Hello All-
First off, I tried the search button but it came back with a million pages and after checking the first 50 pages I figured I'd just ask the questions. Secondly, I put this in the AAC section because it is their suppressor I will be using and figured AAC would have the best answers. If this should've went somewhere else, my apologies, and please feel free to move it.
I just purchased an AAC M42000 5.56mm suppressor and am waiting for ATF approval. This gives me time to put together the next step...
I want to put it on an AR15 SBR (10.5" barrel). I would also like to use the SBR without the suppressor, at times. I want 100% reliability from the rifle at all times (is that possible). Is there anything I need to do with the SBR to achieve this (adjustable gas block, special buffer/spring, etc)??
To compound my questions more, should I convert my existing 16" AR15 to an SBR, or buy an SBR direct from the factory so it is already set up as a working SBR?? And if purchasing a rifle from the manufacturer, is there a certain mil-spec manufacturer that puts out SBR's that work 100% of the time with and without suppressors attached?? My current rifle is an LWRC M6. Should I stick with a piston gun or go with a DI?? I don't have a problem buying a completely new rifle if it will achieve the 100% reliability requirement (Buy Once-Cry Once).
I know countless others have been in this situation and have had to learn things the hard way. I'm trying to get it right the first time and thought I'd ask the experts here your opinions since you all know way more about this than I do.
Any assistance is appreciated. Thank-you.
Tim
100% Reliability running M42000 on SBR Question
Moderator: SilentMike
Re: 100% Reliability running M42000 on SBR Question
In regards to your first question is the SBR upper a factory upper (if so from whom) or did you build it?
Re: 100% Reliability running M42000 on SBR Question
Let me clarify... I don't have the SBR yet. I'm looking for advice on what to get.
Re: 100% Reliability running M42000 on SBR Question
AR15’s consists of an upper and a lower (you already know this but using this as a starter). If you were to go the factory upper route and were looking in the 10.3-10.5-inch range, I would look at either the LMT 10.5" M4 Carbine Upper Receiver Group or the Daniel Defense MK18. Noveske also makes a Shorty Basic Upper with a 10.5" Barrel. All those are going to run and be a buy once cry once purchase. There are also a number of good options in the 11.5-inch range if you wanted to add an inch. There are those that say an 11.5 is a better options as you get better velocity and longer dwell time.
You could also build one yourself, one with the rail you want, the barrel you want, etc. If you don’t have the experience or the tools you can have a competent gunsmith assemble it for you as long as you have all the parts for around $100. Advantage of the factory build is if you ever have issues you can call up the company and put in a warranty claim. All three companies I have listed above have excellent customer service.
In regards to the purchasing the whole gun. Sometimes it's nice to get a factory SBR. There is no engraving on the lower, the gun was built as a whole, the warranty is over the upper and lower. If you have any issues the company (as long as they are reputable) has got you covered. At the same time, you might have a lower you like and would want certain components you would start out with that will save you a little money. In that case building the lower is the way to go. One is a form 1 and one is a form 4 from an NFA perspective. A factory SBR is still an SBR lower and you can put other shorty uppers on it.
Either way, as long as they are quality components and put together by a someone that know what they are doing you should be good to go.
Running the gun with a can – you shouldn't have any issues. Generally the only thing that needs tweaking is the buffer as you may have to go from an H1 or H2 to an H3 depending on the can but that's easy.
You could also build one yourself, one with the rail you want, the barrel you want, etc. If you don’t have the experience or the tools you can have a competent gunsmith assemble it for you as long as you have all the parts for around $100. Advantage of the factory build is if you ever have issues you can call up the company and put in a warranty claim. All three companies I have listed above have excellent customer service.
In regards to the purchasing the whole gun. Sometimes it's nice to get a factory SBR. There is no engraving on the lower, the gun was built as a whole, the warranty is over the upper and lower. If you have any issues the company (as long as they are reputable) has got you covered. At the same time, you might have a lower you like and would want certain components you would start out with that will save you a little money. In that case building the lower is the way to go. One is a form 1 and one is a form 4 from an NFA perspective. A factory SBR is still an SBR lower and you can put other shorty uppers on it.
Either way, as long as they are quality components and put together by a someone that know what they are doing you should be good to go.
Running the gun with a can – you shouldn't have any issues. Generally the only thing that needs tweaking is the buffer as you may have to go from an H1 or H2 to an H3 depending on the can but that's easy.
Re: 100% Reliability running M42000 on SBR Question
The Monk- Thank-you, sir. That was extremely informative and I appreciate the info. I think I'm going to buy from the factory. I'm undecided right now if I'll buy a complete SBR or just get an upper, but I'm thinking that factory built is the way to go (warranty, etc).
As for the upper, I've heard about needing an adjustable gas block to fire the weapon reliably with and without the can. Has that also been your experience or do the options you've listed work just fine without such device?? I saw Noveske has a complete SBR with a switchblock, but is that really needed, or is it a marketing gimmick?? I can't tell if LMT or DD SBR's have them or not.
As for the upper, I've heard about needing an adjustable gas block to fire the weapon reliably with and without the can. Has that also been your experience or do the options you've listed work just fine without such device?? I saw Noveske has a complete SBR with a switchblock, but is that really needed, or is it a marketing gimmick?? I can't tell if LMT or DD SBR's have them or not.
Re: 100% Reliability running M42000 on SBR Question
The main problem you get when suppressing an AR is gas to the face. This is caused by too much gas in the system that will vent in any way possible. A lot of that will blow back through the charging handle.
An adjustable gas block allows you to turn down the gas level just to the point of making the rifle function. If you were to run it without a can with the gas turned down the rifle wont function as there wont be enough gas. The Noveske switchblock is a great easy way to turn down your gas. it does limit rail selection though - no free lunch with this stuff. This doesn't really have to do with reliability, more with comfort.
Gemtech has a bolt carrier that allows you to turn the system to suppressed and it will vent all extra gas out the side. This is a good review - https://youtu.be/TJnXyd-JC1E. I am in the process of getting my hands on one of these but I have only heard good things. M4 Carbine has a lot of data on suppressing a 556 ar.
An adjustable gas block allows you to turn down the gas level just to the point of making the rifle function. If you were to run it without a can with the gas turned down the rifle wont function as there wont be enough gas. The Noveske switchblock is a great easy way to turn down your gas. it does limit rail selection though - no free lunch with this stuff. This doesn't really have to do with reliability, more with comfort.
Gemtech has a bolt carrier that allows you to turn the system to suppressed and it will vent all extra gas out the side. This is a good review - https://youtu.be/TJnXyd-JC1E. I am in the process of getting my hands on one of these but I have only heard good things. M4 Carbine has a lot of data on suppressing a 556 ar.