Problem with reloaded ammo.

First topic message reminder :

I loaded up 25 rounds of ammo to check if I'm doing things properly.  As per an earlier thread, the info is:

• Magnus #801 bullets, 45-185 grain, BNWC .452 did.
  
• 4 grains Bullseye
  
• OAL 1.130"
  
• Crimp: 0.469
  

The good news is that when the ammo shoots, it's better than anything I can remember testing from the past.  Here's a photo - shot with the heel of the gun on a sandbag, and for one shot I could feel something move slightly, which explains the bad shot - very happy so far:




So far so good, but here's the problem.  While the gun shoots fine when I put one cartridge in the magazine, when I put more than one in, the second round will not fire.  The trigger behaves as if the grip safety is on - the trigger moves so far, and then won't go any further.  I did this several times, and it's very repeatable.  Here are two rounds after ejecting them from the gun:

Another option is to use your case gauge.  Insert the loaded round in the opposite end, of course it won't go in, it sits on top, so now you have a nice surface to hold your calipers against while you measure the crimp. 
- Dave

The pic you just posted is an exaggeration, delete it from your mind.

Brilliant!!!   So easy! 

One finger to push the case against the shell holder, and the shell holder can align the calipers at the very end of the case.  Works great!!!

Wonderful idea!!     ....thank you!!

dronning wrote:Another option is to use your case gauge.  Insert the loaded round in the opposite end, of course it won't go in, it sits on top, so now you have a nice surface to hold your calipers against while you measure the crimp.....

Why don't you post that in a thread all by itself, using my photo, and it can either be made into a "sticky" or placed in a new thread of Great Ideas ?

Having searched for an hour or so to see what has been posted on the 'net, there were lots of discussions, and lots of ideas, but nothing a good as your suggestion.  It takes a guessing game, and replaces it with an exact measurement.  

We can even give the technique a name - how about "Dronning a Crimp" ??

I can't take credit for it, I read it somewhere.
- Dave

Geez, and I'm a machinist! Yes, 15/32

dronning wrote:Another option is to use your case gauge.  Insert the loaded round in the opposite end, of course it won't go in, it sits on top, so now you have a nice surface to hold your calipers against while you measure the crimp. 
- Dave

The pic you just posted is an exaggeration, delete it from your mind.

I tried this last night and my measurement that way was 0.015" greater than measuring at the tip of the case (I open up the jaws a bit at a time until both sides of the case will enter the jaws).   That might not be enough difference in crimp to change accuracy, but if you are trying to replicate someone's recipe, you might as well ask how they measure crimp and do it the same way.

The method you suggest would work if my calipers were "knife edged" but mine (like most) are square edged.  Mike's photo shows the square edge.