How can I measure the shoulder height of rifle shells?

[jayjay1]

Hi everyone!

I´ve got a bunch of rifle shells (.223 Remington) from an earlier reloader.

He told me, that he is unsure because of the shoulder height.

Hhe has used a wrong shellholder to calibrate them sometimes and means, that some/most might have a too low shoulder height because of that.

So I don´t want just to reload them, having a lot of malfunctions, and then have to unload them afterwards.

But how can I measure the shoulder height of rifle shells?

Need some help.

[fishsticks]

Hornady makes a tool for this. http://m.hornady.com/store/Headspace-Gauge-Kits/

[SevoTT]

RCBS precision mic set.

[808win]

By "shoulder height", is the “earlier reloader” referring the dimension from the face of the case head to the case shoulder datum at a diameter of 0.330” for a .223 Remington case? The SAAMI (Sporting Arms and Ammunition Manufacturers' Institute, Inc.) specification for this measurement is 1.4666-.0070 inches. Refer to the SAAMI cartridge drawing for the .223 Remington.

YouTube has several videos of individuals demonstrating the use of a .223 Remington case gauge or case gage to check this dimension relative to minimum and maximum dimensions. Case gauges are manufactured by Dillon Precision, L.E. Wilson, Evolution Gun Works, JP Enterprises and others.

Note: Not all case gauges check the case body diameters. Check with the gauge manufacturer to verify that their gauge does specifically what you want it to do.

Note: If the case shoulder was setback too far, it could create a undesirable condition known as “excessive headspace” that may result in a dangerous event known as “case head separation” when fired in a gun.

[ltdmstr]

Check Sinclair for bump gage - one tool with different inserts for different calibers. Insert matches the shoulder and you measure the dimension with a dial caliper. Very simple to use.

[bigedp51]

At one time I used Wilson cases gauges, then tried the RCBS precision mic and then I got smart and bought the Hornady cartridge case headspace gauge. The reason I say smart is because you only need to by the one Hornady gauge instead of buying a gauge for each caliber. And second you can calibrate the Hornady gauge to read true headspace.

Below, I now use the Wilson gauges for pen holder and paper weights since buying the Hornady gauge.

The RCBS precision mic is not calibrated and my gauge reads minus .003 off scale, and you need to buy a seperate gauge for each caliber.

Below a Colt 5.56 Field headspace gauge, 1.4736

The Colt field gauge in my calibrated Hornady gauge

Below a fired case from my AR15 carbine

Below the same case after sizing and .003 shoulder bump.

The Hornady gauge read minus .011 when I measured the Colt colt gauge. I then loosened the set screw between the red and silver halves of the gauge and inserted a .011 feeler gauge between the gauge halfs. With a little wiggling the Hornady gauge would read the true dimension of the Colt gauge and then the set screw was locked down. The Hornady gauge is now no longer a comparator gauge and gives me true .223/5.56 headspace readings.

[jayjay1]

Thanks for that info and the pics you made!

Very kind from you.

Now I´ve found this on u-tube and saw how it works.

https://www.youtube.com/watch?v=P-UrMTyJ1_E

I will order me one.

Get a German beer!

[808win]

jayjay1, please note that bigedp51 said that his "Hornady gauge read minus .011 when I measured the Colt colt gauge". In other words, he determined that his Hornady gauge was off by 0.011" and "calibrated" it by using his Colt field gauge as a "calibration standard". I'm highlighting, not challenging something bigedp51 said in his post.

A case gauge, as I mentioned in my earlier post, can allow one to quickly check the case head face to shoulder datum dimension relative to the minimum and maximum dimensions.

If you need to know the specific dimension, then you may need to use one of the caliper based tools such as the Hornady Lock-N-Load Headspace Kit or Sinclair Bump Gage, micrometer style tools such as the RCBS Precision Mic or Pacific Tool & Gauge SAMMI / Benchrest Case Gauge, or dial indicator style tools such as the Redding Instant Indicator Headspace and Bullet Comparator or Innovative Technologies Digital Headspace Gauge, etc. I can not attest to the accuracy of these tools.

Note: Again, check with the gauge or tool manufacturer to verify that their gauge or tool does specifically what you want it to do. Always follow the manufacturer's instructions.

[SevoTT]

I forgot about the one that i use the most, the Redding instant indicator. I just leave it set up in my turret press. I have used most of the methods listed above, and all will give a slightly different measurement since they measure off of a different datum point on the shoulder. The Redding comes with a calibration case, but I just set zero to a once fired case from my chamber.

[bigedp51]

Also note that bigedp51 is retired and has chronologically gifted eyesight and his new vernier calipers have LARGE digital numbers.

Also note that SAAMI cartridge dimensions have nothing to do with military type chambers or their headspace settings.

Below is a new unfired Federal M193 cartridge and NO-GO on the AR15 is 1.4706 and .008 head clearance is far too much clearance and excessive shoulder bump.

And not all chambers are the same diameter and headspace length as SAAMI "recommendations".

Bottom line measure your fired cases and bump the shoulder back .001 to .002 on bolt actions and .002 to .003 on semi-autos and your brass will last much longer.

[jayjay1]

I go with bigedip an Hornady.

Looks good, pretty easy and fast.

I have to measure roundabout 2000 rifle cases, no RCBS mic for that, no sir.

Thank you all for your engagement.

[KelsonAK]

If you are in a pinch, you can do the same thing with a pistol case of appropriate size. Use an appropriately sized rifle case (or one fired from your rifle to figure out shoulder bump when setting up your dies) and zero your calipers on a pistol case that will rest on the shoulder of your case. Zero and compare to the 'question' case. Fast, easy, cheap.