pressure test
- Thread starter Prebanpaul
- Start date
Re: pressure test
Strain gauge city is where it is at...and you'd need a statistically valid number of rounds fired in YOUR rifle. I'd think a valid ladder test working toward a node rather than trying to get a quart out of a pint pot might be more rewarding. JMHO
Strain gauge city is where it is at...and you'd need a statistically valid number of rounds fired in YOUR rifle. I'd think a valid ladder test working toward a node rather than trying to get a quart out of a pint pot might be more rewarding. JMHO
Re: pressure test
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Prebanpaul</div><div class="ubbcode-body">anywhere to send a round that you have reloaded to figure out the psi of the round </div></div>
Prebanpaul,
I know this is getting a little bit old but RSI has a good pressure measurement system for $500. Look here: <span style="font-weight: bold"><span style="color: #000099">RSI Pressure Trace System</span></span>
HTH!
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Prebanpaul</div><div class="ubbcode-body">anywhere to send a round that you have reloaded to figure out the psi of the round </div></div>
Prebanpaul,
I know this is getting a little bit old but RSI has a good pressure measurement system for $500. Look here: <span style="font-weight: bold"><span style="color: #000099">RSI Pressure Trace System</span></span>
HTH!
Re: pressure test
Are you looking for something more accurate than the calculated psi in quick load?
Are you looking for something more accurate than the calculated psi in quick load?
Re: pressure test
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 1911GunNut</div><div class="ubbcode-body">Are you looking for something more accurate than the calculated psi in quick load? </div></div>
I've been using QL for some time and QL does not seem particularly useful in terms of predicting actual pressure. I have seen clear signs of being over pressure in loads that QL says should be reasonable. But the cool thing is that as long as I keep my load predicted by QL under 57K psi I get no signs of pressure at all. Interestingly enough QL's predicted velocities match up very well, within +/- 10fps fired over my PVM21 chronograph once I measured the water grains of the cases I'm using.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 1911GunNut</div><div class="ubbcode-body">Are you looking for something more accurate than the calculated psi in quick load? </div></div>
I've been using QL for some time and QL does not seem particularly useful in terms of predicting actual pressure. I have seen clear signs of being over pressure in loads that QL says should be reasonable. But the cool thing is that as long as I keep my load predicted by QL under 57K psi I get no signs of pressure at all. Interestingly enough QL's predicted velocities match up very well, within +/- 10fps fired over my PVM21 chronograph once I measured the water grains of the cases I'm using.
Re: pressure test
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: YAOG</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 1911GunNut</div><div class="ubbcode-body">Are you looking for something more accurate than the calculated psi in quick load? </div></div>
I've been using QL for some time and QL does not seem particularly useful in terms of predicting actual pressure. I have seen clear signs of being over pressure in loads that QL says should be reasonable. But the cool thing is that as long as I keep my load predicted by QL under 56K psi I get no signs of pressure at all. Interestingly enough QL's predicted velocities match up very well, within +/- 10fps fired over my PVM21 chronograph once I measured the water grains of the cases I'm using.
</div></div>
Exactly, You have to have everything inputted to what the actual numbers are. The velocities do match up very well for me too.
Don't forget temperature, that can be a big variance, since you aren't really measuring outside temperature, but temperature of the powder in the case right before you fire. If you've been shooting then let the round sit in the chamber for awhile before shooting, it'll be hotter than outside temp, which will throw off all the numbers.
I just use the PSI in quick load as a starting guide, no substitute for checking for pressure signs when load testing.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: YAOG</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 1911GunNut</div><div class="ubbcode-body">Are you looking for something more accurate than the calculated psi in quick load? </div></div>
I've been using QL for some time and QL does not seem particularly useful in terms of predicting actual pressure. I have seen clear signs of being over pressure in loads that QL says should be reasonable. But the cool thing is that as long as I keep my load predicted by QL under 56K psi I get no signs of pressure at all. Interestingly enough QL's predicted velocities match up very well, within +/- 10fps fired over my PVM21 chronograph once I measured the water grains of the cases I'm using.
</div></div>
Exactly, You have to have everything inputted to what the actual numbers are. The velocities do match up very well for me too.
Don't forget temperature, that can be a big variance, since you aren't really measuring outside temperature, but temperature of the powder in the case right before you fire. If you've been shooting then let the round sit in the chamber for awhile before shooting, it'll be hotter than outside temp, which will throw off all the numbers.
