Gunsmithing Who could build a MSAR STG 556 barrel in 300BLK?

[b0xcrash]

Is chambering a MSAR STG 556 in 300 AAC possible?

How hard is it to build a 16" barrel for a STG 556 in 300 BLK?
And if it can be done, who could do it?

The other issue might be gas system. Talked to Ratworx and they seem to think it would be a nightmare, to quote them.
..but I could not get any explanation on why.
What about the gas system that makes it a nightmare, besides it is integrated and they said something about the port is in the wrong place?!?!?

The gas piston can be removed...what about purchasing a replacement gas piston and then machining it to open it up or whatever would need to be done to it to allow this?

To me the biggest challenge seems to be finding a replacement barrel assembly.

I do not fully understand the differences in the gas system, but a little perplexed how the AR platforms are able to accomplish 300 BLK with a barrel swap? But the STG firing the same 556 cannot?

 

[Wolvenhaven]

Re: Chamber a MSAR STG 556 in 300BLK?

You do realize the barrel's inner diameter is completely different between the two rounds right? You can't exactly chamber a .223 barrel with a .300blk reamer and get a working barrel. You have to use a .30cal barrel to begin with.

 

[b0xcrash]

Re: Chamber a MSAR STG 556 in 300BLK?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Wolvenhaven</div><div class="ubbcode-body">You do realize the barrel's inner diameter is completely different between the two rounds right? You can't exactly chamber a .223 barrel with a .300blk reamer and get a working barrel. You have to use a .30cal barrel to begin with.</div></div>

Yep. I did not know that but I do now thanks to the shout box and your reply.
Sorry I am new at this so what you would call stupid

So I could probably have a good smith make a barrel from a .30 cal and machine the same star as the barrels that come in the STG, then figure out the mounting plate, catch and foregrip.

Then no idea about the gas system, but if a stock AR can handle it, I would think the gas system should too.

 

[Mike_in_FL]

Re: Chamber a MSAR STG 556 in 300BLK?

The fact is MSAR is out of business. Unfortunately that means you're going to see no new barrels nor calibers unless somebody decides to pick up and start remaking these rifles.

I think you'd better research what you said in your initial post. How does this caliber work by changing a barrel on an AR? Is the AR using a DI gas system or a piston? Unless you're capable of redesigning the gas system on the MSAR I think you're going to possibly be wasting a lot of $ and possibly ruining your rifle. Ratworx is probably the ONLY currently existing experts on this rifle. Why are you so quick to disregard what they've told you?

Oh btw, have you added in the cost of replacing parts that might get broken in this experiment? It's not like you can call the factory and get a replacement anymore so I hope you know a good AND cheap machinist.

You need to put down what costs you KNOW. Whether this be from gunsmiths's estimates or whatever. Then figure what an AR in this caliber would cost you.

 

[2156SMK]

Re: Chamber a MSAR STG 556 in 300BLK?

The reason the 300 blackout/whisper can work on the AR is that there are many different length of gas systems.

Read my gas system write up for a better explanation:
www.ar15barrels.com/prod/operation.shtml

The amount of pressure available at the longer gas port position of the AUG would most likely not be enough to make the gun function without significant changes to the design.

 

[b0xcrash]

Re: Chamber a MSAR STG 556 in 300BLK?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 2156SMK</div><div class="ubbcode-body">The reason the 300 blackout/whisper can work on the AR is that there are many different length of gas systems.

Read my gas system write up for a better explanation:
www.ar15barrels.com/prod/operation.shtml

The amount of pressure available at the longer gas port position of the AUG would most likely not be enough to make the gun function without significant changes to the design.</div></div>

thanks.that makes sense.....so the port is in the wrong place and awesome write up. crash course on the gas system helps