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can a .500 a-square be built on a .340 weatherby action?

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27 August 2002, 11:27
<30-378>
can a .500 a-square be built on a .340 weatherby action?
can a .500 a-square or .50 peacekeeper (i think they are both close to the same im not sure which
one is bigger).. be built on a .340 weatherby
action? i want to shoot the .50bmg bullets in it.. i think it will be a fun project that will
be affordable also.. i have been told i could get
2300-2400 with the 750 grain a-max with a 32 inch
barrel. do you think this is realistic? also
who is the best to do the job in the United states..also what problems would i need to
watch for.. would i need to buy a bigger bolt
or could i just have that one opened up and be
safe for full house loads.. give me all your
opinions.. all loads and experiences are welcome.. and advice too.. yes i do have a
.30-378 but i dont want to use it as i have
way too much money tied up in it... [Smile]
27 August 2002, 12:20
500grains
Are you asking about a Mark V set up for 340 wby as the starting point?
27 August 2002, 15:06
jeffeosso
340? hmm, might be an issue, but anything based off the 378 case WILL.
...
jeffe
27 August 2002, 15:20
Mike375
30-378

The good thing about the Wby mark V action (or bad thing depending on your point of view) is that the action rails are not involved in feeding.

Thus, if you buy the magazine box and follower for any of the 378 based calibers ansd have the bolt face opened, you are there. O the other hand if you only want single shot then just open the bolt face.

If want a repeater, apart from the magazine and follower, the actions using the 378 case have a small notch cut out of the right hand side of the reciever so as to allow a loaded round to cleanly eject.

Mike
27 August 2002, 16:41
PC
It can be done as Mike said on the .378 based cases. There was a couple for sale at a shop near my place. I never saw the rifles personally, I was offered one when contemplating building my .585.
27 August 2002, 18:05
John Ricks
You will need the 378/460 magazine box, follower and the extractor (big case extractor is different from the 340/300 extractor).

Then machine out the magazine box opening from the bottom of the receiver, open the bolt face, and mill out the bolt stop groove in the bottom of the bolt so the bolt can go back far enough to feed the longer cartridges. And the above mentioned notch.

Easy job, but requires carbide end mills and a good sturdy vertical milling machine.

The 500 A-Square has considerable recoil, so you also need a second recoil lug on the barrel and a strong stock that is adequately reinforced in the right places.

[ 08-27-2002, 09:06: Message edited by: John Ricks ]
27 August 2002, 19:22
<30-378>
i just want a single shot.. so opening up
the bolt face and adding a second recoil lug
would do the trick? i was afraid the gun might
blow up in my face!! because of the smaller bolt
being to weak..