I just use the PSI in quick load as a starting guide, no substitute for checking for pressure signs when load testing.
Re: pressure test
<span style="font-style: italic">"Strain gauge city is where it is at...and you'd need a statistically valid number of rounds fired in YOUR rifle."</span>
That's true, probably needs about 25 rounds to establish a good working average. Not only do individual rounds of 'identical' loads vary somewhat but so does the measurement equipment itself - and the skill of the tester too. Then the collected data are ONLY valid for that firearm and at that ambient temperature.
<span style="font-style: italic">"Strain gauge city is where it is at...and you'd need a statistically valid number of rounds fired in YOUR rifle."</span>
That's true, probably needs about 25 rounds to establish a good working average. Not only do individual rounds of 'identical' loads vary somewhat but so does the measurement equipment itself - and the skill of the tester too. Then the collected data are ONLY valid for that firearm and at that ambient temperature.
Re: pressure test
Pressure matters for selling ammo, but not necessarily for hand loaders.
What would you do with a number, compare it to SAAMI registration?
What would that do for you?
Pressure matters for selling ammo, but not necessarily for hand loaders.
What would you do with a number, compare it to SAAMI registration?
What would that do for you?
Re: pressure test
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">Pressure matters for selling ammo, but not necessarily for hand loaders.
What would you do with a number, compare it to SAAMI registration?
What would that do for you? </div></div>
You could more easily and more safely find the highest velocity node for a particular load and barrel. You will waste much less time and fewer materials and have a tool to quantify safe pressure limits instead of guessing. With this information you could become a better shooter because you won't need to waste as much time guessing what the limits of your powder charge should be and where to begin working on OCW for a given weapon.
Aside from these things noting.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">Pressure matters for selling ammo, but not necessarily for hand loaders.
What would you do with a number, compare it to SAAMI registration?
What would that do for you? </div></div>
You could more easily and more safely find the highest velocity node for a particular load and barrel. You will waste much less time and fewer materials and have a tool to quantify safe pressure limits instead of guessing. With this information you could become a better shooter because you won't need to waste as much time guessing what the limits of your powder charge should be and where to begin working on OCW for a given weapon.
Aside from these things noting.
Re: pressure test
1) Accurate pressure measurement matters if one is going to sell ammunition.
2) Accurate pressure measurement matters if a gun is weaker than the brass.
3) For me, considering myself an advanced reloader, with a strong rifle [huge amounts of safety margin due to thick steel], knowing the pressure is red herring. What matters is the effects of pressure.
a) If the weakest link is the primer piercing, the load needs to be backed off from the threshold of primer piercing.
b) If the weakest link is getting loose primer pockets, the load needs to be backed off from the threshold of loose primer pockets.
c) If the weakest link is stiff bolt lift, the load needs to be backed off from the threshold of stiff bolt lift.
d) If the weakest link is the brass flowing into the bolt face in the extractor or ejector cuts, the load needs to be backed off from that threshold.
e) If the weakest link is a non adjustable gas system and the bolt carrier is slamming into the receiver and the brass is ejected a long way, the load needs to be backed off from that threshold.
f) If the weakest link is a recoil operated system that the bolt carrier slams into the receiver, the load needs to be backed off from that threshold.
g) etc.
It has been my experience with Ruger #1 .223s the the weakest link is loose primer pockets.
One can put in another primer to see if the pocket is loose, but I have found a better way. I measure the extractor groove before and after firing. I measure all the way around. In a load work up, the change in extractor groove is easily measured precisely enough with dial calipers. Any change at all may not make the next primer seem any easier to insert, but the threshold is very close. Hoping to see a primer fall out as a pressure sign in a work up is more crude than feeling insertion force.
pic left to right: unfired, 28, 29, 30, and 31 gr.
Hodgdon website: 223 Rem, H335, 25.3 GR. 55 GR. SPR SP, 2.200", 24"barrel, 3203 fps, 49,300 CUP
Test: Ruger #1, CCI 400 small rifle primers, LC brass once firedprocessed from Scharch and prepped by me, 55 gr Vmax moly, H335 unfired, extractor groove .329"
28 gr, extractor groove .329", 11% overload 69 kpsi [QL]
29 gr, extractor groove .329", 15% overload 80kpsi [QL]
30 gr, extractor groove .3295", 19% overload 92kpsi [QL]
31 gr, extractor groove .3320", 23% overload 106kpsi [QL]
What does it all mean?
