Shooters Box Tri Step Ammunition Gauge

[Krh1326]

Hi All…

I am having a lot of trouble, wrapping my head around this one, and to make it worse, I have a nagging feeling, that I’m missing something, very obvious and basic… and it’s got me flustered.

I recently started with .357 Sig, and needed a gauge, and Shooters Box came up in search, so I bought it.



I made up some cartridges, and dropped them in. I get them between the first two steps nicely. Now how in the heck am I supposed to get the head between the last two steps, for head spacing ? The head can’t be in two different places at the same time.

Their website has no directions or instructions, and there isn’t any YT vid , that actually discusses the headspace steps. The closest I’ve found, is :

https://youtu.be/scG7GuHYbnA

Can someone please help me understand this, before it wrecks the rest of my weekend?
Thanks

[45_Colt]

It appears that the gauge is for two different things. As you noticed the lower and middle step is for the min/max cartridge length. For gauging cartridges these are the ones to use.

For some reason they felt the need to put a chamber maximum headspace step on the gauge. Not sure how that would be used. Maybe a fired case to see if it expands/extends too far, above the step. That may indicate that the chamber headspace is too large.

Another question would be, does the gauge use the mouth or shoulder for min/max length? SAMMI states mouth, CIP states shoulder. I size to headspace on the shoulder, much easier way to go.

45_Colt

[Krh1326]

The first two steps, say case length. I believe for cartridge length, it’s the notch on bottom of gauge. Oh this thing is nuttier than squirrel turds at the peanut farm.

[MrWolf]

From the looks of it, you don't try and "get the head between the last two steps, for head spacing?". It looks like the last shelf is cautionary for maximum head space. As long as the rim is basically in line with the middle shelf, you are good to go. Anywho, that is how I see it. Folks with more knowledge than me will chime in.
Ron

[45_Colt]

The first two steps, say case length. I believe for cartridge length, it’s the notch on bottom of gauge. Oh this thing is nuttier than squirrel turds at the peanut farm.

Yes to case length, I should not have stated cartridge length as that includes the boolit. So the lower two steps are for the case length gauging. Which can still be done on a loaded cartridge.

Then OAL is by the notch on the bottom.

45_Colt

[Krh1326]

I figured, but how is this gadget supposed to check headspace then? Am I reading this wrong, as MR WOLF is pointing out? This is just a gimmick, as if it passes the case length steps, by default, it passes the headspace steps?

[ulav8r]

Maybe use the third step to check an empty, fired case to insure headspace is within spec.

[dillonhelp]

Most gages check the case length on the front end of the gage for bottleneck cartridges. They are just checking at the back end is all. Just a different way of doing things.

[45workhorse]

I realize that .357 Sig is a bottle neck cartridge.
So here is my question, why can't you use your barrel like a 9mm or .45 ACP? Plunk test?
Or am I missing something! Won't be the first time.

[jetinteriorguy]

Maybe use the third step to check an empty, fired case to insure headspace is within spec.

This makes the most sense to me.

[ioon44]

I realize that .357 Sig is a bottle neck cartridge.
So here is my question, why can't you use your barrel like a 9mm or .45 ACP? Plunk test?
Or am I missing something! Won't be the first time.

I always use my barrels for .357 Sig, 9 mm & .45 ACP to plunk test. Your loaded rounds need to work in your barrel not a case gauge.

[45workhorse]

I always use my barrels for .357 Sig, 9 mm & .45 ACP to plunk test. Your loaded rounds need to work in your barrel not a case gauge.

I do not load 9mm or 357 sig.
But I do load .45 ACP and use my chamber/barrel for the " plunk" test!

[gwpercle]

The first two steps, say case length. I believe for cartridge length, it’s the notch on bottom of gauge. Oh this thing is nuttier than squirrel turds at the peanut farm.

LIKE LIKE LIKE ! ! !

You really don't need a squirrely Gauge ...
Use your guns chamber ... it's the only gauge that matters !

The company is selling you something you really don't need then they give no directions on how to use it ...

If it does fit your Gauge ... can you trust the round to fit your guns chamber ...
...or will you need to test them in your gun before loading too many rounds .

When it comes to buying gauges , ask yourself , is it really necessary , or is the company selling me a useless gizmo ... think about it ...

Hint ... check a few rounds in your guns chamber before loading too many ... or invest in a bullet puller ... now that's a gizmo you will use for sure !
Gary

[popper]

I see a problem with that gauge. The steps actually measure head space! If between the higher of the steps, RESIZE! It does NOT measure case length unless the bottom of the gauge is closed. Example, a Wilson gauge has base steps that set min/max length from a shoulder DATUM point. When proper sized case is inserted, head will be between the steps. If the neck is too long, it will protrude from the front. That sets the SAMMI spec. It is not necessarily your rifles chamber. Use your chamber as a guide, set everything to what fits your chamber. Compare with chamber gauge. Difficult to do on autoloaders (ARs). Make sure if autoloader with floating FP (AR) is NOT set for max H.S., A.D. may occur.

[mdi]

I think I would use the case length feature and plunk test a finished round for chambering/headspace.