Hidden Pressure Reading: A Method

[VinceMule]

This is a great micrometer to measure to the .0001, not expensive, and more than good enough for reloaders:

Shars 0- 1" DIGITAL READOUT DIGIT COUTNER OUTISDE MICROMETER 0.0001" CARBIDE P} | eBay

Accuracy of <0.3µm +(L(mm)/1200) µm. If you need to speak to a sales person feel free to call. Phone: 1-630-443-3244. Fitted case. Product includes. MFG SKU #303-2401.

www.ebay.com

While you are at it, a Shars Tube micrometer to measure neck thickness is also a great purchase, they never wear out.

SHARS 0-1" Tube Micrometer 0.0001" Graduation Carbide Tipped NEW P} | eBay

Accuracy of <0.3µm +(L(mm)/1200) µm. You may ask for freight cost before buying tools.

www.ebay.com

I have the very best of Brown and Sharp, Starrett, and Mitutoyo calipers that are NON-electronic. When measuring for exact dimensions, I reach for micrometers that measure to .0001. Electronic micrometers and calipers may have issues when dropped, the auto shut-off is the first problem you see when they are dropped, which in my mind makes them all "throw-away" items. The Mechanical digitals are easier to see and less apt to make a mistake in low light or those with less than perfect vision.

If you have 10 grandkids, maybe two will love and will show any interest in the fine discipline of Reloading and tinkering on guns. The balance of the grandkids will show more interest in their phones.

 

[FullCurl8]

This is a great micrometer to measure to the .0001, not expensive, and more than good enough for reloaders:

Shars 0- 1" DIGITAL READOUT DIGIT COUTNER OUTISDE MICROMETER 0.0001" CARBIDE P} | eBay

Accuracy of <0.3µm +(L(mm)/1200) µm. If you need to speak to a sales person feel free to call. Phone: 1-630-443-3244. Fitted case. Product includes. MFG SKU #303-2401.

www.ebay.com

While you are at it, a Shars Tube micrometer to measure neck thickness is also a great purchase, they never wear out.

SHARS 0-1" Tube Micrometer 0.0001" Graduation Carbide Tipped NEW P} | eBay

Accuracy of <0.3µm +(L(mm)/1200) µm. You may ask for freight cost before buying tools.

www.ebay.com

I have the very best of Brown and Sharp, Starrett, and Mitutoyo calipers that are NON-electronic. When measuring for exact dimensions, I reach for micrometers that measure to .0001. Electronic micrometers and calipers may have issues when dropped, the auto shut-off is the first problem you see when they are dropped, which in my mind makes them all "throw-away" items. The Mechanical digitals are easier to see and less apt to make a mistake in low light or those with less than perfect vision.

If you have 10 grandkids, maybe two will love and will show any interest in the fine discipline of Reloading and tinkering on guns. The balance of the grandkids will show more interest in their phones.

I think everyone needs to know that you can put a .0005 groove in a brass case with your fingernail, and that a case is the Victim, not meant to contain pressure, they aren't all created equally and softer and harder ones will give misleading evidence compared to a powder testing facility.

 

[VinceMule]

No one has done a Rockwell test on various brands of brass, which should also include testing of a number of cases within each brand of brass. This test would be a shocking revelation.

Norma
Federal
Winchester
Remington
AGD
Peterson
Lapua

Pick a caliber and stay within the caliber for all tests.

 

[wonderman4]

What kinds of speeds are you running?

Pressure equals speed and speed equals pressure

Don't get tuned onto that idea, as it ain't always the case. Matter of fact, far from it.

 

[Orange Dust]

Don't get tuned onto that idea, as it ain't always the case. Matter of fact, far from it.

Speed is an (indication) of pressure. BUT this is when you are comparing apples to apples. Test barrels are all created to min dimensions as are the chambers. Pressures tend to run higher for a given charge VS a factory rifle with looser tolerances. This is how a book can list a load of say 70grs can get 3k fps with a max load. Shooter has a factory rifle with loose tolerances and a long throat. He finds he can safely go 72grs. He may or may not exceed the 3000fps that is book max depending on how much powder burns in the barrel, expansion ratio and a whole lot of other stuff. He thinks the reloading manual is all lawyered up and publishing soft loads. Nothing could be further from the truth. This comes from many old books with references for higher, sometimes much higher charges. the old books were developed with factory guns and most weren't pressure tested, but deemed safe in the test gun. The new books have mostly pressure tested loads in a universal receiver. The trick is, once the 3000k book max is reached, chances are max pressure in the book are also getting there also. Not an absolute, but just another warning to pay attention to. You can also run the same experiment with a powder that has a completely different burn rate and get just the opposite in the same rifle. You can max out pressure wise with a load that neither reaches book max in either powder weight or velocity. Change one component from what they used in the load book (including cases) and the book only becomes a reference for starting loads. Change from a cup and core bullet to another with a different shape, or to an extreme an all copper bullet and it can get downright dangerous. Anyway a good chrono is just as important to a long range hunter as a reloading press. A chrono is great for looking for loads in another way. As you shoot a series with increasing charges, velocities will tend to stabilize near the top of the string, then they will have a rapid increase, or remain the same as more powder is added, or even drop. Usually accuracy is found at the beginning of this stabilization. There will be two shots very close in velocity with 1/2 gr difference in charge, and below pressure signs. This is where you want to start fine tuning. the best long range load will usually end up in that range for powder charge. After playing with bullet jump, if you are not there, change powder or bullet, but not both at once or you will chase your tail. You can get a good, workable load with the minimum use of components this way. Working under 500 yds is a completely different deal though. Here just whatever groups best @200. forget velocity until you are done.

