Improved results with calipers? Tricks?

[gifbohane]

Do any of you have an specific techniques that you found or use to improve your ability to measure carts and bullets?

That is besides practice, repetitive motions and care...

 

[LiveLife]

Use of pin gages to verify accuracy of your calipers.

I initially practiced with eyes closed but realized my calipers were just worn . Of course, if you force the calipers, you COULD influence the readings and why practicing with known standard like pin gages will give you more consistent readings and "feel" as to how much pressure to use.

I retired my dial calipers I bought when I started reloading when it was too worn to consistently read to .001" as verified by pin gages.

My new Frankford Arsenal dial calipers and 10 year old Harbor Freight digital calipers (Many report new ones are not as good) are "tight" and consistently verify pin gages to .001" without looseness and read consistent with my Brown and Sharpe micrometer.

BTW, pin gages are quite affordable as they are around $2 - $4 - https://www.thehighroad.org/index.p...ks-for-digital-calibers.821135/#post-10545265

 

[mdi]

It sometime takes a while to develop a "feel" for using precision measuring tools. Only a light touch is needed when closing the jaws of a caliper. For reloading my dial calipers are used for measuring OAL 98% of the time and for measuring diameters I use a micrometer. For rough, quickie diameter measurements I may use my calipers, but again, a light touch making sure the jaws flat portion is square on the object being measured. I don't care for digital calipers (tried 2 that eventually died an early death) and during my careers as a machinist/mechanic I have used/needed only two dial calipers. The will last a very long time if not abused. Here's a good video of using a dial caliper;

 

[PWC]

A micrometer seems to need a third hand sometimes, so I bought a small vice and placed my micrometer in it; that allows one hand to hold the piece and one hand to adjust the mic.

Calipers is just practice and check ref periodically.

 

[whughett]

I hear you. Seems I have to fiddle sometimes, I use the knife edges on round surfaces like bullets and the flats in case mouths or bullet tips. I also have two sets, one digital and cross reference them to each.

The “pin gages” sound like a good investment for someone doing precision work.

 

[deadeye dick]

I use a known good mike to check my calipers

 

[12Bravo20]

I have several check gages that came with my micrometers that I use to check my dial and digital calipers.

 

[jmorris]

Standards are the best way to learn, if you are getting incorrect or different measurements using them, it’s either you or the equipment because they are staying the same size.

Micrometers are the tool you want for the best accuracy and can be had with ratchet or friction stops that are good for folks that seem to think they are clamps vs precision measuring instruments. Most inconsistent use of calipers is due to excessive force too.

 

[Varminterror]

The most important trick I can recommend is to avoid using calipers where they aren’t the appropriate tool.

Second most important trick I can offer is to avoid being hung up on irrelevant measurements. COAL, as an example, is a near-meaningless metric for a rifle cartridge reloader, but it seems to be the major focus for most folks.

 

[skeeterfogger]

I don't reload but when I'm doing somthing I want to be precise with I utilize 2 or more measurement devices. Its a bit of hassle but if all are good devices one should get identical measurements between them even including very minute differences being in specs. The advantage, to me, is even if something seems off it tends to only be a matter of one became out of zero. But at least it sets a president to be consistant with tolerances. Might slow the progress a bit but fast not always good.

 

[Varminterror]

I don't reload but when I'm doing somthing I want to be precise with I utilize 2 or more measurement devices.

One device with ability to calibrate/confirm is far more valuable than two devices.

“A man with one watch knows the time, a man with two is never sure.” But in reality, the man with two watches has reason to doubt both watches, and the man with one is blissfully ignorant to the inaccuracy of his single device. Rather, the true solution is the ability to confirm the watch, the device, against a known standard.

As an example of this fallacy in reloading practices: many reloaders will “check” their electronic powder dispenser by also massing (not weighing) the charges on a balance beam. In reality, when you get down to real analytics, most of these beams have no greater reliability, accuracy, nor precision than an electronic dispenser/scale. Temperature, lube or lack thereof, dust or lack thereof, a slightly different influence when the pan or charge is placed (velocity vs. stiction), humidity, even electromagnetic fields, etc can all influence a beam balance. In some cases, the beam has LESS precision and accuracy than an electronic scale. Let alone talking about linearity of the beam!!

So overall, in most cases, having two sets of calipers, or “confirming” dispensed charge weights on a beam scale is a false confidence.

One quality device with a means to calibrate against a known standard is the trick, having two devices with inherent inaccuracies is not.

 

[PWC]

Second most important trick I can offer is to avoid being hung up on irrelevant measurements. COAL, as an example, is a near-meaningless metric for a rifle cartridge reloader, but it seems to be the major focus for most folks.

Well, I agree and got banned from another shooting site for saying so, because they thought it might be dangerous. More important is where ogive meets rifling.

