08-05-2022, 02:08 AM
Klem Wrote:Dt,
That threaded case you screw onto the Hornady OAL gauge will be a different shape to the spent cases from your gun. Your gun's spent cases are a closer mimic of the chamber because they have expanded to take its shape. The threaded Hornady case will have been crushed to death in a factory somewhere to fit all Grendel chambers on the planet.
The threaded case is still fine, but you have to account for the difference between its shape and your chamber's shape. To do this, measure the length from base to shoulder with the Hornady B350 headspace gauge, or even an empty 9mm case. Then do the same with a spent case or two from your gun. Note the difference. If the threaded case is shorter than your spent cases (likely) then add the difference to any measurement you take with the Hornady OAL gauge. If the threaded case is longer than your spent cases (less likely) then subtract the difference.
Another easier way is to use a spent/unsized case from your gun as the gauge. You have to drill out the back and thread it for the Hornady plastic stem. This way you don't have to account for any difference as it is the shape of your chamber.
Hard to know if your chamber is short until you can confirm you have accounted for the difference between the Hornady threaded case and your own spent cases.
You don't need to use Blutack. Gently bring a cleaning rod (I use a length of flexible plastic cord so it's not abrasive) in from the muzzle end and stop it just short of the chamber. Push your OAL gauge in and to get the bullet back our you can give the rod a little press against the bullet to unstick it from the throat.
I do not use the hornady gauge. I truly think itÂ’s Mickey Mouse. Thats why I use fired cases from my rifle