caliper micrometer?

[chemist308]

If I'm going to cast, I need a caliper type micrometer, right? I'm going to slug my 9 mm and my 308 barrel. I've seen these micrometers vary greatly in price. What do you folks use/recommend?

[lwknight]

You need a micrometer with a wratchet on the thimble so you will always get the same pressure against the anvil. I found a RCBS with a digital side counter and it works/reads the same way as any standard mic too. It cost $54.00 at my local sporting goods.
I was thinking starret but no one had one locally and the RCBS seems pretty good.
I looked at a $24.00 mic at Northern Tool and decided that it was a cheapie so I passed it up.
I would guess you could expext to pay about 50 bucks for a real good mic.

[geargnasher]

Calipers and Micrometers are two different tools. You will need both. For a micrometer (C-clamp style with vernier marks on thimble and ratcheting stop) get a Brown & Sharpe, Fowler, or Starret and make sure it comes with calibration gauges. For the less precise but infinitly more versatile 0-6" calipers, I've found that a cheapo $30 pair is good enough for measuring case length and OAL.

Just don't try to measure your barrel slugs with a set of Chinese calipers and think you're doing any good.

Hope this helps,

Gear

[stephen perry]

Good Pawn Shop specializing in precision tools will have all the major brands of calipers and mics. Get youself a MCS catalogue or equivalent so you know new prices. Good name brand -Fowler, Mitutoyo, Starrett- mic in a Pawn Shop should go $50. I bought one of each for that price. A Craftsman .001 probably go for $25 and worth every penny. If you can't find a caliper under $50 go with a Chinese all the supply sellers sell the same one I bought my 2 new for $20 each some years back.

Stephen Perry
Angeles BR

[stephen perry]

gonne

[armyrat1970]

I am sure at some time you may need a good micrometer but all I use for my handloading needs is a 6" GRIP Caliper.

[bearmn56]

Chemist,
I worked as a Calibration Technician for 20 years....certifying the accuracy of a vast array of equipment. I have certified literally tens of thousands of micrometers of all types.
One has three choices for good caliper type micrometers. The dial caliper, the vernier caliper and the digital caliper. The dial caliper is the least desirable as in you drop it once and the dial is screwed up..... The vernier caliper is the most rugged...no fragile dial or electroics to get scrambled under rough usage. Most of these are accurate to +/- .001"...plenty good for general use.
Other choices...are thimble type micrometers....the ones that look vaguely like a C-clamp. Most of these are vernier types. However, there are some really good digital ones out now. The high grade precision micrometers are good to +/-.0001". The high grade ones are probably more accurate than necessary........+/- .001" being Ok for most stuff. However, that said, I have one of each type....I have a vernier caliper micrometer...an old Sears/Craftsman made in West Germany..good to +/- .001" that I use for most everything. I have several thimble micrometers...A Starret with the +/- .001 vernier and two Scher/Tumicos with the +/- .0001 vernier on the thimble. (Incidentally, the Tumico is an abbreviation for an excellent old company called the Tubular Micrometer Company).
For most people these days....I recommend one of the digital calipers with an LCD readout....They are accurate....will read in english and metric graduations...are reasonably rugged and don't require using a vernier. I am also a hobby machinist and have been using verniers...whether on my lathe, mill or caliper for years. Verniers require some study to be proficient in their use...........
So, get a good digital caliper....pay the extra...you won't be disappointed..
Bearmn56
Montana Territory

[hoosierlogger]

I have a cheap-o- Harbor freight $20 jobbie. It is accurate and the exact same as the RCBS one that they have at Gander Mountain for twice the price. The only thing different is the sticker with the name on it.

[deltaenterprizes]

Calipers and Micrometers are two different tools. You will need both. For a micrometer (C-clamp style with vernier marks on thimble and ratcheting stop) get a Brown & Sharpe, Fowler, or Starret and make sure it comes with calibration gauges. For the less precise but infinitly more versatile 0-6" calipers, I've found that a cheapo $30 pair is good enough for measuring case length and OAL.

Just don't try to measure your barrel slugs with a set of Chinese calipers and think you're doing any good.

