Building an AR or AK thread

[PieOats]

Originally Posted by Topgunben [You must be logged in to view images. Log in or Register.]

https://www.80lowerjig.com/blogs/80-...th-twist-rate/

Should I be pushing for a 16 inch barrel or does it matter all that much? What issues will I run into if I go smaller than that? It gets treated as a pistol???

If barrel length is less than 16”, then you have to either build the weapon as a pistol (no buttstock, no vertical foregrips, maximum pull length from end of brace to trigger of 13.5”) or submit an application and $200 fee to the ATF for an SBR tax stamp. Keep in mind that if you neglect one of the pistol rules ad accidentally end up with an SBR, you could face 10 years in prison and $250,000 fine, so make sure that you understand what is and is not allowed on pistols, or just get a tax stamp and be free to do what you want with it.

The downside of an SBR is that it cannot be concealed and as a rifle is treated as such for all other state and local laws. SBRs are generally subject to additional state laws beyond ordinary rifles too. Also, for SBRs, the tax stamp means that you are the only person authorized to store, possess or transport the weapon. You can get around this by setting up a gun trust, donating the weapon to the trust and designating family/friends as trustees/beneficiaries. They are cheap and easy to setup.

[PieOats]

Also, you linked to 80lower. 80% lowers are not legal in some states and subject to additional regulation in some others, so keep that in mind. You can still build a firearm using an ordinary serialized lower though if you happen to live in one of those jurisdictions.

[Bardp1999]

This thread smells like Waco, TX. C U on Hale Bob REAL SOON

[Googi]

Sorry you cant legally pack in your state bard p1999 consider moving to the south asap

[Topgunben]

Originally Posted by PieOats [You must be logged in to view images. Log in or Register.]

Also, you linked to 80lower. 80% lowers are not legal in some states and subject to additional regulation in some others, so keep that in mind. You can still build a firearm using an ordinary serialized lower though if you happen to live in one of those jurisdictions.

For some reason that link isn’t working now, but the site more or less gave a breakdown of muzzle velocity compared to Barrel length. It seems that the sweet spot is right around 16 inches, anything longer seems to cumbersome, anything shorter causes loss in velocity.

That said, most of these AR kits are advertised as 16 inchers but the barrels themselves are only 13.5 plus a muzzle break. I imagine that a 2.5 inch muzzle break isn’t going to add to velocity the same as another 2.5 inches of rifled barrel.

What have you guys found is a decent barrel length? Is 16+ too cumbersome?

PS. I’m not planning on buying an 80% lower. By the time I mill everything out and get the jig to do it, I’d be spending more time and money then if I bought a 100%. I don’t like the idea of the Gov knowing I have one, but at this point, there are so many ARs in circulation, I have a hard time believing they will ever ban them.

[Spergand]

The government has no power over you its the people around you

[Spergand]

I bet kyle had a 16" barrel fwiw

[Googi]

Even if they did ban them, they will be around until they rust out, and its not like theres no gun smuggling now for illegal weapons?

[Spergand]

Aluminum doesnt rustand a retard could mill a lower from a chunk of aluminum if he wanted to, there not going anywhere. America is armed to the teeth it's really our best asset

[PieOats]

Originally Posted by Topgunben [You must be logged in to view images. Log in or Register.]

For some reason that link isn’t working now, but the site more or less gave a breakdown of muzzle velocity compared to Barrel length. It seems that the sweet spot is right around 16 inches, anything longer seems to cumbersome, anything shorter causes loss in velocity.

That said, most of these AR kits are advertised as 16 inchers but the barrels themselves are only 13.5 plus a muzzle break. I imagine that a 2.5 inch muzzle break isn’t going to add to velocity the same as another 2.5 inches of rifled barrel.

What have you guys found is a decent barrel length? Is 16+ too cumbersome?

PS. I’m not planning on buying an 80% lower. By the time I mill everything out and get the jig to do it, I’d be spending more time and money then if I bought a 100%. I don’t like the idea of the Gov knowing I have one, but at this point, there are so many ARs in circulation, I have a hard time believing they will ever ban them.

Oh okay, good deal. I just saw the web address had 80lower in it and didn’t follow the link.

As far as the 16” barrel goes, it all depends on what you plan to do with it. If you want the best accuracy to range ratio, you can go with an 18”. Anymore than that and you will end up with more whip. The only reasons to go shorter than 16” are if you plan to keep it for self-defense and would like something suited to CQB, or if you would like to suppress it, or if you want something easier to transport or have a CPL and would like to carry concealed. The one other consideration on barrel length is that if you build a pistol first, then you can convert it to a rifle whenever you like, but if your build starts as a rifle, then you cannot convert to a pistol. The likelihood of anybody ever actually knowing is small, but it is the law.

As for the 14.5” barrel, that would mean that you are either building an SBR or a pistol, unless you permanently affix the muzzle device by weld, solder or pin. The muzzle device cannot be removable, otherwise once you attach a stock to the weapon, you suddenly have an SBR, which requires the aforementioned tax stamp prior to assembly. The alternative of course is to build it as a pistol. If you do not want a pistol or an SBR and you want to be able to swap out muzzle devices, then go with an actual barrel length of 16” or more. Often they come in 16.1”