AHR in .550 Magnum

I have loaded dummy rounds as per the above table. My magazine, bottom metal, feed rails needs some work to function the way I would like. Right now it is single stack. I am still in the process of thinking which actions to use for the project. 1) MRC MAGNUM, 2) CZ 550 MAGNUM, 3) GMA MAGNUM.. Have these actions handy.
Krish
Hands down the Granite Mountain Arms African Magnum Mauser action, Krish.
 
Hands down the Granite Mountain Arms African Magnum Mauser action, Krish.
Well originally Gma was going to be 450 Rigby. When I bought the Action I also got a integral barrel that can have a quarter rib,and barrelbad or sight, with integral front site. 450 is marketable easier than 550. MRC IS A 505 boltface. That is my diploma.
Krish
 
Well originally Gma was going to be 450 Rigby. When I bought the Action I also got a integral barrel that can have a quarter rib,and barrelbad or sight, with integral front site. 450 is marketable easier than 550. MRC IS A 505 boltface. That is my diploma.
Krish
Krish, this is a novice question: What is an Integral Barrel & an Integral "Front site" if you find the chance. Thank you.
Integral Front site (I assume)
1695720573569.png
 
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Well originally Gma was going to be 450 Rigby. When I bought the Action I also got a integral barrel that can have a quarter rib,and barrelbad or sight, with integral front site. 450 is marketable easier than 550. MRC IS A 505 boltface. That is my diploma.
Krish
Hmmmmm, decisions, decisions ....
 
@Daniel Cary - When it comes to AHR upgrades, they have changed over the years. In 2018 I got a #2 done which was everything except a wood stock upgrade. I found out later that the new #2 didn’t include several of the things I had included. Best to request to see the invoice that states exactly what was done on that particular rifle.

As for now, it’s my understanding that Wayne is only doing full custom work…no upgrades to CZ’s. Matrix is doing the CZ upgrades now. Although I’m sure he’s providing oversight at some level.
 
@krish - Holy crap! That's awesome.

What, no quarter rib? :ROFLMAO:
 
Beautiful in the white. I suppose the quarter rib will be soldered on. ;)

Looks like an amazing project. Best of luck.
 
Nice GMA action and with John's so called "pregnant" floorplate.
from Krish's barrel pics, looks to be from a 1.35-1.5" barrel blank.
Since a 450 Rigby, I suspect owner was going to use a rear bridge peep sight from Joe Smithson and forgo a rear express sight and qrib.
However, even with a 1.35" blank and a square bridge action, possible to have a qrib and rear sight. Here is one made from a 1.34" blank with a full length rib, in the machine.
rib_breech.jpg


rib_qrib.jpg


rib_front.jpg
 
and to think, Ruger's RSM barrels were built the same way... FACTORY production rifles, not custom...
Yes Sir, Bill Ruger is to be applauded for those rifles! I started a thread on integral barrels for those interested. Note only quarter rib was integral. I suspect this was done this way as could keep the rifle stock barrel channel the same for calibers with different muzzle diameters?
For our 550 magnum, it has the CZ550 contour in the stock channel and then has a second, slower taper to the muzzle to get the diameter.
 
Ruger lost money on the original RSM rifles because Bill Ruger believed that "blue collar buyers" should be able to afford one. Not sure if that was the case moving forward, but I know it was in the begining.
 

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