Billet vs Forged Recievers

[USMCSgt85]

I am now out on my first build and have a Shilen 20" heavy H-Bar barrel to start with. I have spent hours reading recommendations for different parts for builds. My question is which receiver is better a billet or forged? Having been a machinest for 38 years I know forgings have a denser material pattern because of the compression of forming where as billet grain of the metal is aligned with the extrusion direction of the billet. I want a tough reliable reciever that I can get the best accuracy out of. I have a RRA National Match mouse gun that prints right around 3/4" to 1/2" MOA and it sports a forged reciever, what are your ideas on this?

[cory]

Upper Receiver
For longer than 20" and a heavy 20", I'll always go with a billet. Anything shorter and lighter and I'll go with forged for the weight savings.

Steel (forged) is obviously stronger than aluminum(billet), so mass being equal the forged receiver will be the stronger receiver. With the billet receivers, they're (normally) beefed up in critical stress locations. This makes the billet the stronger receiver in terms of handling the stress the barrel puts on the receiver. There are other factors, as it appears you understand, but that gets a little more complicated and ultimately leads us to the same conclusion.

Lower Receiver
Unless it's a dedicated bench gun, I'll go with a quality named forged lower. I don't think the weight penalty of using the billet is worth the improvement in accuracy, which I believe to be minimal.

Semper Fi

[lead chucker]

I totally agree with Cory. But I'd go forged for both upper and lower. For both strength and weight. I have a billet side charged upper on a 18" Grendel and its heavy, I wish I had went with a forged. The rest of my ARs all have forged receivers.

[VASCAR2]

I'm using a forged PSA upper with my Shilen 20" 6.5 Grendel barrel I got from Midway. The front of the PSA receiver was square and my Shilen will give MOA or better out to 880 yards with my handloads. I'm sure a better shot could get more accuracy out of my Shilen. I used a PSA lower with RRA NM LPK and 6 position PSA stock. The Shilen barrel is the match unthreaded barrel and it balances well for me.

[am4966]

Upper I would go with a Vltor MUR it's a forged upper that is beefed up. You can find them for 165.00 with forward assist and cheaper without forward assist.

Lower Im going forged, no reason for billet.

If a lite weight barrel 18" and under forged. I had a billet set to use on a sbr had the upper lower together minus barrel, bolt rail and optic and it was heavy. Sold the billet set and went forged. Much happier with weight for it, if it was gonna be a bench gun and hunting from blind I wouldn't have cared.

[Mesa1978]

20" Shilen DCM mounted on a squared and bedded MUR upper, lower BRO billet.

[dmsims21]

I went with a Vltor MUR too.
Best of both worlds and looks cool.
Either way, you want an upper that is machined well.

[LRRPF52]

For bull barrels, I like to use billet uppers/sets to balance out the rifle, although it isn't necessary.

I care more about squareness and fit with the lower for a solid-feeling rifle for accuracy, although there are plenty of guns with slop that will shoot very well.

I like as tight of a fit as I can get/make with the barrel extension and tunnel in the upper. The main reason I see where billet sets offer advantages are in features other than machining method, since there are so many options on the market.

The Mega and Seekins sets are excellent, as are Precision Firearms. I can't think of a billet set that is fit better than PF's, and that's before you install the pins.

The truth is that we are so spoiled with both routes, it isn't even funny nowadays.

[just_john]

Unless there is one of those "OOP!!!" moments, either works well. However, the pressures of the process of actually doing the forging results in a piece of metal that is far stronger than billet. Forging are accomplished by placing a piece of metal between a set of "forms" and then putting an instantaneous "squeeze" on it. In some cases, this is done several times in quick succession. With each "squeeze" moment, the actual molecules of metal are compacted and are forced to re-arrange so that they all still fit. The result of this process is a much more uniform grain structure that yields far more strength per cubic inch than billet.
Billet is simply the result of molten metal pushed or poured thru a form to result in a particular cross-sectional shape of some defined length. This may contain microscopic voids and impurities in random places and of random sizes. Part of the "creation" process is testing to classify strength, yield and elasticity parameters of the piece so that it recieves some classification.
Personally, I build all of mine with forgings. While I have most of the AR's that I have built, some were passed to my Grandkids and some friends and, if there ever is an "OOPS!" moment, I don't want any bad news to follow it. Got to keep the excitement focused on the target.
PS - did you ever hear of a billet barrel ( except for cheap .22's )?

[Adam Lilja]

As a machinist I like a precision beast and only use billet sets.

[gpsman007]

The military have successfully used forged receivers for decades. More than strong enough, lightweight and dependable,

[wraith1516]

I bought a cheap Anderson upper and lower a while back they are accurate enough to hit any thing I want out to around 500 meters (longest range I have ) only payed $45 for the lower and $40 for the upper (not counting ffl fee $30 for lgs to order it for me) joebob outfitters has them ok sale now

[wraith1516]

Finally got the chance to shoot the Anderson lower that I put together today it worked great for $45 it is good for a build on the cheap.
used it on my Rguns 223 and my grendel upper no problems

[Klem]

Both forged and billet meet the minimum strength needed in the AR. Arguably more important are the tolerances of the manufacturer's equipment. How tight are the holes drilled. How square is the upper receiver to the barrel axis.

High-end manufacturers like Mega include a nylon tipped screw in the lower designed to eliminate any slop between the upper and lower. Ironically their manufacturing precision is such that you don't need it. It's the cheap-and-cheerful manufacturers that should be the one's including this feature.

[LRRPF52]

I got 2 forged lowers from Precision Firearms recently. They are some of the best forged lowers I've ever seen. They initially look like your plane Jane A2-type forged lower, but closer inspection will show that the magazine well is generously flared with a 50* angle. Additionally, they have the threaded tension screw channel described above, but it isn't needed on any of the uppers I have tried them on, which include a Seekins billet and keyhole forge code M4 upper. The lugs of both fit tightly and securely in the PF lower, and Mark machined them specifically for a nice tight fit.