Case neck thickness measurements

[Bart B]

Cerrosafe also gives you a good tool to measure the rest of your chamber and a look at the quality of it, It will show the actual free bore, lead angle and throat condition also.

Have you ever measured a Cerrosafe cast to measure the chamber's out of round condition?

 

[Trickymissfit]

+1
I like the micrometer stands because they leave your hands free to accuratly measure with
a good micrometer.

In my last post I left out one important method of measuring the neck/chamber.

I personally find inside micrometers difficult to use in the confines of the chamber, especally the
neck area so I use Cerrosafe and make a casting of the chamber.( it is dimensionally stable between
30 minutes to 1 hour) and it is easy to measure.

Cerrosafe also gives you a good tool to measure the rest of your chamber and a look at the
quality of it, It will show the actual free bore, lead angle and throat condition also.

I also use a ball micrometer to measure neck wall thickness and a good (Starrett or Mitutoyo)
micrometer for all other dimensions for the accuracy of my measurements.

J E CUSTOM

I have a couple sets of small hole gauges that I will get a reading of the case I.D. with. Then measure the gauge head with a micrometer. Then of course measure the O.D.. Time consuming, but pretty accurate. Bigger I.D.'s can be measured with a Unimic pretty easilly, but won't work on the small stuff.
gary

 

[TracySes23]

I have a couple sets of small hole gauges that I will get a reading of the case I.D. with. Then measure the gauge head with a micrometer. Then of course measure the O.D.. Time consuming, but pretty accurate. Bigger I.D.'s can be measured with a Unimic pretty easilly, but won't work on the small stuff.
gary

I also use small hole gauges to measure the neck bore of my chamber. You're correct, it's time consuming considering there's no room to adjust the small hole gauge while it's in the bore, at least not on my rifle. I adjust it in very small increments until I begin to feel resistance as I push it slowly through the neck bore. I've had to make as many as 8-10 adjustments to finally get the feel of any resistance, I then back it off slightly & approach that point of resistance a couple of more times to insure I'm measuring constantly. Extreme accuracy requires a very sensitive touch when measuring. my measurements are always within .0001" of each other.

Spencer

 

[Bill Johnson]

Have you ever measured a Cerrosafe cast to measure the chamber's out of round condition?

That's how I check chambers. 1 pound from Rotometals last a lifetime and once you've done it, it's too easy. I've done just about every rifle I own and I know I've done every revolver cylinder.

If you miss the 1 hour mark to measure, the difference is calculable.

Chamber Casting Alloy Ingot

 

[TracySes23]

That's how I check chambers. 1 pound from Rotometals last a lifetime and once you've done it, it's too easy. I've done just about every rifle I own and I know I've done every revolver cylinder.

If you miss the 1 hour mark to measure, the difference is calculable.

Chamber Casting Alloy Ingot

I've used the chamber casting alloy before (Cerrosafe) I think it's called, but for measuring the neck diameter of a bore, small hole gauges are faster. But, I can't use small hole gauges for a complete chamber unless it's one of the shorter, straight walled cases. The only time I needed to cast a chamber was on an 8mm Nambu, which I was considering reaming to a caliber where ammo was more readily available. As I researched more on the subject I changed my mind. Now I'm glad I did, since I still own it & it's more valuable than the $50.00 I paid for it back in the late 60's. I think it's unfired, but I don't know how I can prove it.

Sorry for rambling on, it's an "old man" thing.

Spencer