I am considering buying a Smith & Wesson M&P15 Sport II 5.56 NATO and wondered how difficult it is to convert it to other calibers such as 458 SOCOM or 300 Winchester for when I am hunting larger game than a 5.56 is good for, also can anyone recommend good conversion kits. I am on a budget which is why I don't just get 3-4 different AR's, and am primarily wanting the AR for fun shooting and some hog/coyote. I especially do NOT wanna hunt hogs with my current 30-06 bolt so the AR would be my preferred platform.
Question about conversions
- Thread starter Desmodus
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You'll have to swap out the upper.
That's about it. The magazines
are the same. So for 458, get
a 458 upper.
Any thing longer than will fit
in a .223 mag will require
another gun.
That's about it. The magazines
are the same. So for 458, get
a 458 upper.
Any thing longer than will fit
in a .223 mag will require
another gun.
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A year or so ago Winchester developed the .350 Legend. They did it mainly for folks who have to use a straight wall cartridge if they hunt with a rifle. But, IIRC, it'll also work in a MSR. Several companies are supposed to be making uppers, but current market may be a problem. Might need different magazines.
Given the current ammo situation, this might not help, but several ammo companies are making ammunition specifically for hogs. Someone (Winchester?) is making a load specifically touted as a "Boar" load. In .223/5.56 mm might not be first choice for a 400 lb hog, but should work with more reasonable size game.
Given the current ammo situation, this might not help, but several ammo companies are making ammunition specifically for hogs. Someone (Winchester?) is making a load specifically touted as a "Boar" load. In .223/5.56 mm might not be first choice for a 400 lb hog, but should work with more reasonable size game.
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If you assemble your own upper, you will need the barrel of your choice with a corresponding bolt and magazine, plus the upper, gas system, and hand guard.
Hair Trigger
US Veteran
Here's a good read on building an AR. There's a couple of new calibers been developed for the platform since this was made, but the basics are still valid. In most any AR rifle/carbine/pistol caliber, the biggest difference between them is the barrel and bolt. Sometimes that's all you need to change to go from one caliber to another. The main thing to remember when changing calibers is that the cartridge has to be short enough to fit the AR magazine. If what you want is longer than the .223/5.56 cartridge, you have to move up to an AR-10, which will take cartridges like the .308.
How To Build An AR-15 Rifle | Building an AR-15 | MidwayUSA
How To Build An AR-15 Rifle | Building an AR-15 | MidwayUSA