Hope this helps,

Gear

Fowler is now Chinese,as is Starretts "value" line, Mitutoyo is excellent. That being said, I made it through machinist school and 2 years at my first job as a machinist using Chinese made tools. This is not NASA grade work we are doing where you need to measure .00005'', .001 is close enough. How many members have guage blocks to check the readings of their tools?
What was amazing was the accuracy of my Harbor Freight 6'' dial calipers that I paid $15 for, they were always within .001 of a reading using a micrometer.
Many tools today are the same Chinese tools as Harbor Freight with a different label, Sears, Home Depot, Lowes, Kurt(not the vises, the mics)to name a few. All the big corporations are doing it, that is why unemployment is so high. They take a brand name and use it to sell inferior quality tools to people that that don't know the difference. Look on the package for the place of manufacture.
The Chinese digital calipers eat batteries since the ON/OFF switch only turns off the LCD display, Mitutoyo digitals turn off the entire unit. There was gentleman that did a test and published it either on the Home Shop Machinist or Practical Machinist forum.
The Home Shop Machinist forum would be a great place for members to learn about machinist tooling and bullet casting and reloading are very related to the machinist trade, tool and die making being the acme of the trade.

[mpmarty]

I use a 6" digital caliper from Frankford Arsenal (sic) for case length and OAL measurements but for measuring barrel slugs and boolits I use my Brown and Sharp 0-1" micrometer. Both are necessary IMHO to do accurate casting / reloading. The caliper is self zeroing so it seems to be accurate enough for my needs. The B & S micrometer is checked for accuracy by measuring a set of reference diameter .223 match bullets that I selected years ago for concentricity and uniformity in diameter which just happens to be .2234

[theperfessor]

You might want to check out this thread:

http://www.castboolits.gunloads.com/showthread.php?t=67142

I posted some links there to a site I put up that includes instructions on how to read micrometers and vernier scales.

[mdi]

Over the years I have come to only use a Craftsman 6" DIAL caliper and a carbide tipped 0-1" Starrett (from many years ago), even though I have more tools. I just can't get used to some (random) numbers popping up in a display when I'm dealing with +/- .001" and sometimes less.

[Char-Gar]

The first precision measuring tool a handload needs is a high quality one inch Micrometer. I have four Starett one inch micromters. One has a ratchet, one has the friction thimble, one has neither and one is digital. Two read .001 and two read .0001. A micrometer that reads .001 is plenty good. It is not hard to split the difference with the eye and get a decent .0005 read. They all work just fine.

I don't see how a fellow could cast and load cast bullets without one.

I used a six in vernier caliper for years to measure cases and those rare instances when I wanted to measure something larger than one inch. My eyes don't like those fine vernier hash marks any more, so I gave it away and bought a new 6 inch electronic digital Starett. It is a good tool, but even the most expensive set of calipers won't replace a decent micrometer.

I am not a believer in cheap, make do tools. I have had my oldest Starett mic for over 50 years and it was well used when I got it. It is on the bench beside the lathe while I key this in. I just don't like Timex watches or throw away limited use measuring tools. When I buy, something I buy it for life.

[mooman76]

Lyman has a micrometer for around $30. It seems pretty good andwell built but I am no expert. I got my caliper from Harbor freight. They sel for about $25 for the digital ones. I have had it for about 6 years now with no problems.

[chemist308]

Thanks for the advice. I picked up a Lyman digital caliper--like this: Lyman Caliper (http://www.midwayusa.com/viewproduct/?productnumber=154410) but about $10 cheaper... So far i used it to check the thickness of what I cast and the interior diameter of my 9mm based off the widest points on interior of barrel, which bty is 0.355 in. With the ability to do that, do I even need to slug it?

[bearmn56]

Chemist,
Measuring the diameter of the bore at the muzzle is a great place to start. Yes, one can get a reasonably accurate measurement with a caliper. However, you are only measuring the bore/land dia at the muzzle. I usually slug my bores as well...especially with cast bullets. Slugging will tell you the tightest/smallest diameter of the bore. This is, of course, because the slug is pushed thru the bore and is squeezed down...to the tightest part of the barrel. By measuring the outside of the slug and comparing it to the measurement you took at the muzzle will give you a good crosscheck of your bore measurement at the muzzle. This will give you great practice in measuring the vagaries of bores and bullets!!!!:wink:
Hope this helps,
Bearmn56
Montana Territory

[JIMinPHX]

You should really slug it. Measuring that way gives you a slightly smaller reading than actual groove diameter size because of the flats on the caliper's measuring surfaces. You are not measuring the actual diameter, but rather the distance between two small chords on opposite sides of the circle.

