Over all length gauge?
- Thread starter KyleC
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Mikecr
Well-Known Member
See, we're talking about a tool that is not for cartridge OAL, and it certainly does not measure overall length of chamber.
Initially I thought the OP was talking about OAL attachments to calipers. That a set screw for one of the attachments was failing.
Then OP declared that the tool he was talking about was for finding touch (or max) OAL, even while Hornady simply merchandises their tool for measuring OAL..
That's where I brought up the potential for confusion of terms.
OAL, or COAL, is an attribute that you set, regardless of land relationship. It is simply measured with calipers.
This Hornady tool extends a bullet from shoulder datum to land contact. That's all it does. From there you measure that special OAL with calipers.
Chamber length stops just in front of trim length. It does not include freebore/throat or leade. Different tool for measuring chamber length.
Initially I thought the OP was talking about OAL attachments to calipers. That a set screw for one of the attachments was failing.
Then OP declared that the tool he was talking about was for finding touch (or max) OAL, even while Hornady simply merchandises their tool for measuring OAL..
That's where I brought up the potential for confusion of terms.
OAL, or COAL, is an attribute that you set, regardless of land relationship. It is simply measured with calipers.
This Hornady tool extends a bullet from shoulder datum to land contact. That's all it does. From there you measure that special OAL with calipers.
Chamber length stops just in front of trim length. It does not include freebore/throat or leade. Different tool for measuring chamber length.
That's a design issue, imo. When I got my first one 20 years ago (like others, have both straight & curved), it looked like a potential failure point. I thread the modified case down until it's firmly against the gage shoulder so as to put the threads under a little tension. Mine are stored by themselves (rather than loose in a drawer) when not in use & my bench area has Harbor Fright interlocking foam squares on the floor. They're for comfort but have saved both tools & firearms when I've oopsied something.
If you have hard flooring, I can see that thin neck bending if the gage lands threads down.
It is, regardless of how others view it. The tool allows you to measure both the CBTO and COAL.
COAL
CBTO
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Now you guys are making me feel lucky. I have used mine on several rifles and never had a problem. I use measuring tools at work all the time and will not loan them out due to being easy to damage.
I've bought mine back in '15 and have used them on several different BA's and AR's without any issues. They are flimsy, but get used carefully.
I use the Whidden universal bushing fixture on my calipers. Ordered the bushings .002 smaller than bore to measure close to the ojive. I found the COAL measurements to be very inaccurate, too much variation in the bullet's tip to ojive measurements so my distance off jam was never consistent.
I use the same tool with different bushing to measure shoulder bump as well.
For me, this was money very well spent.
I use the same tool with different bushing to measure shoulder bump as well.
For me, this was money very well spent.
I must be lucky too. Used it on AR's, Bolt Action, FN-AL, AK's, still going strong. Must have gotten one of the good ones like you
QuietTexan
Well-Known Member
If you care about accuracy past 1k yards, buy Litz's 3rd book - he goes over sorting bullets and the resultant impact on precision. If your bullets are so out of length spec that you can't get consistently matched BTO and COAL you need better bullets, or to read the part in his 2nd book about trimming/pointing.
Varmint Hunter
Well-Known Member
I have been using that gauge for many years, even before it was a Hornady tool. Hornady bought the rights to the tool from Stoney Point. I find that it works quite well and gives repeatable results once you get accustomed to using it.
I can't imagine how your gauges are getting broken because no force is used in its operation.
Mikecr
Well-Known Member
So,, if you measured it (with calipers) in a car, you'd have an OAL CAR?
The truth is you don't need anything but calipers to measure OAL.
You need a gizzy with calipers for CBTO.
Both OAL, and CBTO, are in themselves separate from max/touch lengths.
You seem to be the only one having an issue with it. Press on with what works for you and we will do the same.
Once your throat wears, your gizzy doesn't match or provide the answer to how much erosion
