Hornady OAL gauge varies with bullets?
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Re: Hornady OAL gauge varies with bullets?
IF you mean Over All Length, it is what it is, head to meplat, no matter the bullet.
IF you mean the head to ogive length, we're measuring the jump to the rifling. For that, the OAL will certainly vary with different bullet designs to maintain the same jump.
IF you mean Over All Length, it is what it is, head to meplat, no matter the bullet.
IF you mean the head to ogive length, we're measuring the jump to the rifling. For that, the OAL will certainly vary with different bullet designs to maintain the same jump.
Re: Hornady OAL gauge varies with bullets?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: thefitter</div><div class="ubbcode-body">It seems that the measurement is different depending on the bullet type and even weight.
There is a difference between SMK in 168 or 175. I'm surprised.
</div></div>
Wait until you measure different lots of the same bullet, or put the tool into your action oriented one way vs. the another, the time before.
There is a learning curve and a certain finesse' which is required with the Hornady/Stoney Point OAL gage.
For the straight tool, I insert it into the action, using a single bullet with the thumbscrew at the 12:00 position, making sure I have a good seating of the bullet. I'll write this number down.
I'll then take the same bullet and put the thumbscrew at the 3:00 position, relative to the action's top, measure and write this number down.
Finally, I'll put the thumbscrew at the 9:00 position and measure with that same bullet, write it down and then average these three measurements together.
This is the OAL for bullet #1.
Depending on time, I'll grab two more bullets (total of 3) and repeat the above process (or I'll do 4 more) and average those 3, or 5 numbers together for a final OAL for that lot of bullets.
Number these 3, or 5, bullets and place them in a ziplock baggie, along with a sheet of paper with the each's averaged OAL and use them to tell you how much throat errosion you have, if you're starting out with a new barrel, as you progress through your round-count.
This is the process I use for each and every specific bullet type/lot number.
I have three distinct Hornady 7mm 162gr HPBT Nation Match bullets, all with the same part number, but their design and dimensions are all over the map.
Same with some 168gr 7mm SMKs.
Chris
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: thefitter</div><div class="ubbcode-body">It seems that the measurement is different depending on the bullet type and even weight.
There is a difference between SMK in 168 or 175. I'm surprised.
</div></div>
Wait until you measure different lots of the same bullet, or put the tool into your action oriented one way vs. the another, the time before.
There is a learning curve and a certain finesse' which is required with the Hornady/Stoney Point OAL gage.
For the straight tool, I insert it into the action, using a single bullet with the thumbscrew at the 12:00 position, making sure I have a good seating of the bullet. I'll write this number down.
I'll then take the same bullet and put the thumbscrew at the 3:00 position, relative to the action's top, measure and write this number down.
Finally, I'll put the thumbscrew at the 9:00 position and measure with that same bullet, write it down and then average these three measurements together.
This is the OAL for bullet #1.
Depending on time, I'll grab two more bullets (total of 3) and repeat the above process (or I'll do 4 more) and average those 3, or 5 numbers together for a final OAL for that lot of bullets.
Number these 3, or 5, bullets and place them in a ziplock baggie, along with a sheet of paper with the each's averaged OAL and use them to tell you how much throat errosion you have, if you're starting out with a new barrel, as you progress through your round-count.
This is the process I use for each and every specific bullet type/lot number.
I have three distinct Hornady 7mm 162gr HPBT Nation Match bullets, all with the same part number, but their design and dimensions are all over the map.
Same with some 168gr 7mm SMKs.
Chris
Re: Hornady OAL gauge varies with bullets?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: ChrisGarrett</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: thefitter</div><div class="ubbcode-body">It seems that the measurement is different depending on the bullet type and even weight.
There is a difference between SMK in 168 or 175. I'm surprised.
</div></div>
Wait until you measure different lots of the same bullet, or put the tool into your action oriented one way vs. the another, the time before.
<span style="color: #3366FF">You just had to say this didn't you?</span>
There is a learning curve and a certain finesse' which is required with the Hornady/Stoney Point OAL gage.
For the straight tool, I insert it into the action, using a single bullet with the thumbscrew at the 12:00 position, making sure I have a good seating of the bullet. I'll write this number down.
I'll then take the same bullet and put the thumbscrew at the 3:00 position, relative to the action's top, measure and write this number down.
Finally, I'll put the thumbscrew at the 9:00 position and measure with that same bullet, write it down and then average these three measurements together.
This is the OAL for bullet #1.
Depending on time, I'll grab two more bullets (total of 3) and repeat the above process (or I'll do 4 more) and average those 3, or 5 numbers together for a final OAL for that lot of bullets.
Number these 3, or 5, bullets and place them in a ziplock baggie, along with a sheet of paper with the each's averaged OAL and use them to tell you how much throat errosion you have, if you're starting out with a new barrel, as you progress through your round-count.
This is the process I use for each and every specific bullet type/lot number.
I have three distinct Hornady 7mm 162gr HPBT Nation Match bullets, all with the same part number, but their design and dimensions are all over the map.
Same with some 168gr 7mm SMKs.
Chris </div></div>
I took 6 measurements and then averaged them. The biggest variable I see is how much pressure is applied when advancing the rod.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: ChrisGarrett</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: thefitter</div><div class="ubbcode-body">It seems that the measurement is different depending on the bullet type and even weight.
