What can I do to a left handed Ruger MkII stainless/laminate chambered in 7mm Mag to get a big bore?

This 7 Mag is driving me nuts, after pillar bedding, trigger job, recrown, etc. it still only shoots one bullet into 1 MOA.

I want a 40+ caliber thumper in a non-blackpowder factory caliber, so I guess I'm looking at a 458 Win Mag, unless someone can squeeze a 416 Mag into this action.

Any ideas?

Does anyone know a gunsmith that they would recommend for this type of work?

Look up the 416 Taylor....it'll fit in with only a barrel change.

If you wish you can join the crowd in the 416 or .423 AR group....that requires a new barrel and maybe a bit of rail work.....maybe none too.

The AR round a bit more power but the 416 Taylor is roughly equivalent to the 416 Rigby factory loads. We're talking serious whompass here.

Here's some loading data for the 416 Taylor



300 Colorado Semi-Spitzer IMR IMR-4320 73.0 2,653
Remarks: Accuracy poorer

400 Colorado Round Nose IMR IMR-4320 70.0 2,401
Remarks: Best load in this caliber for African game
400 Colorado Round Nose IMR IMR-4320 72.0 2,447
Remarks: MAXIMUM! Do NOT exceed
400 Colorado Round Nose IMR IMR-4320 73.0 2,469
Remarks: DANGER! Blows primers - Do NOT use

400 Hornady roundnose IMR IMR-3031 67.0 2,335
Remarks: average group size (inches): 1.30; maximum


I'd expect the 416 AR to jump velocities about 150'/sec.....and that's going to wake up the old neighborhood!!!

and a photo.....
Thanks to Frank Martinez

fjold--I would bet jeffeosso will weigh in with his wo-cents' worth--and I would listen carefully. He has packed his .460AR cartridge into the Mk II action.

since you said factory AND over 40, your choice is the 458winmag ...

if you are willing to pay for gunsmithing, you might could get a 416 remmag in there... though that will cost in terms of feeding and smithing...

the AR rounds, 416, 458 and 470 (allen 4 7 0) all fit into the ruger package easy. Click on the link in my signature and you'll see them.

but, for bang for the buck, it's the 458 winmag, as those are the most powerful FACTORY rounds that will fit into the action without spending $$$ to make them fit, and if you do, your choices would become 416 rem, 458 win, 458 lott, and 470 capstick (it's nominally a factory loading)

of course you could do an AR!!
jeffe

I've seen a Ruger S/S with laminated stock in 458WM that was perfection ... very nice rifle. Another option would be a 425Express, Savage offered it in a rifle but I'm not sure if ammunition was ever produced by anyone. Most cost effective would be the 458WM ... more interesting would be a 416Taylor.
Cheers...
Con

Thanks guys, I was trying to simplify my brass buying, etc. by going with a factory round but I'm not sure that a 458 would be my first (or fifth) choice.

I just took a loaded 375 round and put it into my 7 mag and I can see that the loading port would have to be opened up to remove loaded rounds.

The loaded round fits between the rails and the bullet catches on the feedramp.

It will take about 3/8" of extra length either off the back wall of the action or the feedramp, or both. This action does have about a 1/4" of extra length that it doesn't need for the 7 Mag rounds already.

So as far as I can see it involves; machining the back wall of the action and the feedramp. Opening the ejection port, shortening the bolt stop, making a new mag box and probably lengthening the bottom metal.

How much in gunsmithing costs am I looking at here?

Of course, then it's a new barrel, recoil lug, and sights also.

There was an article in Rifle magazine about lengthening the M77 MkII. It was made into a .375H&H. A gunsmith in Colorado Springs, High Tech Gunsmithing, might be able do this. The conversion uses the box and floorplate from the longer Ruger rifles.

If you want that left hand 7-Mag to be a left hand 375 H&H...just add money.....and I'd guess about $800 or so.

quote:

Originally posted by vapodog:
If you want that left hand 7-Mag to be a left hand 375 H&H...just add money.....and I'd guess about $800 or so.

$800 is a lot cheaper than any other option for a lefty. I emailed the Hy-Tech group in Colorado last night, so I'll see what they say.