I predict that the threshold of loose primer pockets is somewhere between 29 and 30 gr. I would do another more detailed work up and find the threshold more accurately. I would then subtract a safety margin for temperature variations in that powder, my reloading process variations, component variation, etc.
Vernon Speer said in 1956 that he backs off 6% Powder charge from brass change. I have found i can use a 4% margin for Hodgdon extreme powders.
What does THAT man?
223 is SAAMI registered at 55kpsi, which is a long away from it's useful max pressure [>75kpsi QL] that advanced reloaders can exploit.
Contrast that with .270 that is SAAMI registered at 65kpsi, that has a long brass life pressure threshold [>67kpsi QL] very close to the same. There is no excess margin to exploit.
1) Accurate pressure measurement matters if one is going to sell ammunition.
2) Accurate pressure measurement matters if a gun is weaker than the brass.
3) For me, considering myself an advanced reloader, with a strong rifle [huge amounts of safety margin due to thick steel], knowing the pressure is red herring. What matters is the effects of pressure.
a) If the weakest link is the primer piercing, the load needs to be backed off from the threshold of primer piercing.
b) If the weakest link is getting loose primer pockets, the load needs to be backed off from the threshold of loose primer pockets.
c) If the weakest link is stiff bolt lift, the load needs to be backed off from the threshold of stiff bolt lift.
d) If the weakest link is the brass flowing into the bolt face in the extractor or ejector cuts, the load needs to be backed off from that threshold.
e) If the weakest link is a non adjustable gas system and the bolt carrier is slamming into the receiver and the brass is ejected a long way, the load needs to be backed off from that threshold.
f) If the weakest link is a recoil operated system that the bolt carrier slams into the receiver, the load needs to be backed off from that threshold.
g) etc.
It has been my experience with Ruger #1 .223s the the weakest link is loose primer pockets.
One can put in another primer to see if the pocket is loose, but I have found a better way. I measure the extractor groove before and after firing. I measure all the way around. In a load work up, the change in extractor groove is easily measured precisely enough with dial calipers. Any change at all may not make the next primer seem any easier to insert, but the threshold is very close. Hoping to see a primer fall out as a pressure sign in a work up is more crude than feeling insertion force.
pic left to right: unfired, 28, 29, 30, and 31 gr.
Hodgdon website: 223 Rem, H335, 25.3 GR. 55 GR. SPR SP, 2.200", 24"barrel, 3203 fps, 49,300 CUP
Test: Ruger #1, CCI 400 small rifle primers, LC brass once firedprocessed from Scharch and prepped by me, 55 gr Vmax moly, H335 unfired, extractor groove .329"
28 gr, extractor groove .329", 11% overload 69 kpsi [QL]
29 gr, extractor groove .329", 15% overload 80kpsi [QL]
30 gr, extractor groove .3295", 19% overload 92kpsi [QL]
31 gr, extractor groove .3320", 23% overload 106kpsi [QL]
What does it all mean?
I predict that the threshold of loose primer pockets is somewhere between 29 and 30 gr. I would do another more detailed work up and find the threshold more accurately. I would then subtract a safety margin for temperature variations in that powder, my reloading process variations, component variation, etc.
Vernon Speer said in 1956 that he backs off 6% Powder charge from brass change. I have found i can use a 4% margin for Hodgdon extreme powders.
What does THAT man?
223 is SAAMI registered at 55kpsi, which is a long away from it's useful max pressure [>75kpsi QL] that advanced reloaders can exploit.
Contrast that with .270 that is SAAMI registered at 65kpsi, that has a long brass life pressure threshold [>67kpsi QL] very close to the same. There is no excess margin to exploit.
