9mm SBR question

[Laidback]

Looking to build 9mm SBR now...I know bad timing. Anywho, I am trying to figure out if I need to get a lower parts kit with a hammer specifically for 9mm or not?
I was also looking at a CMMG Product Number: 55BA127-L stripped upper with left side ejection for 9mm/22. Their customer service said that is would work for my build and they are even in stock. I just want to know if anyone has advise or experience with this upper. I just need the dust cover and brass shield for 9mm build. Any leads on those either. Also, first build so ANY help is appreciated. I do have a few friends helping out but the more knowledge the better.
Thanks in advance!

 

[ORD]

Re: 9mm SBR question

The hammer you need will depend entirely on which 9mm bolt/carrier you run. If you can get a CMMG 9mm bolt/carrier (the best in the business in my opinion and experience and all that I use for my own builds and any I help others put together), you can run any standard AR-15 hammer without modification. The CMMG units are "ramped" from the factory and don't require use of the @#$% 9mm specific hammer. This is my recommendation to anyone building a 9mm AR because it means one less @#$%ing non-standard part that you have to use (and less headaches for finding replacement hammers later should you break one, etc.). Also, if you can't get a CMMG 9mm bolt/carrier, then you can get any other 9mm carrier (such as an RRA for one example) ramped by the fine folks at ADCO. This is a gunsmithing service that they offer for fairly cheap and that too will let you use any standard AR hammer.

As for the CMMG modular/"Revolution" uppers...I have not used one, but if CMMG says they'll work for your build, I would have no qualms about trusting their opinion. I personally have no need for the modular upper nor would I want the left-handed eject. I personally would just opt for the CMMG Mk9 upper (or similar alternative), but that's just me. Also, you can use any standard AR upper for a 9mm build too provided you run the 9mm ejection port door and deflector.

As for finding parts for your 9mm SBR build right now...good luck. You just have to keep a watchful eye and be quick on the clicker when you find them in stock. You found CMMG obviously and they are a good source as are any dealers that stock their parts/firearms/etc. Also try the BARFCOM EE, GunBroker, etc., etc. Beggars can't be choosers at this point in time or you will have be patiently wait out the crazies for parts to creep back into stock.

Good luck!

 

[Laidback]

Re: 9mm SBR question

ORD,
I saw that CMMG and YHM had the "ramped" feature. So that will be good to have two things to look for.
As far as the left eject, I am left handed. I had given up on the left handed eject thing due to seeing a few things that looked like it was going to be a pain in the but to try to find in "left handed" all the time. As far as I can tell so far, the only things I know that I could build as ambidextrous is the safety, mag release and charging bolt.
I want to do a 7.5" barrel and suppressor for this one so trying to find that in stock and built at any kind of decent price just ain't happening. Plus, I love to know how things work and how to build it so I think it will be really fun. Hoping to find 7.62 lower to hold onto until I can do the next build.

 

[Laidback]

Re: 9mm SBR question

oh ya, what is barfcom? just looks funny.

 

[ORD]

Re: 9mm SBR question

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Laidback</div><div class="ubbcode-body">oh ya, what is barfcom? just looks funny. </div></div>

Ha, ha! AR15.com (affectionately referred to by many as BARFCOM). They have a HUGE equipment exchange (EE) section over there with all manner of AR parts, accessories, etc., etc., etc. I don't spend any time any more in the "technical" side of the site with a few exceptions like the industry forums, but the EE is a good place for commerce (just be prepared for the sticker shock right now on most things).

 

[ORD]

Re: 9mm SBR question

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Laidback</div><div class="ubbcode-body">oh ya, what is barfcom? just looks funny. </div></div>

Ha, ha! AR15.com (affectionately referred to by many as BARFCOM). They have a HUGE equipment exchange (EE) section over there with all manner of AR parts, accessories, etc., etc., etc. I don't spend any time any more in the "technical" side of the site with a few exceptions like the industry forums, but the EE is a good place for commerce (just be prepared for the sticker shock right now on most things).

 

[Laidback]

Re: 9mm SBR question

On the upper by CMMG: it comes as a base and then you add the two sides that you want...not too sure about having the upper as 3 parts. If I use a standard AR15 Upper receiver will that do fine for the 9mm? Also, if that works, how big of a pain in the butt would it be to just change out barrels if I wanted to shoot .223? Just trying to weigh my options out with what is available out there.

 

[ORD]

Re: 9mm SBR question

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Laidback</div><div class="ubbcode-body">If I use a standard AR15 Upper receiver will that do fine for the 9mm? Also, if that works, how big of a pain in the butt would it be to just change out barrels if I wanted to shoot .223? Just trying to weigh my options out with what is available out there. </div></div>

As I said before...you can run a standard AR upper for a 9mm built using the 9mm ejection port door and deflector (or just the basic AR, but the gas blowback without the deflector can be brutal...especially on an SBR 9mm. Remember...no gas system...it is ALL blowback with a 9mm. Unless you run a lefty upper though since you'll be shooting left-handed...the blowback won't be too big an issue).

As for the "ease" of switching calibers...it depends on the tools available to you and your mechanical inclination. Barrel swaps, upper builds, etc., can be done by the average Joe with the proper tools and some time. BUT...it isn't just a matter of switching your barrel. With a .223, you'll also need a gas system and other parts for the conversion, including gas block, tube, 223 BCG, mags, removal of your 9mm mag block, etc.).

 

[Ajax2112]

Re: 9mm SBR question

Here are some leads on parts.

CMMG 9MM BCG
http://www.cheaperthandirt.com/product/ARR-9441

I know it's not a 7.5 barrel but I don't think 1 inch difference is that much of a deal.
http://www.cmmginc.com/product_p/90d3b00.htm

As far as an upper if you don't mind an A2 upper I would check with Adco they have them in stock
http://www.adcofirearms.com/acc/ProductL...per%20Receivers

I hope this helps.

 

[Laidback]

Re: 9mm SBR question

ORD,
Not sure how I missed that before. Probably has something to do with the 15 or so internet tabs open looking for stuff. I am pretty handy but all that sounds like a big PITA. I like the idea of removing two pins and swapping bolts a lot better to switch calibers.
The blow back factor may steer me to the left hand eject CMMG parts. AND they are available from CMMG with no stupid prices.
Thanks!

 

[Laidback]

Re: 9mm SBR question

Ajax,
Thanks for the leads!

 

[Laidback]

Re: 9mm SBR question

Ever hear anything about Double Diamond Barrels? trying to find 5 1/2" ish length barrel. I forgot about the 3 lug adapter and mount that will add a little length to the overall.