Also, the accuracy of those digital jobs is sometimes not as good as they seem. They are usually specified accurate to somewhere between .0005 - .0015" maximum error. Some of them are good right out of the box. Some of them are a little off. It seems to be the luck of the draw if you get a good one or not. If you have a measurement standard like a jo-block that is close to the size you are measuring, then you can find out how accurate they really are in that area. Brand new drill bits are also a good item to use for a quick check & they are a little easier for the average Joe to find at his local hardware store. A brand new 5/16" drill bit should read .3125. A brand new 3.8" drill bit should read .3750. In addition to all this, slugging will allow you to get a measurement of an area further inside the barrel.

What you did is probably close enough for you to make some trial boolits though. You might try .356 or .357 diameter. Slugging should be more accurate, but what you have already is a whole lot better than nothing.

If you measure your boolits with the same calipers that you measure your barrel slugs with, then it doesn't really matter if the calipers are off a little or not. The same measuring error on both items will still give you boolits with a correct fit.

[TAWILDCATT]

I have most brands of mikes. and the chinese are as good as any.any of the tool companys are using chinese tools with their name on them. price does not mean quality.and reloaders dont need the most precise tools but good tools.if you want to pay high price for name brand that are also made in china go to it.

[AbitNutz]

Harbor freight has a sale going on through this weekend. I just bought a 6" digital caliper for $9.99. It is as accurate as Mitutoyo dial caliper and easier for me to read.

I was stunned at the quality of this thing for 10 bucks. The regular price is $30.00. I was stunned at that, let alone $10.00. Iit goes out to .000 which is all I need.

It even came with a spare battery and a pretty decent case.

[Green Frog]

Lyman markets surprisingly good stainless steel dial micrometers (not the plastic ones) and 1" micrometers that live in my shooting box. I have 3 sets of Starrett mics (0-5") and a couple of 'tuyo dial calipers and a 1" mic from them as well, but as a previous poster said, this ain't NASA here. I did use the Lyman stuff for a couple of machine shop courses at the local community college and was not at any significant disadvantage. JMHO, and of course YMMV! :)

Froggie

[stephen perry]

All good responses. You'll figure it out these guys did.

Stephen Perry
Angeles BR :brokenima

[geargnasher]

Fowler is now Chinese,as is Starretts "value" line, Mitutoyo is excellent. That being said, I made it through machinist school and 2 years at my first job as a machinist using Chinese made tools. This is not NASA grade work we are doing where you need to measure .00005'', .001 is close enough. How many members have guage blocks to check the readings of their tools?
What was amazing was the accuracy of my Harbor Freight 6'' dial calipers that I paid $15 for, they were always within .001 of a reading using a micrometer.
Many tools today are the same Chinese tools as Harbor Freight with a different label, Sears, Home Depot, Lowes, Kurt(not the vises, the mics)to name a few. All the big corporations are doing it, that is why unemployment is so high. They take a brand name and use it to sell inferior quality tools to people that that don't know the difference. Look on the package for the place of manufacture.
The Chinese digital calipers eat batteries since the ON/OFF switch only turns off the LCD display, Mitutoyo digitals turn off the entire unit. There was gentleman that did a test and published it either on the Home Shop Machinist or Practical Machinist forum.
The Home Shop Machinist forum would be a great place for members to learn about machinist tooling and bullet casting and reloading are very related to the machinist trade, tool and die making being the acme of the trade.

Delta, I was indicating that the average, uneducated person using a pair of Harbor Freight $20 digital calipers to measure barrel slugs for the purpose of selecting the right $28 sizer to get satisfactory boolit fit is likely to have a different kind of fit when they find they were .001" or more off in their measurements.

I often find that I have to make accurate fits in the +- .0002" arena to get satisfactory function and accuracy. For example, I have a Kimber .45 ACP which has a .4522 groove diameter (way oversize) and will accept and chamber a cartridge with a boolit of max .4531". A boolit .4534" will NOT chamber without force. A boolit .4528" and under leads the bore regardless of composition or velocity. Now if I was trying to accomplish this operation, including honing the sizing die, with an instrument capable of only .001" +- accuracy I would be in a pickle.

Reloading isn't rocket as you say, but it does require precision. Now I'm sure I'm going to get blasted by the "I just buy a Lee tumble lube mould, cast out of whatever lead-like stuff I have, and stuff it in the case without sizing" crowd, and I can't argue with them if it works, but one usually gets better results more quickly with precision.

Gear

[armyrat1970]

Delta, I was indicating that the average, uneducated person using a pair of Harbor Freight $20 digital calipers to measure barrel slugs for the purpose of selecting the right $28 sizer to get satisfactory boolit fit is likely to have a different kind of fit when they find they were .001" or more off in their measurements.

