Can a 1917 endfield action work with 600 overkill

Hugh1234

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Hello I was wondering if it is possible to build a 600 overkill from a 1917 endfield action or is that to much or too big for that action?
 
Yes, feed rails will need to be altered too and new magbox. But again where are you going to get brass??? There is no parent case and its no linger being made.

No one is going to sell you brass from their stash, a $10,000 gun isnt worth anything without brass.

As someone pointed out a 550 Magnum is your best option for a true big bore bolt gun. Buy a CZ550 416 rigby and rebarrel, use 460 wthby brass.
 
It might be possible but barely I think. They build 416 Rigby on 1917 and it is 0.050" longer overall cartridge than 600 Overkill. So mag box can be lengthened and ejection port should have enough clearance. But the bolt face is cutting it close. Outside diameter of my P14 bolt head is 0.69" and rim diameter of 600 Overkill is 0.64". Again, only fifty thousandths difference. One would need to be careful opening the bolt face to such close tolerance to bolt outside diameter. If the lathe cutter chips and knocks off what's left of the bolt face rim, the cartridge probably would not mate up properly with extractor when feeding from the magazine. Also, won't be a lot left of claw after extractor is modified to accept such a large rim diameter. Would there be enough remaining of extractor to prevent it from breaking? Maybe ... but just barely.
 
Your best bet, would be to fit it on a GMA action. I know Corey at Bayou told me he can hand turn 600 Overkill, but that might be exclusive to his customer base. Once you hit big bores, nothing is inexpensive!

I know Rocky Mountain Cartridges makes 600 Overkill, but you can't push them too hard, due to weaker brass alloy used.
 
I use a P14 bolt for any caliber larger than a standard belted magnum
LOTS of spare metal on the left side of the P14 bolt for these big boomers, yes the rest of the rim of the bolt is thin, but the left side is good

I have built over a dozen 505 Gibbs on Enfield 14 and 17 receivers, and have another one in the shop I am working on

It takes the proper machine and hand work, a new extractor with the thicker M70 hook, and longer overall length to stay in the rear bridge, a new proper magazine unit and follower also a good magazine spring for these big conversions

Simply not a normal type of everyday garage gunwork

WCF
 

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