 

[john k]

I have save problem with my C.A. Ridgeline 6.5 PRC. Drives me nuts. I have an MGM TC Encore full bull barrel in 6.5 PRC that I can't even get pressure signs in with 4 grains hotter than C.A..

Don't feel like the Lone Ranger. I have same issue with my C.A. Ridgeline .280AI. If it wasn't so accurate I would have sent it.

 

[Mark37082]

I've mentioned this in another thread, some bullets and powder combinations can do some strange things. I ran a pressure ladder with the Badlands BD2 150 in a 280AI. I tried Staball 6.5 in the test with new Peterson brass. Started low and increased in .5 gr increments. I went from no pressure signs to serious pressure in .5 grains (heavy bolt lift and significant ejector mark). I didn't get a reading on the Labradar on the last shot, but the previous shot was just north of 3k. I instinctively knew the 3013 fps was probably topping out, but I just had to push it for some reason. This was a couple of grains lower than what was recommended as a max load. It can spike really quickly.

 

[bill123]

If turning my own gauges, what should the diameters be for go and no go gauges on small and larger rifle primer pockets?

 

[MagnumManiac]

If you are using actual pressure test gear please publish those results for your fast and slow barrels. Outside of that, you are guessing what pressures you are developing. Of all the metrics available to the layman loader, case head and web expansion are the most accurate.

The quote below is from Hodgdon's site and they should know a bit about the subject. When you see case head expansion in the .0006 range as indicating maximum pressure, and you have primer pockets growing by .0015, or over double that, it is pretty clear that load is well past limits.

I have a pressure trace 2 system, so yes, I measure actual pressure and you can quote Hodgdon all you like…I worked at the company that makes their powder AND publishes their data…from QUICKLOAD.
I find it amazing that people BELIEVE the BS these companies tell you…have you seen their testing equipment? I don't think so.
Also, I WILL NOT publish my data, it is of no use to you, you will believe a company that says they make powder…which they do not!

Cheers.

 

[Dean2]

Int

I have a pressure trace 2 system, so yes, I measure actual pressure and you can quote Hodgdon all you like…I worked at the company that makes their powder AND publishes their data…from QUICKLOAD.
I find it amazing that people BELIEVE the BS these companies tell you…have you seen their testing equipment? I don't think so.
Also, I WILL NOT publish my data, it is of no use to you, you will believe a company that says they make powder…which they do not!

Cheers.

Interesting. I think pretty much everyone knows that Hodgdon has powder made by a large number of manufacturers and that they distribute these powders under the brand names they own. Hodgdon has made no secret of this, it is right on their website, as is the history of the company. It is also clear from their site that they have about 100 employees, so I doubt anyone thinks they actually produce all their own powder.

Your assertions that their published load data is derived from Quickload is brand new information to me. Frankly, I don't believe that but in the interest of expanding my knowledge, I cut and pasted your repsonse and allegations and sent them to Hornady. I will be very interested to hear their take on your assertions about how they derive their pressure data. It doesn't match previous correspondence and phone calls I have had with them so I Will be VERY interested to hear if you are right.

 

[VinceMule]

I cut and pasted your repsonse and allegations and sent them to Hornady. I will be very interested to hear their take on your assertions about how they derive their pressure data. It doesn't match previous correspondence and phone calls I have had with them so I Will be VERY interested to hear if you are right.

Waste of time. You heard it from the Horse's mouth, Magnum Mania is no Bull sheeter.

 

[MagnumManiac]

Int

Interesting. I think pretty much everyone knows that Hodgdon has powder made by a large number of manufacturers and that they distribute these powders under the brand names they own. Hodgdon has made no secret of this, it is right on their website, as is the history of the company. It is also clear from their site that they have about 100 employees, so I doubt anyone thinks they actually produce all their own powder.

Your assertions that their published load data is derived from Quickload is brand new information to me. Frankly, I don't believe that but in the interest of expanding my knowledge, I cut and pasted your repsonse and allegations and sent them to Hornady. I will be very interested to hear their take on your assertions about how they derive their pressure data. It doesn't match previous correspondence and phone calls I have had with them so I Will be VERY interested to hear if you are right.

Again, you believe they HAVE powder made for THEM, this is so far from the truth that it is laughable.
The fact is, they ONLY have distribution and branding rights. PERIOD!
I will show you where their data comes from.

 

[cape cove]

Guys, is it possible to have occasional stick bolt lift and not have high pressure.

 

[asd9055]

Again, you believe they HAVE powder made for THEM, this is so far from the truth that it is laughable.
The fact is, they ONLY have distribution and branding rights. PERIOD!
I will show you where their data comes from.

Tony, do you by any chance have a list of which ADI powders have exact equivalent in Hodgdon, IMR or other? I see table on the ADI webdsite, but not sure which ADI are sold by another "name"