Desert Eagle Mk VII caliber swap

T

Tankist

New member
A bit of a specialist question...

So, according to Magnum Research, one would need a kit to convert DE mk VII to XIX in order to switch calibers from say .44 to .357. This kit is not cheap at all and includes a new XIX spec slide.

This sounds a bit off to me though, why would that be the case? The original mk VII slide is built to handle .44, what about just finding a mk VII .357 barrel/bolt/mag and reconfigure the slide for the smaller caliber? Sure, mk VII parts will likely be a pain the ass to find, still it should be a lot cheaper than getting that conversion kit.

Has anyone done this by any chance?
 
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I havent done a conversion but is sounds like getting parts to change it over will be difficult to find. I would also love to find 357 parts to swap it over when i felt but i'm not holding my breath. Of course the factory wants you to buy the whole upgrade kit, more money in their pockets.
 
Sorry, I can't help directly, as I have no personal experience with the Mk VII and MK XIX.

I do have 30+ years experience with the original, now called the Mk I, both the .357 and the .44 Mag.

Other than the obvious "to make more money" I have no idea why they say you need to buy a kit that includes the slide. However, I do have a couple of observations that might be relevant.

First off, have you ever taken the bolt out of the DE slide and then put it back in? I have not. It looks like it is not a terribly complex thing to do, but looks can be deceiving. It MIGHT be that the factory does not want people doing this (swapping bolts) on a regular basis, which one would do for conversion back and forth between the two different calibers.

Not every gun is made to be detail stripped constantly.

Second, and again, I don't know about the later marks, but with my early guns, there is a difference between the .357 and .44 gas pistons, and their method of attachment to the slide. Also there is a slight difference in the recoil spring assemblies.

So, it is possible that the factory only wants you to use a complete slide assy for caliber conversion simply to sell more parts and make more money, but it is also possible the factory wants you to use a complete slide assy so they don't get bothered by users who screw up and damage/wear out the parts from frequent disassembly and reassembly.

The Desert Eagle is a unique species. It's NOT a 1911, Glock, Beretta, Sig, or any other type of service pistol. About the only thing it has in common with other pistols is that it is a semi auto handgun, and it has a hammer.

What works for them is sometimes not the right thing for a DE, and sometimes is completely the wrong thing to do.

Sorry I can't be more help on this question.
 
I have detail stripped a mk VII a few times and its not terribly complicated nor delicate. In fact, it's built like a tank as one would expect for something like this.

Fair point though, I suspect that the piston and recoil springs would have to different between calibers or else, there may be some issues with operation given that .357 is significantly different from .44 in pretty much every way.

That, plus having looked around for a bit... there doesn't seem to be much of a secondary market for used MkVII parts at all.
 
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I too have an earlier version(44mag). Tried for some time to get the 357 conversion and found the few out there to be a fortune. Finally gave up and bought a coonan. Maybe one day if I can get one at a decent price. Loving the coonan though.
 
Bought a 357 barrel "conversion kit" to go from .44-to-.357 (complete w/box and magazine) at a gun show for $250. Thinking I'd hit the jackpot, soon discovered it wouldn't fit because the bolts are different. So I ordered a .357 bolt from Magnum Research only to find it wouldn't fit. Seems there are differences in the slides on MK1, MKVII's, and Mark XIX's. Mine was a labeled as an early MKVII but contained parts that Magnum Research had been using on the MKI. Evidently they used up existing parts and labeled it a the next generation model. They did refund the money for the bolt....but the guy at the gun show is probably still laughing at his good fortune.
 
I'm seeing this as well. So apparently, the safest way to go is just to upgrade upper to XIX spec. This includes barrel and complete slide which will likely run close to 1k new. This may be worth it long term given price difference between .357 and .44 ammo cost. Still that's pretty steep.
 
OR, you can keep your eyes open for an older, used gun, like a Mk I in .357 Mag. You might find one cheaper than the cost of a new conversion kit.
 
Others are correct when they mention you need a different 'upper' for the caliber change with the MKI od VII.

MR sold these conversion kits after the .44 came out.
The kit came in a pouch that contained the complete upper, spring assembly, and a magazine.

Notice the ruber 'O' ring on the magazine body.
I use these 1 1/2 dia. rings in various widths as required on all my DE magazines in all calibers.
The ring allows me to use my off hand under the magazine (as opposed to MRs instructions to not touch the magazine bottom while shooting) while still giving positive function.
The ideal solution for field position shooting.







In this second picture, you can see the gas piston is held in place by a roll pin
and the single spring recoil assembly has no lug on it as the .44 assembly does.
The lug on the .357 is on the slide itself.

Also note the optimistic belt loop on the pouch.
As if you would carry both the .44 and this 2 lb. kit while out and about!



I'll second 44AMP's suggestion to get a second pistol (MKI or VII) instead.

My 50s and .440s are all MKXIXs because they have to be for the calibers.
I would not be at all interested in a .357 or .44 MKXIX given the additional bulk of the slide.

While I have never shot a round of factory ammo in any of mine ( I would faint from the cost!), I can believe the higher cost of .44 vs. .357 ammo.
You will enjoy the .357 in a DE - the original -.
It is the only DE caliber you can shoot from the hip with a light hold (recoil is on par with a light .38 load from an 'N' frame Smith) and have reliable function.

JT
 
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