Billet vs. Forged Receivers for 6.5 Grendel Build

[RockyMountainJ]

I'm sure this has been beaten to death already on this forum, but I can't find any information in the search; so I'll ask again:

Are there any advantages or benefits to using a billet upper and lower for a 6.5 Grendel build? I'm planning to use a 20" bull barrel for my build. I already have a Spikes Tactical forged upper and lower on order, but have recently started looking at the billet receiver sets from Mega Arms and Spikes. They look nice, but are much more expensive! Again, other than aesthetics, is a billet receiver set going to add anything to a 6.5 build?

My rifle will be used for everything from hunting to 3-gun to paper punching.

Your advice is much appreciated!

[knappmenterprises]

My new grendel build is set on a billet lower (Saber tactical) and billet Mega upper with side charger. While I can't see any real gain from the billet lower other than looks, the mega billet upper SBU models are built like a tank. Way thicker walls and the machining and matchup is downright beautiful. Mega claims they are "great for long barrel applications" and although my build isn't completed, I am thoroughly convinced the extra strength of the billet upper can only add to rigidity along the entire rifle especially with a heavy and long bull barrel on it, getting a 24" myself. as for cost, the mega arms billet sbu uppers, either side charging or their other model with no forward assist or port cover can be had for less than 150 bucks online, in par with any decent brand forged upper.

[txgunner00]

Welcome to the both of ya'.

Billet receivers are said to be stiffer and more accurate but there a lot of tack drivers built on forged receivers. I don't know that there is any real advantage unless you are building a very high end rifle or have a long/ heavy barrel. It really depends on what you will be happy with and how much you want to spend IMO.

Good luck.

[LRRPF52]

Here is a general rule of thumb when I feel that a billet upper becomes more justified:

If using a bull barrel profile of significant weight, lean towards the billet upper.

If using a medium contour like .875" or smaller under the handguard, and a 20" length or smaller, a standard upper will be fine.

If I were building a bull-barreled Grendel or any other caliber AR15, I would most likely use a billet upper, with more mass to it. It's not an absolute, but I think it's good insurance to resist the increased mass of your pipe.

[COLDSTEEL77]

In my case i chose billet for accuracy. Rainier arms makes a ultra match billet upper that is precision machined with tolerances of .0003 which is the best ive found so far.

http://www.rainierarms.com/?page=shop/detail&product_id=1611

[Drifter]

Billet upper might also be more likely to have a correctly squared receiver face versus forged. I usually go with billet uppers and forged lowers, but there are some good quality forged upper receivers available. The Vltor MUR is one example.

[RockyMountainJ]

Thanks fellas. I'm leaning toward getting a Spikes billet upper to go with the forged lower I already have ordered. Since I'm planning to use a bull barrel, it seems as this is probably the safe way to go.

Do the billet uppers match up with the forged lowers very well, or is there a noticeable difference in the thickness of the metal?

[Zssc7]

I would say it wouldn't matter to much. The most important things when looking at having an accurate ar platform are the trigger group, the barrel, and having the barrel free floated. Having a good rigid upper is important for your optics but the grendel cartridge doesn't really impart a lot of recoil force to the reciver/optic like a larger cartridge would. I mean really all the preassure from firing a round is going to be contained in the chamber and not so much imparted to the receiver. I don't know though just my humble opinion, you should go with whatever gives you the warm and fuzzy.

[Bill Alexander]

Cantilever weight of the barrel is the problem, more than the recoil.

Billet allows flexibility to increase the sectional stiffness with heavier wall thicknesses compared to the forgings. But to provide durability the correct material is required as well.

[txgunner00]

Thanks fellas. I'm leaning toward getting a Spikes billet upper to go with the forged lower I already have ordered. Since I'm planning to use a bull barrel, it seems as this is probably the safe way to go.

Do the billet uppers match up with the forged lowers very well, or is there a noticeable difference in the thickness of the metal?

I have a Mega side charging on a Rock River lower and it fits perfectly.

[RangerRick]

I would imagine the side charging uppers would benefit from using the billet. There is a lot of material removed in that long slot, so that would help with the strength/stiffness.

RR

[txgunner00]

I would imagine the side charging uppers would benefit from using the billet. There is a lot of material removed in that long slot, so that would help with the strength/stiffness.

RR

True. That's exactly why I chose billet in this case. All my other ARs are forged and I have one in particular that shoots just as good as the billet.

[RockyMountainJ]

I just received this back from Spikes Tactical when inquiring which was a stronger and stiffer receiver between forged and billet uppers:

"The barrel extension area cannot be any stronger than forged since that area has to be the same dimensions on any AR upper receiver. If the dimensions there were beefed up, it would prevent barrel nuts to thread or barrel extensions to slide in. That joint is the weakest spot on an AR.

What is better than that for heavy, long bull barrels in that use would be monolithic uppers that do not have a thin extension socket."

Do you guys agree with this assessment? If not, then what is Spikes missing here?

[LRRPF52]

"The barrel extension area cannot be any stronger than forged since that area has to be the same dimensions on any AR upper receiver. If the dimensions there were beefed up, it would prevent barrel nuts to thread or barrel extensions to slide in. That joint is the weakest spot on an AR.

What is better than that for heavy, long bull barrels in that use would be monolithic uppers that do not have a thin extension socket."

I can see where they're coming from, but I'm not sure if it plays out in the real world, since I've seen plenty of precision AR's that shoot phenomenally well (1/3 MOA or better). Many of those have had a beefier upper. There are a few members here that have built Mega Monolithic guns, so it would be interesting to hear their accuracy experiences, since most-if not all-have used high-end barrels with those builds.

Spike's sells billet receivers too.