Chamber Length Gages

[sentry1]

I recently came across these: Sinclair Chamber Length Gage and want to get some more info.

Has anyone used these? Is there a significant benefit to be had from knowing the exact length of your chamber for a bolt gun or AR?

 

[FLIGHT762]

Re: Chamber Length Gages

That gauge will only give you the length of the chamber and will indicate what your maximum brass length will be in that chamber. As long as you trim your brass at or below the SAAMI maximum (2.015" for 308 Win), the gauge is not really necessary.

I did buy the gauge and found my two 308 Win. chambers (one with a short throat) both measured 2.040" as the maximum brass length.

Once you measure your chamber length, you will never need to use the gauge again in that rifle. All of the years I was so anal about trimming below 2.015" and in reality, I could have let the brass grow to past 2.030". I actually laughed out loud when I got the measurements.

The gauge isn't expensive, but if you're curious, buy it if you want to.

A gauge that is well worth the money and you will use it very often is a shoulder bump gauge like the one Hornady makes.

 

[sentry1]

Re: Chamber Length Gages

No, it's definitely not a huge expense.

Is brass life appreciably extended by trimming it to .01" below chamber length?

 

[FLIGHT762]

Re: Chamber Length Gages

No, I don't think it extends brass life. It just means not trimming as often and not getting paranoid once the brass starts reaching 2.015".

 

[sentry1]

Measuring Chamber Headspace

Thanks.

Next question: What tool can I get to measure the exact headspace in my weapon's chamber?

 

[Deadshot2]

Re: Measuring Chamber Headspace

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: sentry1</div><div class="ubbcode-body">Thanks.

Next question: What tool can I get to measure the exact headspace in my weapon's chamber? </div></div>

A fired case and a Hornady Headspace Gauge. <object width="425" height="350"> <param name="movie" value="http://www.youtube.com/v/P-UrMTyJ1_E"></param> <param name="wmode" value="transparent"></param> <embed src="http://www.youtube.com/v/P-UrMTyJ1_E" type="application/x-shockwave-flash" wmode="transparent" width="425" height="350"> </embed></object>

The fired case will spring back one or two thousandths, depending on when annealed last. I like to make the measurement with a freshly annealed case.

For fitting a bolt or changing a barrel, don't use this method, get a Forster Headspace Gauge, one for Go and one for NO Go. They're about $30 ea.

 

[insight3b]

Re: Measuring Chamber Headspace

To get the exact headspace you need to cast it with cerrosafe
http://www.midwayusa.com/product/462291?cm_vc=S014