Depends what I'm shooting.
One thing to remember is if you've matched the average velocity from several book loads, and it seems like you could go higher, it's still the best place to call for a stop. Granted, certain cartridges have been under loaded by the factories and manuals for safety reasons (mostly old weak guns) most if not all modern rounds are loaded pretty close to the safe maximum for that cartridge. It's best to not try beating them for speed.
Paul B.
post # 2 nailed it
start low work up gradually and look for pressure signs and back off if you even think you sense anything suggesting over pressure. no need to over complicate what is essentially common sense. If you don't know what over pressure signs look like or feel like then err on the conservative side until you learn
start low work up gradually and look for pressure signs and back off if you even think you sense anything suggesting over pressure. no need to over complicate what is essentially common sense. If you don't know what over pressure signs look like or feel like then err on the conservative side until you learn
When loading plated bullets in either rifle or handgun I first go the bullet manufacturer' loading data. Different brands of plated bullets can have slightly higher friction plating, harder plating or thicker or thinner plating than the same bullet weight and configuration of another brand. I noticed long ago that Sierra bullets invariably called for heavier charges in their manual than Hornady or Speer did in their manuals. I have always gone to the bullet maker's manual first, then consulted others to come up with a load that was safe in all manuals. Admittedly I have always been a conservative loader and will never load a absolutely maximum charge. My view is if I need to do that I need a larger caliber.
I trust the powder company more than the bullet company....and I make sure I check the powder company's online current data over any published book.
Hodgdon has a good website as an example...
I would not use data from internet forum members - although there is a lot of experience on here and other sites on a variety of things, be suspicious of load data....they mean well...but some of them "wildcat" things...and you don't really know them personally.
Hodgdon has a good website as an example...
I would not use data from internet forum members - although there is a lot of experience on here and other sites on a variety of things, be suspicious of load data....they mean well...but some of them "wildcat" things...and you don't really know them personally.
Bullet company, powder company, or just a reloading company--they all agreed to voluntarily follow SAAMI testing guidelines.
Many manual show the pressure for the max loads and you'll still see big spreads.
Unless someone tested YOUR gun and you lot of powder and you lot of bullets and the same brand of cases and primers at the same COL, expect differences.
I find the safest things is to always check multiple sources and start at the lowest start load.
You simply don't know how your mix of components will act compared to what any of the manuals used.
Many manual show the pressure for the max loads and you'll still see big spreads.
Unless someone tested YOUR gun and you lot of powder and you lot of bullets and the same brand of cases and primers at the same COL, expect differences.
I find the safest things is to always check multiple sources and start at the lowest start load.
You simply don't know how your mix of components will act compared to what any of the manuals used.
They do --pretty much-- when married up with an intelligent QuickLoad userDo chronographs now have readings for chamber pressure?Quote:
I let my chronograph tell me where to stop adding powder.
... big time.