CBTO

[Muddyboots]

You know if you really think about this, its the perfect TROLL! Got us all twisting in the wind!

Its called a comparator:
noun:

1. Any of various instruments for comparing a measured property of an object, such as its shape, color, or brightness, with a standard.
2. An apparatus for making comparisons; especially, an instrument for comparing the lengths of nearly equal bars, either from end to end or between lines engraved upon them.

an organization, activity, etc. that is used to judge the performance of another similarorganization or activity.

From my perspective, its not an absolute measurement. It provides a reference for each loader based upon their own measurement ability.

 

[ntsqd]

Have him measure a loaded round with his tools, and he has his number. The tools (excepting SAC) aren't accurate enough to be more than comparators.

It wouldn't be the end of the world to have to do this since this is what's happening now, but imagine a world where when he does this his number(s) align with yours because there was a standard for these tools. Their accuracy and more importantly their consistency would increase. Sort of like how there is a standard for the calipers that you're using with these attachments. Put it differently, imagine the std. for those calipers didn't exist. Where would we be then? I think that this is a good idea, but I know how resistant to change people can be and even if I had the traction that I don't I wouldn't try to push it thru.

 

[Muddyboots]

Tool deflection major part of discrepancies.

 

[QuietTexan]

but imagine a world where when he does this his number(s) align with yours because there was a standard for these tools.

It does exist, go pay for a SAC kit. $175 versus $30 for the Hornady.

 

[Mike6158]

I like the SAC comparators.

 

[QuietTexan]

I like the SAC comparators.

Me too. My caliber inserts are all within 0.0005" of each other, most are the exact same.

 

[ntsqd]

It does exist, go pay for a SAC kit. $175 versus $30 for the Hornady.

Me too. My caliber inserts are all within 0.0005" of each other, most are the exact same.

That's not a standard. That is one company doing a good job. If it were a standard then the other mfg's tools would also yield numbers within that tolerance range. It's clear to me continuing with this is pointless.

 

[lancetkenyon]

well, i'll catch HE77 from many especially from ALL the doodad makers who make tools to measure these lengths. I think .20 thou is the thickness of a piece of paper. Not an engineer
I'm old and have been reloading forever. I too went through the OCD era of my reloading. IT's all pretty much BS. Your rifle will shoot or it won't, PERIOD. People continue to buy 1 MOA rifles and try to get them to shoot .25MOA. STOP!!! You're chasing unicorns. Hunters should load for FUNCTION, NOT gnat hair accuracy.
For those who continue to unethically shoot game at stupid ranges only to hit them (if at all) in the ***, only for the animal to get away and die a cruel death being eaten alive by predators.

OPPS got off track. Do what you want, but, seat to functioning magazine length, leave the minutia to the benchrest folk.

I will disagree with not needing gnat hair accuracy in a hunting rifle. I will take my .2MOA accuracy all day long. I am meticulous to get that kind of accuracy. They feed great, and the function of the 105 Hyb cannot be disputed.

A 1MOA rifle might be fine for deer or elk at 440 yards. Not so much for pest eradication.

441 yards yesterday. Prairie dog head shot. 1st round hit.

Chupacabra @ 40 yards. Dumped it too.

 

[Mike6158]

Man, I don't know how to break this to you but your pet Prairie Dog is going to need surgery. Probably more than one. The recovery path will be steep. There will be setbacks. But I think it'll be fine once rehab is behind it.

Dr. Mike (not a doctor)

 

[Muddyboots]

Killer migraine for sure!!!

 

[Mike D Texas]

It does exist, go pay for a SAC kit. $175 versus $30 for the Hornady.

I recently made this upgrade (Hornady to SAC). There is night and day difference in quality.

 

[RockyMtnMT]

It wouldn't be the end of the world to have to do this since this is what's happening now, but imagine a world where when he does this his number(s) align with yours because there was a standard for these tools. Their accuracy and more importantly their consistency would increase. Sort of like how there is a standard for the calipers that you're using with these attachments. Put it differently, imagine the std. for those calipers didn't exist. Where would we be then? I think that this is a good idea, but I know how resistant to change people can be and even if I had the traction that I don't I wouldn't try to push it thru.

The only way this could work is if there is no tolerance. There is a tolerance of a few ten thou in custom barrels. We hold a tolerance of 2 ten thou on Hammer Bullets. I can only imagine how big the tolerance is from one ogive measuring device to the next is. Even in the same name brand. Heck our $250 micrometers all measure slightly different. Each machine has it's own. There simply cannot be a standard for this that will make numbers match for everyone. Sliding a donut onto a radius ogive will show large differences in length with very small differences in diameter. The difference registered in length by this method will be much greater than it is actually.

Seat your bullet long. Put it in the chamber to see how far you are from being able to close the bolt. Keep seating it deeper until you can close the bolt and it barely leaves land marks on the bullet. Then seat it deeper the amount you want it off the lands for your starting longest oal. Set your seating die to it. Develop your load and adjust seating depth with the seating die until you find the oal that works best for you. Make a dummy round at this oal. Use that dummy round to set up the seating die on what ever press or set of dies. Stop measuring! It will make you crazy!

I started the thread just because we get requests on a regular basis for BTO measurement for a cartridge oal or bullet oal for someone doing load development or building a rifle. It just doesn't work that way. Just think how much money they have generated with this little tool and the rabbit hole it sends everyone down!

If you want to know how much throat to give a rifle, make a dummy round to the oal that you want. Give it to the smith and let him throat to it. This will turn out much better.

 

[Old Rooster]

I guess perfection is a bit more than elusive,it's downright impossible but I can see with my own eyes I can do better than my Hornady Comparator set.I will upgrade soon.
Not sure I can match Lance Kenyon's shooting and many other's here but I can boost my confidence in myself and my reloads.
Thanks to all that contributed to this thread as I have learned a lot!

 

[ntsqd]

The only way this could work is if there is no tolerance. There is a tolerance of a few ten thou in custom barrels. We hold a tolerance of 2 ten thou on Hammer Bullets. I can only imagine how big the tolerance is from one ogive measuring device to the next is. Even in the same name brand. Heck our $250 micrometers all measure slightly different. Each machine has it's own. There simply cannot be a standard for this that will make numbers match for everyone. Sliding a donut onto a radius ogive will show large differences in length with very small differences in diameter. The difference registered in length by this method will be much greater than it is actually.

Seat your bullet long. Put it in the chamber to see how far you are from being able to close the bolt. Keep seating it deeper until you can close the bolt and it barely leaves land marks on the bullet. Then seat it deeper the amount you want it off the lands for your starting longest oal. Set your seating die to it. Develop your load and adjust seating depth with the seating die until you find the oal that works best for you. Make a dummy round at this oal. Use that dummy round to set up the seating die on what ever press or set of dies. Stop measuring! It will make you crazy!

I started the thread just because we get requests on a regular basis for BTO measurement for a cartridge oal or bullet oal for someone doing load development or building a rifle. It just doesn't work that way. Just think how much money they have generated with this little tool and the rabbit hole it sends everyone down!

If you want to know how much throat to give a rifle, make a dummy round to the oal that you want. Give it to the smith and let him throat to it. This will turn out much better.

The way that I see it such a std. would need to be designed to reduce that to an acceptable amount with realistic tolerances for the gauging parts. It is not impossible, it's just a question of what is acceptable and what is reasonable to manufacture.
BUT there are enough here who are fighting the mere mention of a possibly better way to share info that I simply don't care any more.