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Sig M400 .300 Blackout barrel replacement
Wild Bill Dozer
Member Posts: 6 ✭
Does anyone know if I can simply swap out my .300 blackout barrel with a .556 barrel in my M400? Ammo is getting expensive. If so, can y’all recommend a good, inexpensive vendor?
Comments
Any AR barrel should work. Depending on the length of the current gas system you may need to get a new gas tube along with a new gas block to fit the diameter of the new barrel. Those parts won't break your piggybank. How much you decide to spend on a barrel depends on the strength of your wallet.
The best place- In fact the ONLY place to buy ammunition in the Gun Broker forums is...the GB auctions.
Sorry. I meant a vendor recommend to buy the barrel. I’m switching barrels because 556 is about 50% the cost of 300 blackout.
Would this one work? Would I need the gas tube? https://www.gunbroker.com/item/891286382
You need to determine if your present barrel has a carbine or pistol gas port/gas tube. You can google this and get the measurements. The barrel you linked is a carbine gas and many/most 300AAC barrels use pistol gas port location so I'm guessing that yes, you'd need a different tube.
Might be a bit more expensive, but you could just drop a new upper on it.