Pin Gauges: Which to check .357 and .44?

[RG1911]

I would like to check the cylinder mouths on my .357 (S&W, Ruger OM Blackhawk, Ruger GP100) and .44 (Ruger OM Flat-top) revolvers before updating my cast bullet sizing dies.

Rather than buying one (or 2) large sets, would anyone happen to know which selection of pin gauges I should buy? And can you verify that I should get the "minus" gauges?

Thank you,
Richard

[DougGuy]

Contact Meyer Gauge they sell singles. You do need the Z minus pins, -.0002" and you need the half thou increments. for the 357 I would get .356" .3565" .357" .3575" .358" and .3585" for the 44 you may need a bit wider range, .429" .4295" .430" .4305" .431" .4315" .432" and .4325"

This will likely cover the range that throats are now, and finishes where you would ideally like throats to be. I always finish 9mm and 357 to .3585" and suggest using .358" boolits, and the 44 could be either .4315" for use with .431" boolits or .4325" and size to .432" *IF* any of the throats are already larger than .4315" and if all throats are small enough to hone them to .4315" then I would suggest that dimension.

The issue with stock factory cylinders is that the throats are more often than not, uneven in sizes. You will get a gage pin that will go in 4 or 5 throats but not the last one, etc.. Very common.. I would suggest updating the cylinder throats to consistent sizes before updating the dies, you can always size to fit the new throats but quite difficult to size to fit uneven throats.

[KenH]

Just buy the full set of pin gauges from 1/4" to 1/2". Those will run around $100 for a decent set. There was a link to a nice set for $100, but don't remember where. By the time you add up all the pin gauges listed for the two calibers you've paid for the full set. I never knew how handy a pin gauge set would be until I purchased one.

[Wheelguns 1961]

You can usually get a set on ebay for around $100.00 .251-.500 minus myers

[RG1911]

Thank you. I've looked into that route on ebay, but the currently-listed sets are either too small, plus, or $375. I think I'll check on the total for the individual pins.

Richard

[RG1911]

Any thoughts on this set? I'm not sure if the "English" means that it's different from what I need.

Meyer Gage .251" to .500" Minus Black Oxided English Class ZZ Gage Set

https://www.amazon.com/Minus-Black-Oxided-English-Gage/dp/B01N3YHVDO

Thank you,
Richard

[KenT7021]

I bought a set of .251 to .500 minus gages from Amazon for less than $100.00.They were HFS brand and serve my purposes.They shipped Amazon Prime.

[NuJudge]

When I pin gauged a relatively new S&W .44 Magnum cylinder's throats, I was amazed that they were very snug on a .428" pin, and would not pass a .429" pin.

[DougGuy]

By the time you add up all the pin gauges listed for the two calibers you've paid for the full set.

Not true at all. Those would be under $50 before shipping. Try and find a full set for that.

Also, .001" increments are too coarse to measure cylinders. You NEED the half thou pins to be accurate.




Meyer Gage .251" to .500" Minus Black Oxided English Class ZZ Gage Set

English just means it is decimal and not metric, English is what you need. ZZ means -0002" and minus means it is .0002" under which is the exact pins you need for firearms measurements. I cannot stress the importance of getting the half thou gage pins as well, .001" is not accurate enough.

[KenH]

Here's a set for <$100. I seriously doubt 1/2 thou will make that much difference, but am open to convincing.

[RG1911]

Not true at all. Those would be under $50 before shipping. Try and find a full set for that.

Also, .001" increments are too coarse to measure cylinders. You NEED the half thou pins to be accurate.



English just means it is decimal and not metric, English is what you need. ZZ means -0002" and minus means it is .0002" under which is the exact pins you need for firearms measurements. I cannot stress the importance of getting the half thou gage pins as well, .001" is not accurate enough.

Thank you. Those were my next questions. Will get the individual pins this time and keep on the watch for a full set of ZZ minus pins for other work.

Cheers,
Richard

[EMR]

Not true at all. Those would be under $50 before shipping. Try and find a full set for that.

Also, .001" increments are too coarse to measure cylinders. You NEED the half thou pins to be accurate.



English just means it is decimal and not metric, English is what you need. ZZ means -0002" and minus means it is .0002" under which is the exact pins you need for firearms measurements. I cannot stress the importance of getting the half thou gage pins as well, .001" is not accurate enough.

Since the OP’s question has seem to be answered, what pins do you recommend for a 500 Magnum? I felt it would seem silly to create a new thread for this question.

[RG1911]

Thank you. Those were my next questions. Will get the individual pins this time and keep on the watch for a full set of ZZ minus pins for other work.

Cheers,
Richard

Just FYI, I bought 16 Z-minus gauges from the Gage Shop (www.gageshop.com) for $3.36 each, so $53.76. Then shipping of $23.41 (ouch) for a total of $77.17.

Richard

[KenH]

That gageshop has some of the best prices around on pin gauges! I wish I'd known that before I finished up my set. I've got two sets, up to 1/4" and 1/4" to 1/2" and boy are they useful! I'd like to have the 1/2" to 5/8", but might wind up geting a few rather than the whole set.

[gpidaho]

I have two sets. The first is .061 to .250 and the other .251 to .500 The first set I bought on the sales threads here at Boolits for $40 the larger was new and purchased on line for $99 with free shipping. You don't know how handy these can be until you have them. I use mine a lot. Gp

[Willbird]

Also worthy of mention, might draw some fire here but :-).....just use Mititoyo digital calipers :-).

I have been using them since the mid 1980's and each generation gets better and better, but over the years I have worked in a LOT of shops where I had access to master ring gauges of all sizes, the Mititoyo digital calipers were always within .0005" when I measured a master with them, probably a half dozen sets of 4" and 6" calipers over the years.

I LOVE pin gauges, have cheap chinese sets all the way from the .06" range clear up to nearly 1"...but I trust my calipers too :-). or a pure lead bullet mashed a bit to upset it, then tapped through a throat with a wood dowel.

One thing they always stressed in GOOD shops was to use 2 or three "methods" to confirm a critical dimension, that will encourage you to think on something too. Learning how to use a good (starrett) telescope gauge is a good skill too. Some methods can detect an even numbered out of round, elliptical, or square, the pin gauge cannot.


I have worked in a shop that had whole and half thousance pins, and + and - too....they are a really nice thing to have....but they are not the only way to measure a hole. The "plus" are 0 to +.0002...the "minus are 0 to -.0002...so once you throw in hole and half and both plus and minus you can narrow a hole size down to within .0002

I'll debate the need to know throat dia within .0002" though. IMHO the gun is not going to sweat a bullet a half thou bigger than the throat.

Bill