What a cool idea

[garandman]

I recently purchased a 338NM barreled action from Southern Precision Rifles,and built it up...

Well, unexpectedly, Greg reamed a duplicate chamber from an extra section of barrell for measuring the exact cartridge OAL to the lands.

Thanx, Greg !!!

 

[280nosler]

Most smiths are willing to ream an extra chamber as a gauge for a fee. Most fees run between $60 and $100.

 

[garandman]

No charge on this one.

 

[280nosler]

No charge on this one.

Even better.

 

[xdeano]

They are great for getting coal during the first few hundred rounds until the throat starts to move. It is called a stub gauge. They work well.
Xdeano

 

[garandman]

Hornady agreed to make me 2 338NM modified cases for when the throat begins eroding. $30

 

[selfbowhunter]

this also works to know EXACTLY how much you are bumping your shoulders back! I make them for most of my builds and use them regularly to check headspace during die adjustments.

chuck

 

[RugerSlinger]

this also works to know EXACTLY how much you are bumping your shoulders back! I make them for most of my builds and use them regularly to check headspace during die adjustments.

chuck

This is exactly what I use them for too.

 

[Edds]

If I was going to use one for checking headspace, I would want it longer than that one.

 

[garandman]

I was thinking a bit shorter on the bullet end so the bullet protrudes beyond the barrel stub, and you could get a OAL gauge on it from the base of the case to the tip of the bullett.

 

[Edds]

Measuring from the base to the bullet tip doesn't tell you anything about headspace.

 

[Graham]

What a cool idea

Measuring from the base to the bullet tip doesn't tell you anything about headspace.

Exactly. In fact, it tells you little more than nothing at all.

 

[E. Bryant]

Base of the round to the bullet tip tells me whether or not it'll fit into a magazine... but a gage isn't necessary to make that measurement.

 

[selfbowhunter]

If I was going to use one for checking headspace, I would want it longer than that one.

why longer? it only needs to be as long as the shoulder and neck of the case. in fact, I don't generally run the reamer in the entire depth of the shoulder. all you do is take a fired case, insert it in the "gauge" and measure it. then take a sized case and do the same. tell you how much headspace your creating with your size die. you can use the same "gauge" to check throat erosion as well.

chuck

 

[Edds]

why longer?

Because I would prefer to measure from the case head to the top of the gauge.

 

[nexusfire]

did you use a fired case? I could never figure out how to work that thing.

I recently purchased a 338NM barreled action from Southern Precision Rifles,and built it up...

Well, unexpectedly, Greg reamed a duplicate chamber from an extra section of barrell for measuring the exact cartridge OAL to the lands.

Thanx, Greg !!!

 

[garandman]

did you use a fired case? I could never figure out how to work that thing.

Yes. The bullet has to fit somewhat snug in the case as you remove it from the stub.

 

[garandman]

Measuring from the base to the bullet tip doesn't tell you anything about headspace.

It tells me OAL... which I've used with great success to tune my loads for accuracy.

Basically where the lands are.

 

[Edds]

It tells me OAL... which I've used with great success to tune my loads for accuracy.

Basically where the lands are.

Read post #13.

 

[Graham]

What a cool idea

Basically where the lands are.

Yup, tells ya basically where the lands are: Basically forward of the throat somewhere there; that's where them lands ends is.

 

[garandman]

Read post #13.

I use Hornady's gage with the modified case to find the lands, Then I back off 10 / 20 / 40 thousandths...whatever. I am told 338NM likes to be just off the lands.

I can do the same thing with this stub gage....until the throat erodes.

 

[selfbowhunter]

Because I would prefer to measure from the case head to the top of the gauge.

then move your calipers over to the edge......

 

[downlow]

Big time saver. My 'smith gives me one with every new build.

 

[Edds]

I can do the same thing with this stub gage.....

Yes you can. It will work well for that.

 

[Edds]

then move your calipers over to the edge......

I don't want to. I want a longer gauge.

You don't even need a reamer to make a gauge to check headspace the way you check it. A simple stepped bushing will work.

 

[msalm]

This stub works very well for two things... One it allows you to measure exactly where your bullet will touch the lands without chambering a round in the rifle... And also measuring the amount you are setting back the shoulder when sizing. It is cut w/ the same reamer and same barrel....what the hell is there not too like about that? I make one with all my custom AR's as it makes things much easier to set-up. Use your caliper and measure from the base of the case to the end of the gage. If you have a bullet seated long it will tell you exactly how much, if you are sizing brass it will tell you exactly how much you are setting the shoulder back w/ a before and after measurement.

 

[selfbowhunter]

I don't want to. I want a longer gauge.

You don't even need a reamer to make a gauge to check headspace the way you check it. A simple stepped bushing will work.

it might "work" but a gauge that uses the actual cartridge shoulder should be much more accurate IMHO.