I have an Interarms Mark X in 458 Win Mag. listed in the classifieds. A member asked if the action and mag box was long enough for the rifle to be converted to .458 Lott. Being a Mauser action similar to the CZ's I would think it's doable but I don't want to give out any incorrect information to a potential buyer.

What do the experts here think about the suitability of this rifle for such a conversion? Here's a link to the post. Scroll down to the end of the thread on page #2.

http://forums.accuratereloadin...1078981/m/5201071752

The inside length on that MK10 magazine is 3.4". The OAL length of the .458 Lott is 3.6". Would have to make the ".375 H&H Conversion" to make it work.

What would you have to do to the magazine? can it be lengthened or does it have to be replaced?

Cut out the front mag box wall and weld in a new longer one; mill out the receiver to match. Just like making any Mauser work with a 375.
I prefer to remove as much as possible from the rear, however, to lessen the amount the needs to be cut from the lower locking surface web.
Not that hard.

I'm sure dpcd's advice is good but I'd be inclined to point out to the prospective buyer that the true merit in this rifle for dangerous-game hunters is that the shortness of the action reduces the chance of African shortstroke when under pressure.

Less is more when it comes to recoil and short loads in the 458WM still equal the ballistics of the old British db rifle calibres thought adequate for everything for many decades.

Absolutely true; I am in no way recommending the Lott; for me it is way too much of a good thing. I am just saying how it is done; not advocating using a Mauser either. There are better ways to go.
And too much recoil.
(Altering the action of a Mauser to accommodate a Lott does not increase the length of the bolt throw, however.) If you extend the mag at the front.

I also had to increase the loading port to the rear by about .200 for positive ejection

there used to be lots of mk10 mag lengh bottommetal floating around -- last time i did one, i just cut it off the rear, extended and tig'ed it . took most of it out of the rear, as i don't like hitting the front until its time for feeding work.. though the lott tends to wrk well on the 458 ramp, just get the back of the rails right

though, honestly, if you do some work with tac/h335 you don't need to rechamber and rework ..

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Originally posted by dpcd:
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(Altering the action of a Mauser to accommodate a Lott does not increase the length of the bolt throw, however.) If you extend the mag at the front.

That's true, too. I don't suppose it adds any strength, though, for full-house loads if thought required.

That stock is also not (IMO) good for much more recoil. If I were going to a heavier cartridge I would want a better stock too. In fact, if you have a good fiberglass stock with plenty of glass fiber in the mag well area you can cut out the front of the mag box and leave it. When Clifton stocked my 375 Ackley MkX I added new bottom metal and there was none opened to the front like Interarms did for the 375. So that's what we did. That was circa 1989. and the rifle has been a 458 AccRel since Jeff created the round. It functions flawlessly with no battering of the front of the mag well.

quote:

though, honestly, if you do some work with tac/h335 you don't need to rechamber and rework

A much more simple approach.