 

[Walkalong]

One device with ability to calibrate/confirm is far more valuable than two devices.

Agreed. Also agree with using a micrometer when better measurements are needed.

 

[Walkalong]

Take this particular digital caliper. It's dead on with this .308 pin gauge, but it reads .001 short on smaller pin gauges.
The moral of this story is you need to check your calipers in the size area(s) you are trying to measure.

My Mitutoyo digital caliper is pretty much dead on with my pin gauges from to .061 to .500. They also do very well with my Gauge Block set as well.

The pin gauges and block set are handy for checking calipers in the size range you are measuring in, but you are still better served with a micrometer if you need the correct nearest .001 or better.

For most reloading measurements we need consistency more than we need the exact .001, so cheap calipers work for that.

But let's say we have a tight necked .262 neck chamber we are loading for Benchrest and our loaded rounds need to have .001 clearance
all around in the neck area, then we need a micrometer to be sure. I have seen digital calipers that are off .002, that would get you in big trouble.

 

[ATLDave]

COAL, as an example, is a near-meaningless metric for a rifle cartridge reloader, but it seems to be the major focus for most folks.

There are a lot of things in shooting where there is some tension between that which is easy to (repeatably) measure and that which is most directly meaningful to measure. This comes up over and over again. Sometimes it's just too hard to directly measure the "real" thing or the important thing - and you end up measuring something else as a proxy, just because it's easier to measure. That's often a good strategy, but it needs to be done with consciousness of the tradeoffs involved.

 

[gifbohane]

You guys took this beyond where I wanted to go but, as usual, thanks for the info.

Varmint -would you care to elaborate on why COL is not relevant? Do you think that this is true for straight wall cases also?

 

[Walkalong]

would you care to elaborate on why COL is not relevant?

For accuracy loads in rifle calibers you want base to ogive. OAL is meaningless other than for fit in the magazine. Stack up even some match bullets and see how much they can vary in length. The ogive is what hits the lands, and we want to know that and be consistent with it.

 

[gifbohane]

Sometimes I get shocked at the amount of information that I do not know......

 

[whughett]

In black powder loaded cartridges you better pay attention to OAL or you could blow something.
And in conversion cylinders for cap revolvers it’s either seat a bullet to a specific length or risk jamming the cylinder rotation against the barrel.

Either way I use a caliper to determine these factors.

 

[mdi]

Yep gifbohane, quite often on reloading forums a simple question is asked and answers start simple but morph into advanced reloading methods, physics and theory...

 

[GT1]

Calipers while a precision measurement tool, are not all that. They are quick check tools. If you want precise you use a micrometer. Regardless it takes a bit of practice to be consistent and develop a feel for what you are doing with these tools.

 

[Rule3]

Yep gifbohane, quite often on reloading forums a simple question is asked and answers start simple but morph into advanced reloading methods, physics and theory...

Very true. In most discussions the vlue of Pi, 3.14 is good enough but for reloading a 9mm to shoot at the range it would be
3.14159

 

[Varminterror]

Varmint -would you care to elaborate on why COL is not relevant?

This v

For accuracy loads in rifle calibers you want base to ogive. OAL is meaningless other than for fit in the magazine. Stack up even some match bullets and see how much they can vary in length. The ogive is what hits the lands, and we want to know that and be consistent with it.

Do you think that this is true for straight wall cases also?

It’s true for anything which is feeding into a leade. Even Black Powder cartridges. COAL is really only important for fitting into feeding mechanisms, either mag boxes, carriers, or cylinders, and in that, isn’t a high precision measurement, it’s simply a maximum length - if it fits, it ships. For any other use, and anything being measured down to the thousandths place, COAL isn’t a relevant or appropriate measure. It’s easy, sure. But it’s not appropriate. Guys get away with it because they use long jumps which forgive bullet ogive variability - measuring and recording down to the thousandth, then making a macro move back 20-30 thousandths.

To be honest, I didn’t even measure my COAL for my rounds in my PRS match rifle last season. I used the bolt lift method to determine my kiss depth, pushed it down 5 thou on the micrometer head, checked that it fit in my mags, and loaded test rounds. Burned out my barrel without ever measuring COAL, or even BTO, shot .1-.4moa on day one, still shooting .3-.7moa when I took off the barrel.

 

[Varminterror]

There are a lot of things in shooting where there is some tension between that which is easy to (repeatably) measure and that which is most directly meaningful to measure. This comes up over and over again. Sometimes it's just too hard to directly measure the "real" thing or the important thing - and you end up measuring something else as a proxy, just because it's easier to measure. That's often a good strategy, but it needs to be done with consciousness of the tradeoffs involved.

It’s no easier to measure COAL than BTO. Just costs $20 more.

 

[ATLDave]

It’s no easier to measure COAL than BTO. Just costs $20 more.

Most measuring tasks can be made easier if you throw money at them!