I often find that I have to make accurate fits in the +- .0002" arena to get satisfactory function and accuracy. For example, I have a Kimber .45 ACP which has a .4522 groove diameter (way oversize) and will accept and chamber a cartridge with a boolit of max .4531". A boolit .4534" will NOT chamber without force. A boolit .4528" and under leads the bore regardless of composition or velocity. Now if I was trying to accomplish this operation, including honing the sizing die, with an instrument capable of only .001" +- accuracy I would be in a pickle.

Reloading isn't rocket as you say, but it does require precision. Now I'm sure I'm going to get blasted by the "I just buy a Lee tumble lube mould, cast out of whatever lead-like stuff I have, and stuff it in the case without sizing" crowd, and I can't argue with them if it works, but one usually gets better results more quickly with precision.

Gear

Gear I'm not going to blast you but have you tried seating that boolit just a little bit deeper? It's not like you're trying a boolit that is really over large. Not much difference between .4531" and 4534". Just a little adjustment in seating depth should make it work. With no difference in the charge. Just a thought.

[jcwit]

Regarding caliber accuracy, if the caliber zero's out over and over it will work for the avg. joe reloading.

If one is taking their measurements out to the 4 digit in other words .000?, you need to start taking heat and cold into the equation, as material will expand and contract this much.

[lwknight]

Dial and digital calipers are good for 1/1000 measurements but, use with a grain of salt so to speak. Till you get very accustomed to them, you can change the reading by varying the pressure of the thumb when measuring. You can definately tell the difference betwen 356 and 358. 357 to 358 might be iffany

I have never found temperature from 30f-100f range to affect the 6" caliper reading.

[jcwit]

If one really wants to get picky purchase a few gauges and check your calibers and mikes at 70 degrees room temp.

Then be sure you do all your measuring at 70 degrees room temp. for accuracy.

Frankly I think we're going over the top here tho.

[chemist308]

Well I slugged my 9 mm bore with a cast 38 round, and it slugs at same (0.355 to 0.354 depending on where the bullet is guaged). I cast a bunch of 9 mm and 38. Based on the fact that 9 mm sized at 0.356 and 38 sized at 0.358--both true to Lee's claims on mold diameter precision and accuracy--I'm not going to re-size these. Making them smaller would be of no benefit or even detrimental, right? The 9 mm mold I'm using is Lee's TL356-124-2R.

[Rio Grande]

I've been a QC Inspector for about a million years.
1) If you are on a budget, (and then you ain't shooting Kimbers anyway!) a good Mitutoyo (Japanese) electronic caliper will serve most needs, even for bullet diameter if you are shooting boolits and +/- .0005" will do you (moderate loads). About $100
2) If you are serious or will be moving to advanced reloading, get the calipers first, then a good quality electronic digital readout micrometer (I like Mitutoyo, or mickeymoto as some people say, haha), about $100 again.
3) Chinese stuff isn't necessarily junk, but it's hit or miss. Sometimes very good, sometimes disappointing. If you are REALLY on a budget, they will do, but I wouldn't use Chinese calipers for boolit diameter unless they were carefully checked out by a friend who works in a machine shop and knows what he's doing.

[243winxb]

Mitutoyo micrometer. :coffeecom More here, with photos http://castboolits.gunloads.com/showthread.php?p=695116 http://i338.photobucket.com/albums/n420/joe1944usa/th_IMG_3873A.jpg (http://i338.photobucket.com/albums/n420/joe1944usa/IMG_3873A.jpg)

[Green Frog]

Just and FYI... Horrible Freight has a sale on right now for their 6" digital Cen-Tech for a mere $9.99! I got one just to have a knock-around. Add that to the Lyman dial and the two Mitituyo dial calipers around the place, and I should be able to get some reasonable measurements. I'll still use the mics if the measurement is critical, though. :)

Froggie

[mpmarty]

Reminds me of the man with one clock, he knows what time it is. The man with two clocks is never sure.:kidding:

[captaint]

chemist - Plus whatever on Harbor Frieght. Never caught mine lying, and I have some that cost a LOT more. Enjoy Mike

[donS]

I am an old tool maker and had a lot of precision tools which I no longer had use for. I put it all up on e bay and sold it all at very cheap prices. I would recomend looking for Starrett B&S Lufkin Eatalon tumico fowler or mitutoyo. there are lots of good quality tools going for bargin prices.

good shopping Don S