Re: pressure test
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">1) Accurate pressure measurement matters if one is going to sell ammunition. </div></div>
Pressure and the effects of pressure matter for all handloaders. If the handloader knew with certainty that a particularly accurate load was at or past the safe pressure limit of the components used the handloader could make intelligent decisions about the load without having to resort to guessing about the safety of a load.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">2) Accurate pressure measurement matters if a gun is weaker than the brass.</div></div>
This statement is incorrect. All brass is weaker than the steel used in gun barrels. To the best of my knowledge there are no commercially built rifles that cannot be damaged or overloaded by improperly loaded ammunition.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">3) For me, considering myself an advanced reloader, with a strong rifle [huge amounts of safety margin due to thick steel], knowing the pressure is red herring. What matters is the effects of pressure.</div></div>
I'm happy to hear that in your opinion you are an advanced reloader. I learn something new everyday. Guessing safe load pressure limits is exactly that, guessing. It's called guessing because you lack any actual instrumented data.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">a) If the weakest link is the primer piercing, the load needs to be backed off from the threshold of primer piercing.</div></div>
If you are piercing primers more than likely there is a firearm problem frequently a poorly shaped firing pin, weak firing pin spring, out of spec headspace with handloads that are incorrectly sized for the out of spec headspace.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">b) If the weakest link is getting loose primer pockets, the load needs to be backed off from the threshold of loose primer pockets.</div></div>
Loose primer pockets are typically caused by excessively high chamber pressure or using cases made of soft brass. Additionally if you are uniforming your primer pockets the uniforming cutting tool could be out of spec.
With a pressure testing instrument you would know if the problem is being caused by excessive pressure or bad out of spec brass. You could also change the brand of cases used and or not uniform the primer pockets to see if the problem continues or not.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">c) If the weakest link is stiff bolt lift, the load needs to be backed off from the threshold of stiff bolt lift.</div></div>
This one is usually correct but can also be caused by lack of grease on lugs, previous over pressure loads causing gauling of the bolt lugs and mating surfaces in the chamber.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">d) If the weakest link is the brass flowing into the bolt face in the extractor or ejector cuts, the load needs to be backed off from that threshold.</div></div>
This is sometimes correct with the exceptions of out of spec headspace or incorrectly formed handloads for the out of spec chamber. If the firearm chamber is within SAAMI specs per a go-no no-go gauge chances are the problem was excessive pressure.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">e) If the weakest link is a non adjustable gas system and the bolt carrier is slamming into the receiver and the brass is ejected a long way, the load needs to be backed off from that threshold.</div></div>
I'm mostly a bolt gun guy and this sounds almost correct. This issue can also be caused by using an incorrect or bad buffer in AR platform weapons. IMO for the most part adjustable gas blocks are most useful for civilian weapons that are out of spec somewhere, reloaded ammo that is out of spec or using lighter or heavier bolt assemblies with an inappropriate buffer.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">f) If the weakest link is a recoil operated system that the bolt carrier slams into the receiver, the load needs to be backed off from that threshold.</div></div>
See previous comment. Learn to load within pressure spec of weapon. If using factory ammo with a locking delayed bolt this could be a weapon timing issue.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">g) etc.
It has been my experience with Ruger #1 .223s the the weakest link is loose primer pockets.
One can put in another primer to see if the pocket is loose, but I have found a better way. I measure the extractor groove before and after firing. I measure all the way around. In a load work up, the change in extractor groove is easily measured precisely enough with dial calipers. Any change at all may not make the next primer seem any easier to insert, but the threshold is very close. Hoping to see a primer fall out as a pressure sign in a work up is more crude than feeling insertion force. </div></div>
See solution B.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">
pic left to right: unfired, 28, 29, 30, and 31 gr.
Hodgdon website: 223 Rem, H335, 25.3 GR. 55 GR. SPR SP, 2.200", 24"barrel, 3203 fps, 49,300 CUP
Test: Ruger #1, CCI 400 small rifle primers, LC brass once firedprocessed from Scharch and prepped by me, 55 gr Vmax moly, H335 unfired, extractor groove .329"
28 gr, extractor groove .329", 11% overload 69 kpsi [QL]
29 gr, extractor groove .329", 15% overload 80kpsi [QL]
30 gr, extractor groove .3295", 19% overload 92kpsi [QL]
31 gr, extractor groove .3320", 23% overload 106kpsi [QL]
What does it all mean?
I predict that the threshold of loose primer pockets is somewhere between 29 and 30 gr. I would do another more detailed work up and find the threshold more accurately. I would then subtract a safety margin for temperature variations in that powder, my reloading process variations, component variation, etc.
Vernon Speer said in 1956 that he backs off 6% Powder charge from brass change. I have found i can use a 4% margin for Hodgdon extreme powders.
What does THAT man?
223 is SAAMI registered at 55kpsi, which is a long away from it's useful max pressure [>75kpsi QL] that advanced reloaders can exploit.
