Dedicated Suppressed SBR *Does not function: Update Page 4*

[Iraqgunz]

JM2CW. If it were me, I would want my AR to function with or without a suppressor-regardless of what I was intending to do with it.

I would have the port opened up. Again, that's me.

I just got back from the range.

I brought Lake City M193, Federal XM855 and PMC Bronze .223.

I started out with an H2 buffer and Federal XM855.

The bolt carrier cycled enough to cock the hammer and eject the spent case but not enough to strip the next round.

I then switched to the H buffer with the same ammo, and the results were the same. I got the M193, and although the muzzle flash and flash was significantly more pronounced the rifle still didn't cycle. Casings would eject but the bolt would slam home on an empty chamber.

I tried a few rounds of PMC Bronze, but they wouldn't even eject the case and it would create a failure to eject jam in the upper, not stovepiping...almost like the bolt carrier stopped too far short and started to return home with the empty shell casing getting lodged in the barrel extension.

I am almost positive that my gas port size is ~.058" after experiencing this, and I am really looking forward to a smooth shooting suppressed rifle.

As I've said from the beginning, whether or not the rifle worked unsuppressed was irrelevant. Maybe in the future I will try an LMT enhanced carrier but for right now I have other uses for those funds.

...I just hope it functions suppressed. Anyone with experience want to chime in on their thoughts?

I did get my aimpoint and irons zero'd at 50 yards however so it wasn't a completely useless day.



The AAC Brake performed extremely well. There was no felt recoil or muzzle climb at all. I also did not feel any blast or concussion (and this is at an indoor range)...the design of the brake sends the blast off to 90* away from the muzzle. Probably why the guys in the lanes adjacent to me were not very happy



See above Very unpleasant, but surprisingly not so much for the shooter.

I will make the disclaimer that I normally wear foam ear plugs and today I was wearing the ear plugs and muffs I did not feel any concussion however.

[Eurodriver]

JM2CW. If it were me, I would want my AR to function with or without a suppressor-regardless of what I was intending to do with it.

I would have the port opened up. Again, that's me.

I agree. I am very practical when it comes to my firearms and having an AR that needs a suppressor mounted to work is the antithesis of that.

However, its a 10.3" barrel with a muzzle brake. I really can't see myself shooting it unsuppressed in any situation, you yourself advocate that friends don't let friends shoot unsuppressed . With that said, the capability would be nice and I may try getting an LMT enhanced carrier before I do anything to the gas port. Either way, I will wait until the suppressor gets in.

[C4IGrant]

What buffer spring are you using?


C4

[Eurodriver]

USGI/The spring LMT sells with their lowers.

[Todd.K]

If you could reliably get away with a smaller gas port size unsuppressed I would build all of them that way.

If you get it to just barely function at the range and then expect it will run you may end up in the cold, dirty, or under lubed and have it fail when it's needed.

[Eurodriver]

I understand.

I was not expecting this to run unsuppressed at all until I read this thread and his Colt 16" barrel cut to 10.3" works great with an H2 buffer.

This leads me to believe that Surf was right and the gas port on my DD barrel is .058"

[C4IGrant]

USGI/The spring LMT sells with their lowers.

Interesting. I would for sure check out the LMT Enhanced carrier. This is most likely the difference.


C4

[Iraqgunz]

That is more of a joke, than a philosophy as not everyone can buy a suppressor. Having said that using a suppressor in every situation may not be practical or possible.

I don't think that the carrier is going to help you and if it were me I would open the port up a little.

I agree. I am very practical when it comes to my firearms and having an AR that needs a suppressor mounted to work is the antithesis of that.

However, its a 10.3" barrel with a muzzle brake. I really can't see myself shooting it unsuppressed in any situation, you yourself advocate that friends don't let friends shoot unsuppressed . With that said, the capability would be nice and I may try getting an LMT enhanced carrier before I do anything to the gas port. Either way, I will wait until the suppressor gets in.

[Eurodriver]

That is more of a joke, than a philosophy as not everyone can buy a suppressor. Having said that using a suppressor in every situation may not be practical or possible.

I don't think that the carrier is going to help you and if it were me I would open the port up a little.

I spoke to Grant and when he gets back from training I am going to send my upper to him to tinker around with and get it to run unsuppressed.

After firing it, it really isn't loud enough to warrant complete non-functionality unsuppressed. Its quite tolerable for what it is.