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50/50
02-09-2014, 09:39 PM
Does anyone use micrometers or do most (like me) just use calipers. I've got a micrometer that was given to me, but I never use it. I've been reloading for years and I have yet to find a need for a micrometer. What will it do that a caliper won't. Am I missing something here?

Thanks

Ickisrulz
02-09-2014, 09:43 PM
It is a matter of accuracy for our needs. Micrometers are used to measure the diameter of bullets. Calipers are used to measure case length.

country gent
02-09-2014, 09:54 PM
Michrometers are more accurate than most calipers, also if they have the vernieer on them will read one place finer .0001 compared to .001. Mikes are easier to handle once you learn to use them. Calipers have come along ways in accuracy in my time in the trade ( Tool Maker). Most read to .0005 now but alot dont trust the last place. I have a set of mics here I originally used for gage making that read to .00005. Both are delicate tools that need to be handled gently. Both need to be checked for calibration when being used. A trick to calipers is to check at or close to the desired measurement. IE if measuring 2" check with a 2" gage block or standard rather than running down to 0. Make sure jaws are clean and burr free. Peridically check through out the range at every inch.

MtGun44
02-11-2014, 12:25 AM
For boolit diameters, the .0001 micrometer is required. Pretending that the calipers
are actually accurate to tighter than .001 is a fun game, but not connected to reality.
READING the instrument to more accuracy than it can deliver is a silly waste of time,
although some claim "I can read it to . . . . . ." whatever.

Enco Tool sells Fowler .0001 reading mics for typically at or under $35 most of the time.
Used Brown & Sharpe, Starrett or Mitutoyo mics on eBay can be good deal. Make sure
it has the last digit vernier to get to .0001

Bill

milrifle
02-11-2014, 08:38 AM
I am sometimes amused at folks who degrade calipers. Perhaps some are as inaccurate as their reputation, but both of mine have read dead on when compared to my mic on the occasions I've compared the readings. I admit, they are not for reading .0001 accuracy, but if all you need is .001, mine are just fine. I've seen some folks tell you that they vary +/- .002 or more. I've just not seen that with mine. Even for measuring bullets, I figure a reading to the closest .001 is close enough for me. Since I try to oversize by .001 to .002., I'm not real concerned whether that is .0009 or .0011, so long as it's over and not way over. Maybe it makes more difference to those that are better shots than me.

alamogunr
02-11-2014, 08:48 AM
For boolit diameters, the .0001 micrometer is required. Pretending that the calipers
are actually accurate to tighter than .001 is a fun game, but not connected to reality.
READING the instrument to more accuracy than it can deliver is a silly waste of time,
although some claim "I can read it to . . . . . ." whatever.

Enco Tool sells Fowler .0001 reading mics for typically at or under $35 most of the time.
Used Brown & Sharpe, Starrett or Mitutoyo mics on eBay can be good deal. Make sure
it has the last digit vernier to get to .0001

Bill

I remember in college(BC-Before Calculators) we always swaged the last digit when using a slide rule. Not sure why since professors really didn't care about that. I guess it made us feel like we were being real engineers.

kaskillo
02-18-2014, 12:00 AM
I use my Mitutoyo digital Caliper for 95% of my brass processing with great results.

http://i1010.photobucket.com/albums/af226/kaskillo223/Brass%20bulk%20and%20equipment/858FE047-16AE-4B7C-8AFB-2E18C15BD3DA_zpsgnzrhs6t.jpg (http://s1010.photobucket.com/user/kaskillo223/media/Brass%20bulk%20and%20equipment/858FE047-16AE-4B7C-8AFB-2E18C15BD3DA_zpsgnzrhs6t.jpg.html)

MtGun44
02-18-2014, 12:57 AM
Calipers are the perfect tool for brass measurement.

Bill

ROGER4314
02-18-2014, 02:08 AM
Regardless of the instrument accuracy, operator "feel" is the key to proper operation. I taught use of calipers and micrometers for years and can assure you that a poorly trained operator can screw up even the finest instrument! They are LESS apt to mess up a measurement using a dial caliper.

Flash

milrifle
02-18-2014, 08:35 AM
This is a little off topic, but I once had a guy tell me he went over to a friend's house where he was building a model airplane. The guy was using some 0-1 mics for C-Clamps! Seems his father-in-law had passed away and left him his tools. Bet that guy is spinning in his grave faster than that airplane's prop.

bullet maker 57
02-18-2014, 12:40 PM
I use calipers for brass work and a micrometer when making bullets.

N4AUD
02-18-2014, 12:47 PM
I own both, use both and as others have said, calipers are great for measuring things such as case length, micrometers are best for boolit and bullet diameters. Don't use el cheapo models, get good brand names. I got mine used on Ebay, both like new at very low prices.

country gent
02-18-2014, 12:54 PM
The biggest thing with precisson measuring is "learning" the feel of the tool and what that feels like. Without that touch/feel accuracy is out the window. I worked 35 years as tool maker gagemaker and measuring was always an issue on the floor. Gage and layout had CMMs that didnt require that feel. They also had a controlled enviroment of temperature and humidity. Heat affects measurements also. I use Mics way more than calipers ( vernier, dial or digitals). The first thing that you need to do when measuring is wipe faces and check zero on the insterment. On close work I checked with gage blocks or pins at the dimension also, IE a swaging bullets of 308 dia I would check 0-1s with a 308 gage pin. That way I know 308 is 308 not 3077 or 3083. One of the things you learn with years of experience.

Love Life
02-18-2014, 11:04 PM
I use the micrometer for many things. Especially for setting my taper crimp on my auto pistol calibers.

Calipers get used for measuring brass length, with the comparator, etc.