There is a difference between SMK in 168 or 175. I'm surprised.
</div></div>
Wait until you measure different lots of the same bullet, or put the tool into your action oriented one way vs. the another, the time before.
<span style="color: #3366FF">You just had to say this didn't you?</span>
There is a learning curve and a certain finesse' which is required with the Hornady/Stoney Point OAL gage.
For the straight tool, I insert it into the action, using a single bullet with the thumbscrew at the 12:00 position, making sure I have a good seating of the bullet. I'll write this number down.
I'll then take the same bullet and put the thumbscrew at the 3:00 position, relative to the action's top, measure and write this number down.
Finally, I'll put the thumbscrew at the 9:00 position and measure with that same bullet, write it down and then average these three measurements together.
This is the OAL for bullet #1.
Depending on time, I'll grab two more bullets (total of 3) and repeat the above process (or I'll do 4 more) and average those 3, or 5 numbers together for a final OAL for that lot of bullets.
Number these 3, or 5, bullets and place them in a ziplock baggie, along with a sheet of paper with the each's averaged OAL and use them to tell you how much throat errosion you have, if you're starting out with a new barrel, as you progress through your round-count.
This is the process I use for each and every specific bullet type/lot number.
I have three distinct Hornady 7mm 162gr HPBT Nation Match bullets, all with the same part number, but their design and dimensions are all over the map.
Same with some 168gr 7mm SMKs.
Chris </div></div>
I took 6 measurements and then averaged them. The biggest variable I see is how much pressure is applied when advancing the rod.
Re: Hornady OAL gauge varies with bullets?
The COAL tool actually measures the length of a particular round from base of case to where the ogive contacts the rifling. You have to then measure that round with a bullet comparator on your calipers to get the real masurement as the reading will vary from bullet to bullet if measured from case base to bullet tip.
Almost all bullets will vary in the slope of the ogive and thus the COAL to touch the rifling.
The 168 grain and 175 grain SMK's have a different shape and length so the COAL is different for each.
Read the advice on how to use the COAL tool that is given on www.6mmbr.com
It will improve your consistency, and that is what you are after, consistency.
tater
The COAL tool actually measures the length of a particular round from base of case to where the ogive contacts the rifling. You have to then measure that round with a bullet comparator on your calipers to get the real masurement as the reading will vary from bullet to bullet if measured from case base to bullet tip.
Almost all bullets will vary in the slope of the ogive and thus the COAL to touch the rifling.
The 168 grain and 175 grain SMK's have a different shape and length so the COAL is different for each.
Read the advice on how to use the COAL tool that is given on www.6mmbr.com
It will improve your consistency, and that is what you are after, consistency.
tater
Re: Hornady OAL gauge varies with bullets?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: tater</div><div class="ubbcode-body">The COAL tool actually measures the length of a particular round from base of case to where the ogive contacts the rifling. You have to then measure that round with a bullet comparator on your calipers to get the real masurement as the reading will vary from bullet to bullet if measured from case base to bullet tip.
Almost all bullets will vary in the slope of the ogive and thus the COAL to touch the rifling.
The 168 grain and 175 grain SMK's have a different shape and length so the COAL is different for each.
Read the advice on how to use the COAL tool that is given on www.6mmbr.com
It will improve your consistency, and that is what you are after, consistency.
tater </div></div>
Remember the 'comparator' inserts are a single diameter and this chosen diameter may, or may not, coincide with the diameter of where the lands begin and the leade ends, in any given rifle. They're not custom made jobbies.
Also, those modified cases are generically sized and can be all over the map, relative to a specific rifle's chamber and this can affect the final measurements, either at the ogive, or the tip.
I hate to be a stick-in-the-mud about it, but although we try and deal with very minute measurements, we're really at the mercy of tolerances and well...bullets, bores and tools are all man-made objects and far from perfect.
You take a small sample size, get an 'average' and go from there, is my thought on it.
Chris
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: tater</div><div class="ubbcode-body">The COAL tool actually measures the length of a particular round from base of case to where the ogive contacts the rifling. You have to then measure that round with a bullet comparator on your calipers to get the real masurement as the reading will vary from bullet to bullet if measured from case base to bullet tip.
Almost all bullets will vary in the slope of the ogive and thus the COAL to touch the rifling.
The 168 grain and 175 grain SMK's have a different shape and length so the COAL is different for each.
Read the advice on how to use the COAL tool that is given on www.6mmbr.com
It will improve your consistency, and that is what you are after, consistency.
tater </div></div>
Remember the 'comparator' inserts are a single diameter and this chosen diameter may, or may not, coincide with the diameter of where the lands begin and the leade ends, in any given rifle. They're not custom made jobbies.
Also, those modified cases are generically sized and can be all over the map, relative to a specific rifle's chamber and this can affect the final measurements, either at the ogive, or the tip.
I hate to be a stick-in-the-mud about it, but although we try and deal with very minute measurements, we're really at the mercy of tolerances and well...bullets, bores and tools are all man-made objects and far from perfect.
You take a small sample size, get an 'average' and go from there, is my thought on it.
Chris
Re: Hornady OAL gauge varies with bullets?
You take a small sample size, get an 'average' and go from there, is my thought on it.
you forgot to add...AND HOPE FOR THE BEST
You take a small sample size, get an 'average' and go from there, is my thought on it.
you forgot to add...AND HOPE FOR THE BEST
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