Contrast that with .270 that is SAAMI registered at 65kpsi, that has a long brass life pressure threshold [>67kpsi QL] very close to the same. There is no excess margin to exploit. </div></div>
It means you are trying to extend the capability of the .223 cartridge beyond safe cartridge and weapon specs. to gain some sort of advantage so you can use a weapon in the wrong caliber for the job at hand.
It means you are guessing about pressure based on QuickLOAD software simulation instead of using appropriate hardware pressure testing instruments.
It means you should move up to a cartridge and caliber that is appropriate for the job that allows you to work within the specs for that cartridge.
HTH!
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">1) Accurate pressure measurement matters if one is going to sell ammunition. </div></div>
Pressure and the effects of pressure matter for all handloaders. If the handloader knew with certainty that a particularly accurate load was at or past the safe pressure limit of the components used the handloader could make intelligent decisions about the load without having to resort to guessing about the safety of a load.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">2) Accurate pressure measurement matters if a gun is weaker than the brass.</div></div>
This statement is incorrect. All brass is weaker than the steel used in gun barrels. To the best of my knowledge there are no commercially built rifles that cannot be damaged or overloaded by improperly loaded ammunition.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">3) For me, considering myself an advanced reloader, with a strong rifle [huge amounts of safety margin due to thick steel], knowing the pressure is red herring. What matters is the effects of pressure.</div></div>
I'm happy to hear that in your opinion you are an advanced reloader. I learn something new everyday. Guessing safe load pressure limits is exactly that, guessing. It's called guessing because you lack any actual instrumented data.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">a) If the weakest link is the primer piercing, the load needs to be backed off from the threshold of primer piercing.</div></div>
If you are piercing primers more than likely there is a firearm problem frequently a poorly shaped firing pin, weak firing pin spring, out of spec headspace with handloads that are incorrectly sized for the out of spec headspace.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">b) If the weakest link is getting loose primer pockets, the load needs to be backed off from the threshold of loose primer pockets.</div></div>
Loose primer pockets are typically caused by excessively high chamber pressure or using cases made of soft brass. Additionally if you are uniforming your primer pockets the uniforming cutting tool could be out of spec.
With a pressure testing instrument you would know if the problem is being caused by excessive pressure or bad out of spec brass. You could also change the brand of cases used and or not uniform the primer pockets to see if the problem continues or not.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">c) If the weakest link is stiff bolt lift, the load needs to be backed off from the threshold of stiff bolt lift.</div></div>
This one is usually correct but can also be caused by lack of grease on lugs, previous over pressure loads causing gauling of the bolt lugs and mating surfaces in the chamber.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">d) If the weakest link is the brass flowing into the bolt face in the extractor or ejector cuts, the load needs to be backed off from that threshold.</div></div>
This is sometimes correct with the exceptions of out of spec headspace or incorrectly formed handloads for the out of spec chamber. If the firearm chamber is within SAAMI specs per a go-no no-go gauge chances are the problem was excessive pressure.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">e) If the weakest link is a non adjustable gas system and the bolt carrier is slamming into the receiver and the brass is ejected a long way, the load needs to be backed off from that threshold.</div></div>
I'm mostly a bolt gun guy and this sounds almost correct. This issue can also be caused by using an incorrect or bad buffer in AR platform weapons. IMO for the most part adjustable gas blocks are most useful for civilian weapons that are out of spec somewhere, reloaded ammo that is out of spec or using lighter or heavier bolt assemblies with an inappropriate buffer.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">f) If the weakest link is a recoil operated system that the bolt carrier slams into the receiver, the load needs to be backed off from that threshold.</div></div>
See previous comment. Learn to load within pressure spec of weapon. If using factory ammo with a locking delayed bolt this could be a weapon timing issue.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">g) etc.
It has been my experience with Ruger #1 .223s the the weakest link is loose primer pockets.
One can put in another primer to see if the pocket is loose, but I have found a better way. I measure the extractor groove before and after firing. I measure all the way around. In a load work up, the change in extractor groove is easily measured precisely enough with dial calipers. Any change at all may not make the next primer seem any easier to insert, but the threshold is very close. Hoping to see a primer fall out as a pressure sign in a work up is more crude than feeling insertion force. </div></div>
See solution B.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">
pic left to right: unfired, 28, 29, 30, and 31 gr.