BD
02-20-2014, 08:04 PM
I use dial calipers for most of my everyday reloading processes to insure that I stay with the acceptable "range". But if I want to know the actual dimension of something I use a mic. I have three, including a blade mic and a ball mic. And I have a stand, which can make all the difference.
BD

stu1ritter
02-22-2014, 07:03 AM
I think it is test and verify to answer your question. If your calipers are accurate in the range you want to measure, they are fine. I've checked my three calipers against some pin gauges I bought for cylinder throat measurements and none of them were accurate within one thou. 1 Mitutoyo dial and 2 digital cheapies. Get out the olde ten thou mic and bingo, right on the money to .xxxx accuracy. Same as everyone else, I measure bullets and crimps with the micrometer and brass and OAL with the calipers.
Stu

6bg6ga
02-22-2014, 07:19 AM
A "Good" set of calipers will measure very accurately. As a former quality control person I was trained in the proper use of both and CAN obtain an accurated reading from either. A mic in the hands of a person who doesn't know how to properly use it doesn't account for an increased accuracy. Ever seen a person try to measure something with a mic and tighten the mic entirely too tight? Any tool is only as good as the person using it.

Lloyd Smale
02-22-2014, 07:36 AM
correct answer. either depend more on the operator then the differences between them.
A "Good" set of calipers will measure very accurately. As a former quality control person I was trained in the proper use of both and CAN obtain an accurated reading from either. A mic in the hands of a person who doesn't know how to properly use it doesn't account for an increased accuracy. Ever seen a person try to measure something with a mic and tighten the mic entirely too tight? Any tool is only as good as the person using it.

cuzinbruce
02-25-2014, 04:58 PM
I have both, mostly Brown & Sharpe. I often use a micrometer to gage case length, just set it at the length you are checking for and lock the spindle. Also for correct overall length. That is with a 1-2" or 2-3" mic.

Moonman
02-26-2014, 08:53 AM
Handloader's should have a caliper and a micrometer both if they are serious.

REMEMBER, these are PRECISION INSTRUMENTS and need to be treated as such.

A micrometer IS NOT A SUBSTITUTE for a C-CLAMP.

There are YouTube videos on how to PROPERLY READ A MICROMETER also.:wink:

mdi
02-26-2014, 12:33 PM
One major difficulty when using a caliper vs. a micrometer is the narrow jaws and the length of the jaws. Narrow jaws can flex, get canted and give misleading measurements. Also narrow jaws may not give enough measuring surface to get accurate measurements on slightly irregular surfaces, like some bullets. Micrometers have a solid anvils and spindles that will not flex and are wide enough to get a good "flat" measuring surface. For reloading the difference isn't much when an experienced user measures, but new users often get measurements waaaay of with calipers.

I am a lifelong machinist/mechanic and have made machine parts with a tolerance of + 0.000", -.0005" being the closest and many, many parts with a +-.001" tolerance. I have used an old Brown and Sharpe 1" mic with carbide tips for many years measuring to .0005"...

Bogone
02-26-2014, 10:08 PM
I'll throw my two cents in here. I own a cnc machine shop and have some measuring equipment. I recently did a job for Uncle Sam that had such wide tolerances that you could use a tape measure. The job was source inspected so Uncle Sam sent a nice fella out to inspect the parts we were machining to size. The od on the part was plus or minus .030, the id was plus or minus .030, the thickness was plus or minus .060. Easy job for the old trusty digital calipers right? We'll yes and no, we could use the trusty calipers as long as we had traceable gauge blocks to check the calipers before, during and after the measurement. See a pattern here? We have made titanium valves for internal combustion engines that have crazy tolerances on the stem +.0000 -.0002 it is difficult to even measure without specialized equipment. I won' bore you with concentricity and other measuring issues. When I measure things I always check the measuring device against a known gage.

Kilroy08
02-26-2014, 10:22 PM
Have both in your tool box. If I have to get more nit picky than +/- .003, then I'll get out my micrometers.

Starrett, Brown & Sharpe, Lufkin, Mitutoyo, and Federal are all good brands to look out for. I've bought quite a few of my tools off eBay, just make sure it looks in decent shape in the pictures.

Also, check your local flea markets and antique shops. You never know what you'll find.

enfieldphile
02-27-2014, 12:26 AM
I was wondering why that C-CLAMP had all the funny numbers on it! :kidding:

Agreed! A Handloader should have both a caliper and a micrometer. A tubing mike is also in the cards once the Handloader delves a bit deeper. Things are easier today. With more choices, prices are a bit more competitive then back in the day. Learning to read them is easy. Developing "feel" for precision instruments and tools bit more involved. It's like playing a musical instrument. Some guys make the notes, other guys make the music!


Handloader's should have a caliper and a micrometer both if they are serious.

REMEMBER, these are PRECISION INSTRUMENTS and need to be treated as such.

A micrometer IS NOT A SUBSTITUTE for a C-CLAMP.

There are YouTube videos on how to PROPERLY READ A MICROMETER also.:wink:

Pinsnscrews
03-01-2014, 09:16 PM
I got very lucky, my brother in law was a former tool and die maker. When he moved, he left me his tool box. I have WAY more tools than I will need any time soon, but I have no problem calling him up and asking how to properly set up a tool. He walked me through reading a mic. I had no problem with .000, however, I was having a problem working it in my head for the last ten thousands. So I called him up, clicked on facetime, and had him walk me through it.

*click*
*click*
*click*
*click*
"wait, you tightened it too tight. Remember, only 3 clicks on the vernier and a very light touch. I want you to go One one-thousand CLICK two one-thousand CLICK three one-thousand click. If your getting your clicks faster than that, you turning it to hard."

Did I mention I really appreciate my brother in law?