Sig P320 .357 Sig Conversion Kit 

Loving the art on the wall

Freedom munitions has 357 sig range ammo for less than 50 cents a round. Me and my buddies get together and do a bulk order so we get free shipping. If you want to shoot 357 sig it’s the best option price wise.

Is 9mm equal to or superior to 357 Sig? Let’s think about that for ourselves for just a moment, shall we? I get it that some people pick a side and feel the need to defend their choice, but not to the extent of regurgitating pure nonsense that they themselves were misinformed on. Some ammo manufacturers actually have loads that even surpasses the ballistics of traditional 357 magnum performance. Underwood's 357 SIG Gold Dot for example. Also because it’s a bottleneck cartridge it has the added benefit of feeding more reliably than other pistol rounds. It’s flat shooting and will punch through auto glass like it was butter. It’s literally a 9mm projectile “except” because it’s 200-300 fps faster it penetrates most barriers as well as 10mm yet doesn’t over penetrate flesh, which is welcomed to aid in avoiding collateral damage. It has a flatter trajectory that in turn makes it more accurate and potent at distance. Though the penetration is no greater than 9mm in flesh, the cavity damage is much more devastating making it more likely to stop a threat with less shots. Underwood has a 357 Sig 65g Xtreme Penetrator round that exceeds 2250+ fps out of just a 6” barrel. I don’t know of any other semiautomatic pistol caliber that has rounds capable of such velocities from a handgun. It goes straight through a 3A panel even. At those velocities normally temporary cavities tear. One of the most attractive benefits of owning a 357 Sig is the ability to convert the firearm to 40 S&W & 9mm with nothing more than a simple barrel swap. You also normally can do a 357 Sig or 9mm conversion if you own a 40 S&W firearm as well. That means you can train on whatever platform you’re most comfortable with and whatever ammo is the most affordable, and no it isn’t always 9mm. That means that you are less hindered by ammo shortages… and when you’re done training simply swap out the barrel and ammo back to 357SIG and you’re all set. Sadly on a native 9mm firearm you don’t have any option to do a conversion. I never understood what’s not to like about 357 SIG… well other than ammunition availability and cost being the only negatives I guess, but it is the better round. Keep in mind that when you compare 9mm +P or +P+ to try to achieve 357 Sig performance, 357 Sig is actually cheaper than 9mm. When I searched +P+ to get as close to 357 Sig performance as possible, it was more expensive than a standard 357 Sig JHP round. 9mm +P+ is still only 1300 fps in 124 grain. That’s 50 fps slower than the lowest end 125 grain Sig round at 1350 fps and we’re comparing +P+ 9mm ammo here. Yet the bare minimum 357 Sig performance isn’t even achievable and this is usually attempted in a platform that isn’t even recommended for +P+ or even +P at times. I say it’s best to swap to a 9mm conversion barrel when training and back to 357 Sig right before you’re all done to finish up with 357 to cut that expense down. In most cases the recoil of any superior round can be overcome with training. I do understand that some people are recoil sensitive and are more comfortable with 9mm or other lower recoiling rounds. I understand some just prefer the thought of higher capacity. I totally understand your decisions. But let’s not bash any superior round because you prematurely decided on a specific one. There’s nothing wrong with 9mm it’s awesome, but let’s be clear… it isn’t equal to 357 Sig and the few extra rounds it’s capable of holding in a magazine over 357 Sig definitely doesn’t make it the superior choice. In time I expect 357 Sig to make the comeback that 10mm has made in recent years… For myself these 357 Sig advantages make 9mm less desirable. How about for you?

I converted my 9 mm to 357 . I do prefer my P229 in 357 over the 320 because you don’t feel the recoil as much. 357 is a much superior round regardless of what anyone says.

I like the X module but in the carry size. In black.

Love my 229 in 357 Sig. ammo is now super expensive. It’s a 40 now

You want .40 s&w, just swap the barrel with this conversion kit.

imagine just buying another module boom 2 guns

Very cool. Congrats

Man if you had bought this conversion kit a year ago you would have vans able to find more .357 sig that you could use. And it was cheaper than 9mm. I picked up a couple thousand rounds of American eagle .357 sig for $11.00 per 50 from a website that no longer has any .

Personally I’d keep the compact module and shoot +P 9mm in it which get you close to .357 Sig. But the .357 Sig is a cool caliber and definitely worthy of conceal carry.

Wait so you can’t just swap the barrel instead taking out the trigger

have a link to the conversation kit

I personally carry a P320 Compact with 135g +P rounds, not as cool as the 357 but i'm close enough

The only issue is these kits cost almost the same as just buying the 40 or 357. I saw these kits and in my opinion they’re a rip off cost wise.

Where you buy a convertion kit?

Any website that sends you the FCU straight to your house ?

That conversation put together look like it will Definitely jam

I'd rather buy a new P320 in .357 rather then pay over $450 to be able to interchange it with my other P320......

Sig P320 this is the Gun that goes off on it's own. Sig Sauer has Multiple Law Suits. New Trigger or Old Trigger still blowing holes in legs of people who carry these weapons.