Hodgdon website: 223 Rem, H335, 25.3 GR. 55 GR. SPR SP, 2.200", 24"barrel, 3203 fps, 49,300 CUP
Test: Ruger #1, CCI 400 small rifle primers, LC brass once firedprocessed from Scharch and prepped by me, 55 gr Vmax moly, H335 unfired, extractor groove .329"
28 gr, extractor groove .329", 11% overload 69 kpsi [QL]
29 gr, extractor groove .329", 15% overload 80kpsi [QL]
30 gr, extractor groove .3295", 19% overload 92kpsi [QL]
31 gr, extractor groove .3320", 23% overload 106kpsi [QL]
What does it all mean?
I predict that the threshold of loose primer pockets is somewhere between 29 and 30 gr. I would do another more detailed work up and find the threshold more accurately. I would then subtract a safety margin for temperature variations in that powder, my reloading process variations, component variation, etc.
Vernon Speer said in 1956 that he backs off 6% Powder charge from brass change. I have found i can use a 4% margin for Hodgdon extreme powders.
What does THAT man?
223 is SAAMI registered at 55kpsi, which is a long away from it's useful max pressure [>75kpsi QL] that advanced reloaders can exploit.
Contrast that with .270 that is SAAMI registered at 65kpsi, that has a long brass life pressure threshold [>67kpsi QL] very close to the same. There is no excess margin to exploit. </div></div>
It means you are trying to extend the capability of the .223 cartridge beyond safe cartridge and weapon specs. to gain some sort of advantage so you can use a weapon in the wrong caliber for the job at hand.
It means you are guessing about pressure based on QuickLOAD software simulation instead of using appropriate hardware pressure testing instruments.
It means you should move up to a cartridge and caliber that is appropriate for the job that allows you to work within the specs for that cartridge.
HTH!
Re: pressure test
1) yada yada
2) If I work up a load unil the brass fails, some guns blow up first, some don't.
I have tested hundred of guns this way.
It is very important catogorization.
3) yada yada
a)<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">If you are piercing primers more than likely there is a firearm problem frequently a poorly shaped firing pin, weak firing pin spring, out of spec headspace with handloads that are incorrectly sized for the out of spec headspace. </div></div>
a) The 1889 Mauser case head for the 7.65x53mm built with a large primer pocket is SAAMI registered for as much as 65kpsi in the 270, 6mmRem, and the 22-250 Rem.
I can load practical ammo for myself up to 67kpsi with my sitiuation.
But when the same case head is made with a small primer pocket, as in the 6mmBR, the primer pocket is stronger than the primer and pierced primers become the limit.
Many rifles pierce at ~ 85kpsi. Gre tan offers a firing pin bushing service and the bushed pins will go higher.
b) Primer pockets again. See above
c) yada yada
d) yada yada
f) yada yada
What it all means is that I can develop a load when a 223 can run 75kpsi forever and is registered at 55kpsi, my loads can be better the recipie books.
YAOG should stick with published loads and SAAMI registered pressures at this stage of his development.
1) yada yada
2) If I work up a load unil the brass fails, some guns blow up first, some don't.
I have tested hundred of guns this way.
It is very important catogorization.
3) yada yada
a)<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">If you are piercing primers more than likely there is a firearm problem frequently a poorly shaped firing pin, weak firing pin spring, out of spec headspace with handloads that are incorrectly sized for the out of spec headspace. </div></div>
a) The 1889 Mauser case head for the 7.65x53mm built with a large primer pocket is SAAMI registered for as much as 65kpsi in the 270, 6mmRem, and the 22-250 Rem.
I can load practical ammo for myself up to 67kpsi with my sitiuation.
But when the same case head is made with a small primer pocket, as in the 6mmBR, the primer pocket is stronger than the primer and pierced primers become the limit.
Many rifles pierce at ~ 85kpsi. Gre tan offers a firing pin bushing service and the bushed pins will go higher.
b) Primer pockets again. See above
c) yada yada
d) yada yada
f) yada yada
What it all means is that I can develop a load when a 223 can run 75kpsi forever and is registered at 55kpsi, my loads can be better the recipie books.
YAOG should stick with published loads and SAAMI registered pressures at this stage of his development.
Re: pressure test
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">1) yada yada
2) If I work up a load unil the brass fails, some guns blow up first, some don't.
I have tested hundred of guns this way.
