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How to Select the right parts for your AR Upper Build

Posted by Jose Rueda on

Welcome to our AR Build tips page. Today we are go to cover how to select the right parts in order to build a proper upper. First you will need to decide what kind of upper you would like to build. Keep in mind what you will be using it for. If your building a first upper the key is to always keep it simple. Make sure that you stick to mil spec setups, once your rifle works properly then you can start adding your hopped up parts one by one.

I will setup a quick guide that will allow you to pick out the parts you will need for an upper build, add to your cart, and then apply the ARBUILD discount code and have us build it for you, test fire and ship to you. let's get started


1. Select an Upper

You will need to select an upper receiver HERE, both styles function the same... the ultralight shaves a few ounces off the weight which helps when building an ultra light weapon system for competition. Many opt for the lighter weight receiver, that has the added benefit of saving money due to less moving parts and labor involved. Pick a receiver add it to cart and move to the next step



 2. Select a Barrel

Next you will need to Select a barrel HERE. You will need to make a decision on what caliber and length you would like to build your upper. For beginners stick to a .223/5.56 or Wylde Chamber, these are the most common and are the easiest to shoot in the AR-15 platform. For more advanced shooters you know what you want just make sure you take note of the gas system of the barrel so you can select the proper gas tube for your build. You will be looking for the "Gas System" spec you will find the following common lengths: (Pistol, Carbine, Mid length, and Rifle Length)... 

3. Select the Gas System

After selecting the barrel you will need Select a gas Block HERE then select the corresponding gas tube length hereThe gas block should be .750 for most of our barrels, if a larger diameter is needed the barrel will specify that for you. The gas tube is the length at which the gas port is drilled on your barrel, most pistol barrel 7-10" use a pistol gas length, the next largest is carbine usually used in 10-16" barrels, then mid length used in 16-18", and finally rifle length used on barrels from 16-24". make sure you choose the correct one. If we are buidling your upper for you then we will double check and make sure you chose the correct gas tube...

4. Select the Hand Guard

Once you have your receiver and barrel selected you will then need to Select the Hand Guard HERE.  Choosing the handguard is one of the easiest ways to customize your rifle. When choosing the right hand guard take time to look forward, how will you use your rifle in the future? You can chose between a variety of lengths and styles. What accessories do you plan on attaching to your personalized rifle today or in the future, selecting the right hand guard could make the difference in what will or will not attach to your rifle down the road. All of our Hand Guards offer full featured ergonomics and performance and offer a wide range of selection from 3-Gun setups to Ultra light Carbon fiber setups. Browse our large selection of hand guards to find the best fit for you.

5. Select the Muzzle Device

Finally you will need to Select the Muzzle Device HERE (Brake) . The muzzle device must fit your barrel. in this section on the left hand side (or up top in mobile) you can filter the products that will work for your barrel. We suggest filtering by Caliber, this ensures that the muzzle brake you select will fit your barrel for the build. For beginners, as a rule of thumb, you would want a "Can Style, or Linear Style" Brake for short barreled uppers in 7-12" length.  For competitive use we recommend the Titan series brakes. for tactical and all around use you may want to go with a Shark or Battle port style brake. Again browse our selection and see if there is one that best suits the look you are going for.  


6. Adding the Discount and FREE building service.

Now that you have all the minimum item in your cart it is time to apply a very special Discount to maximize your dollar purchasing power! We are now offering 33% off any upper build you put in your cart today and we will build it for free!  Please use code: "ARBUILD"  use this code to get a HUGE discount on all the parts in your cart.

This Discount will apply to any Cobratac/Black Label items in your cart, so if you see things that you would like to include in your order add them now to get the discount. We will build your upper and ship it within 1-2 business days (if you add items that are other than Cobratac/Black Label there will be an extra 2-3 biz days to have those special order items come in for the build.

Enjoy your shopping Experience and your brand new fully custom and tested upper!

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  • 27 January 2018. Good morning gentlemen. I designed “TOR” PCC Upper different than any AR-15 or others in today´s market. I am interested in a carbon fiber OEM propietary model for “TOR” which would have different external width and lenght to current models.
    Advancve thanks for your reply with any questions or suggestions. Best regards from, Fernán A. Febres, Armament Systems Engineer, President Modern Defesne Corporation.

    Fernán A. Febres on
  • John Hirst why don’t you start a support ticket and see if we can help you out in a PM

  • Im looking for an unfinished alluminum stock to put on my existing milspec buffer tub on my AR. Can you provide this for me? I will pay the regular price for it as if it were coated. Please let me know. Thanks

    John Hirst on

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