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AH ambassador
This one was a full custom in every sense of the word. The 6.5 Grendel-Max was a cartridge I developed from the standard Grendel cartridge as I felt there was more to be gained from it but I still wanted it to be house in one of the small Mini Mausers. I felt that if the shoulders were moved forward and the OAL was lengthened I would gain case capacity and considering that I was going to be using a bolt action rather than a semi auto, felt that it was a very workable challenge to see what I could make this little powerhouse do.
I wanted to be able to use the standard loading dies and having a liking for the Wilson straight line BR dies from previous BR loading for the 20VT and 7x57, I got a set to do the neck sizing and the loading and a Forster FLS die for the forming. It was going to require a little different approach to brass forming and loading but I thought that if it was as successfull as I imagined then it would be good for others without having to go to custom loading dies and fortunately that is how it turned out. I bought some brass and made what I intended to be the go guage for chambering the 6.5 barrel I bought.
First step was to increase neck dia with a 30 cal expander button
Because I needed to have the shoulder moved forward by .05 I made a .05 spacer for the top of the shell holder and epoxied it in place. The (white) .006 shim was for when I formed the rest of the cases so it would leave them with a .006 crush fit in the chamber for fireforming
When the case was lifted into the FLS die it would leave the shoulder long by .05 but because this was to be the go guage I wanted the remainder of the neck formed out to the correct shoulder so I then fitted a spent primer filled the case to half the neck height, made a tight fitting rod and used hydrolic pressure to form the full case shoulder through the top of the FLS die. I then was able to load a 123gn A Max so the start of the heel was right at the new shoulder - neck junction. The cartridge was now 2.405 OAL compared to the 2.225 for the standard case and a 10% capacity advantage
In light of this I drew up the reamer specs I wanted and sent them off to Mansons.
While I was waiting for that bought an Interarms Mark X mini mauser action.
The tiny little bolt handle was never going to be exceptable for me so it was cut off and I made a replacement one from a piece of 7/8 bolt. A drill locked in the vise served for a lathe and files for lathe tools.
With that done I cut the rear off the mag box and made a dummy extension to check function with the longer cartridge.This removed the attachment screw location that holds the mag box in place but I figured it was unnecessary anyway and this proved to be the case.
I had to do a little rail work as the action had originally been for the smaller 223 case but it worked so I sent it to the GS to have this extension done and the barrel fitted. He used my dummy case as go guage and with a piece of tape on the base of the case for a no go guage.
Now all I needed was a stock to carry this little gem.
I wanted to be able to use the standard loading dies and having a liking for the Wilson straight line BR dies from previous BR loading for the 20VT and 7x57, I got a set to do the neck sizing and the loading and a Forster FLS die for the forming. It was going to require a little different approach to brass forming and loading but I thought that if it was as successfull as I imagined then it would be good for others without having to go to custom loading dies and fortunately that is how it turned out. I bought some brass and made what I intended to be the go guage for chambering the 6.5 barrel I bought.
First step was to increase neck dia with a 30 cal expander button
Because I needed to have the shoulder moved forward by .05 I made a .05 spacer for the top of the shell holder and epoxied it in place. The (white) .006 shim was for when I formed the rest of the cases so it would leave them with a .006 crush fit in the chamber for fireforming
When the case was lifted into the FLS die it would leave the shoulder long by .05 but because this was to be the go guage I wanted the remainder of the neck formed out to the correct shoulder so I then fitted a spent primer filled the case to half the neck height, made a tight fitting rod and used hydrolic pressure to form the full case shoulder through the top of the FLS die. I then was able to load a 123gn A Max so the start of the heel was right at the new shoulder - neck junction. The cartridge was now 2.405 OAL compared to the 2.225 for the standard case and a 10% capacity advantage
In light of this I drew up the reamer specs I wanted and sent them off to Mansons.
While I was waiting for that bought an Interarms Mark X mini mauser action.
The tiny little bolt handle was never going to be exceptable for me so it was cut off and I made a replacement one from a piece of 7/8 bolt. A drill locked in the vise served for a lathe and files for lathe tools.
With that done I cut the rear off the mag box and made a dummy extension to check function with the longer cartridge.This removed the attachment screw location that holds the mag box in place but I figured it was unnecessary anyway and this proved to be the case.
I had to do a little rail work as the action had originally been for the smaller 223 case but it worked so I sent it to the GS to have this extension done and the barrel fitted. He used my dummy case as go guage and with a piece of tape on the base of the case for a no go guage.
Now all I needed was a stock to carry this little gem.
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