It is very important catogorization.</div></div>
If you had used a strain gauge you might not have blown up all those guns. What is "very important" about catagorizing the guns you manage to blow up vs. the guns you did not manage blow up?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">3) yada yada</div></div>
Easy for you to say being a self proclaimed advanced reloader and all. I'm not an "advanced reloader" like you claim to be but in over 40 years of reloading I have somehow managed to avoid blowing up any guns at all. Is blowing up guns a requirement to becoming an advanced reloader?
a)<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">a)<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: YAOG</div><div class="ubbcode-body">If you are piercing primers more than likely there is a firearm problem frequently a poorly shaped firing pin, weak firing pin spring, out of spec headspace with handloads that are incorrectly sized for the out of spec headspace.</div></div>
The 1889 Mauser case head for the 7.65x53mm built with a large primer pocket is SAAMI registered for as much as 65kpsi in the 270, 6mmRem, and the 22-250 Rem.
I can load practical ammo for myself up to 67kpsi with my sitiuation.
But when the same case head is made with a small primer pocket, as in the 6mmBR, the primer pocket is stronger than the primer and pierced primers become the limit.
Many rifles pierce at ~ 85kpsi. Gre tan offers a firing pin bushing service and the bushed pins will go higher.
b) Primer pockets again. See above
c) yada yada
d) yada yada
f) yada yada
What it all means is that I can develop a load when a 223 can run 75kpsi forever and is registered at 55kpsi, my loads can be better the recipie books.</div></div>
O.K. whatever you say. The technical term "yada yada yada yada yada yada" is way to advanced for me not being an "advanced reloader" to understand.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">YAOG should stick with published loads and SAAMI registered pressures at this stage of his development.
</div></div>
I don't limit myself to published loads any more than you do but I do prefer to not blow up guns. What are registered pressures?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">1) yada yada
2) If I work up a load unil the brass fails, some guns blow up first, some don't.
I have tested hundred of guns this way.
It is very important catogorization.</div></div>
If you had used a strain gauge you might not have blown up all those guns. What is "very important" about catagorizing the guns you manage to blow up vs. the guns you did not manage blow up?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">3) yada yada</div></div>
Easy for you to say being a self proclaimed advanced reloader and all. I'm not an "advanced reloader" like you claim to be but in over 40 years of reloading I have somehow managed to avoid blowing up any guns at all. Is blowing up guns a requirement to becoming an advanced reloader?
a)<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">a)<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: YAOG</div><div class="ubbcode-body">If you are piercing primers more than likely there is a firearm problem frequently a poorly shaped firing pin, weak firing pin spring, out of spec headspace with handloads that are incorrectly sized for the out of spec headspace.</div></div>
The 1889 Mauser case head for the 7.65x53mm built with a large primer pocket is SAAMI registered for as much as 65kpsi in the 270, 6mmRem, and the 22-250 Rem.
I can load practical ammo for myself up to 67kpsi with my sitiuation.
But when the same case head is made with a small primer pocket, as in the 6mmBR, the primer pocket is stronger than the primer and pierced primers become the limit.
Many rifles pierce at ~ 85kpsi. Gre tan offers a firing pin bushing service and the bushed pins will go higher.
b) Primer pockets again. See above
c) yada yada
d) yada yada
f) yada yada
What it all means is that I can develop a load when a 223 can run 75kpsi forever and is registered at 55kpsi, my loads can be better the recipie books.</div></div>
O.K. whatever you say. The technical term "yada yada yada yada yada yada" is way to advanced for me not being an "advanced reloader" to understand.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">YAOG should stick with published loads and SAAMI registered pressures at this stage of his development.
</div></div>
I don't limit myself to published loads any more than you do but I do prefer to not blow up guns. What are registered pressures?
Re: pressure test
I have lots of CEA-O6-250UW-350 strain gauges, but no more patients for your straightening out your shaggy dog posts.
I have lots of CEA-O6-250UW-350 strain gauges, but no more patients for your straightening out your shaggy dog posts.
Re: pressure test
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">I have lots of CEA-O6-250UW-350 strain gauges, but no more patients for your straightening out your shaggy dog posts. </div></div>
Really? What did you use for data acquisition and what was your sample rate?
And more interestingly as a self-proclaimed "advanced reloader" how did you manage to blow up all those guns even using a strain gauge to monitor chamber pressures?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">I have lots of CEA-O6-250UW-350 strain gauges, but no more patients for your straightening out your shaggy dog posts. </div></div>
Really? What did you use for data acquisition and what was your sample rate?
And more interestingly as a self-proclaimed "advanced reloader" how did you manage to blow up all those guns even using a strain gauge to monitor chamber pressures?
