5.7 SBR build

[reckless1911]

Im looking to do 5.7 SBR build but was only able to find an 8inch barrel. I was wondering if there was any particular stock/buffer tube set up or addictions other than a suppressor that I could possibly get that which would increase the overall length to the MD requirement? or am I better off just scrapping the SBR idea and building it as a standard 16inch barrel carbine?

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[outrider58]

Looks like you'll have about 2.5" +/- to make up.

Look for extended length buffer tubes, LAW type buffer tube folders(yes, they are legal in Md), as well as extended thickness butt pads(see Magpul). Also, if you are going to suppress it, will there be a QD muzzle device for your choice in a suppressor that can be pinned and welded on?

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[smdub]

Once you get up to 8" or longer might as well get an AR57 upper. Thats about the shortest barrel that still clears their handguard. Gets you 50rds of FN mag goodness!

You could also cut down a 16" AR57 to 10" (or whatever you'd need to make MD length)

 

[rsideout]

This is essentially my build from many years ago. AR57. The barrel is 6". The suppressor that I use sticks out about 3 inches beyond the handguard, but it was purpose built for this platform and is pretty efficient. And the 50 round PS90 mags are flawless.

 

[outrider58]

CMMG makes a 40 round vertical conversion mag

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[Baldheaded]

I really like the 5.7 caliper. I have an FN57. It is nice but I have been thinking of maybe selling it and getting the Ruger57. I just prefer rifles. The PS90 is to much $$$ and I don't know if it is really $700 better than the Ruger.

 

[outrider58]

This is essentially my build from many years ago. AR57. The barrel is 6". The suppressor that I use sticks out about 3 inches beyond the handguard, but it was purpose built for this platform and is pretty efficient.

...and a fun gun to shoot to boot! Very easy to control.

 

[reckless1911]

Once you get up to 8" or longer might as well get an AR57 upper. Thats about the shortest barrel that still clears their handguard. Gets you 50rds of FN mag goodness!

You could also cut down a 16" AR57 to 10" (or whatever you'd need to make MD length)

I like your Idea of buying the 16inch barrel and cutting it down but is it worth the cost to to do all of the custom work vs this $999 fully complete 16inch upper?

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[outrider58]

I like your Idea of buying the 16inch barrel and cutting it down but is it worth the cost to to do all of the custom work vs this $999 fully complete 16inch upper?

UPPER GROUP, RESOLUTE, 5.7X28MM, 16.1" | CMMG - AR 15 and AR 10 Builds and Parts

Personal defense calibers like 5.7x28mm have become a big thing in the last few years, and if you’re looking for P

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Thought you wanted an SBR.

 

[smdub]

^This. Thought you wanted an SBR.

Looks like they even make an AR57 in 12" now (they didn't back when I ordered mine.) On sale for $650.

https://palmettostatearmory.com/panzer-ar57-ult-upper-assembly-5-7x28mm-12-ar57ult-12.html

 

[reckless1911]

^This. Thought you wanted an SBR.

Looks like they even make an AR57 in 12" now (they didn't back when I ordered mine.) On sale for $650.

https://palmettostatearmory.com/panzer-ar57-ult-upper-assembly-5-7x28mm-12-ar57ult-12.html

Your right I did.. I just started adding up all the cost in my head and got deterred. But I'm back on track.. I think I will just take my time and go the route of getting the 16inch barrel cut down like 11inch with a suppressor QD muzzle mounted and folding stock. Just need to find a gun smith who can do the barrel work.


I would buy a complete upper but I wanted to go the CMMG 5.7 route to custom build cause im trying to add more color to my collection for my last builds. I want to do the 5.7 in bronze since im also going to build out a PSA Jakl SBR in FDE and a Aero 22 inch 6.5 creedmore in FDE.

Shoot now that im even typing this I'm thinking I might as well get another Aero M5 lower to and make an SBR .308 cutting down their 16inch barrel too since im going to be in a gun smith & Form 1 submitting mode lol.

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[smdub]

Its easy to cerakote an AR57 upper in a different color

I wouldn't cut down an AR10 barrel. Its not blowback, so where the gas system ends up relative to the barrel length is important. FAR easier and cheaper to just buy the correct length barrel.

 

[smdub]

Before you order that CMMG 16" upper, notice that the muzzle end flares out in diameter for the brake. That will be gone if you cut it down. Maybe not much of a shoulder left to work with for the muzzle device once you rethread. You can't cut every barrel down. Need to know the barrel diameter where you are going to cut it and compute if there will be enough shoulder left.

 

[rondon600]

Palmetto has FN ps90 on sale for $1700 with 2 mags and a vortex red dot. Wish I had bought one years ago rather than the ar57 upper. Still neat though.

 

[reckless1911]

Before you order that CMMG 16" upper, notice that the muzzle end flares out in diameter for the brake. That will be gone if you cut it down. Maybe not much of a shoulder left to work with for the muzzle device once you rethread. You can't cut every barrel down. Need to know the barrel diameter where you are going to cut it and compute if there will be enough shoulder left.

yea I noticed that too... Ok then back to the 8" barrel with QD muzzle, Folding stock and 7 position tube. I will just put in for a short dedicated suppressor for my 5.7s and 9mms and just use my Silencerco Hydrid 46 whenever i take it out the house until I get the shorter suppressor

 

[smdub]

Didn't say its not possible but you'd need to figure out the diameter in the middle there to see if its enough.

I wish I bought and SBRed a PS90 before the 2012 length laws hit. 'the one that got away'.

 

[reckless1911]

Didn't say its not possible but you'd need to figure out the diameter in the middle there to see if its enough.

I wish I bought and SBRed a PS90 before the 2012 length laws hit. 'the one that got away'.

Ok so back to cutting down the barrel. Spoke to Aero and they said that the 7.3 hand guard i needed is probably not going to come back in stock. So cutting down to 10.5 and getting the 10.3 hand guard is my best option (Only because I want this color for my build).

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[reckless1911]

does anyone know a good source for getting the barrel cut down done? just ordered my receivers/ 10inch hand guard so I'm ready to order the 16inch barrel and get it worked down to 10.5

 

[Growler215]

Make a "braced pistol" with an SBA4 using your 8" barrel? Maryland still considers them to be pistols, so don't need 29" and right now it doesn't matter what the ATF considers them to be, but you can go ahead and register it as an SBR if you want, but leave the brace on to keep MD happy.

 

[reckless1911]

does anyone know a good source for getting the barrel cut down done? just ordered my receivers/ 10inch hand guard so I'm ready to order the 16inch barrel and get it worked down to 10.5

Unfortunately Aero doesn't have the the matching color hand guard in stock in 7inch for the FDE Bronze receivers I ordered and after speaking to them was told its unknown if or when they will restock so I had to buy the 10.3 just to be safe. In the time I can wait a couple months to see if it pops back up in 7inch before buying the barrel, I can just submit the eform and let it sit while I work on other stuff. Just want to find someone now who can do the barrel work. But damn your idea makes hella sense and would be much simpler if I can live with switching colors... I will just wait a couple months tho and cross my fingers the 7inch comes in stock