Cheap and chearful OAL gauge Accurate Shooter

ChesterP

Well-Known Member
Saw this and thought some might find it useful.

http://bulletin.accurateshooter.com/2016/08/smart-tool-tip-make-your-own-length-to-lands-gauge/

Certainly cheaper than the various commercial gauges although needs some Dremel skills to make.
Many people that I know use this method. I have commercial OAL gauges but have also modified empty cases for all my calibres to use with this method for determining COAL. It works well but the caveat is that you have to be careful to get the neck tension sufficient enough to hold the bullet firmly enough, but light enough to allow the bullet to move gently into the case when seating. You also need to be gentle when extracting the round so as not to move the bullet position. Personally, I take an average of around 10 measurements when determining oal whatever the method used. I also only cut one slot into the neck, and not multiple slots as shown. You can use a hacksaw blade if you don't have a Dremel but make sure any rough edges are filed off before use. I also drill out the flash hole so that it accepts a thin rod to gently push the bullet back out after each measurement. No reason why this method won't be as accurate as some expensive gauges if great care is taken.
 
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Barkingsnake

Well-Known Member
And an expensive gauge used carelessly will also be pretty ineffective!
I have used the old RCBS gauge in the past but, TBH, I prefer my own adhoc variant without special tooling.
 

Ranger22

Well-Known Member
Mate made one from an old knitting needle, cut the ends off, stuck one end to a modified case and got a rod that fitted up the inside of the knitting needle to push the bullet. Not sure how he locked the rod in position though
 

ChesterP

Well-Known Member
Mate made one from an old knitting needle, cut the ends off, stuck one end to a modified case and got a rod that fitted up the inside of the knitting needle to push the bullet. Not sure how he locked the rod in position though
You shouldn't need to if the neck tension is right. The idea is to feed the cartridge into the chamber with the bullet "seated long", slowly close the bolt, then carefully eject (removing cartridge by hand) with the bullet now seated to the depth of the lands due to the bullet being forced into the case as the bolt is closed. You then mark the bullet at the top of the neck with a marker pen in case it moves and measure COL with a gauge. Repeat at least three times, but preferably up to ten times and take an average. Job done.
 

Ranger22

Well-Known Member
You shouldn't need to if the neck tension is right. The idea is to feed the cartridge into the chamber with the bullet "seated long", slowly close the bolt, then carefully eject (removing cartridge by hand) with the bullet now seated to the depth of the lands due to the bullet being forced into the case as the bolt is closed. You then mark the bullet at the top of the neck with a marker pen in case it moves and measure COL with a gauge. Repeat at least three times, but preferably up to ten times and take an average. Job done.
If the rod can be locked in place it doesn't matter if the bullet stays in the case or not. I have the Hornady oal and modified case, the bullet nearly always gets stuck and needs tapped out.
 

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