Mega billet upper/lower v. ?

[SouthPark]

I am thinking about what receivers I might use in a build of a middy and I know some people think the Megas are pretty good. I know nothing about the difference between billet and forging, and I know Mega makes both and the billet looks pretty nice. I know LaRue makes a billet lower. Price is not a consideration. If you can educate me, please do so.

[cop1211]

I recently had Ranier Arms build an upper for me with the Mega mono billet rail/receiver. I love it. Very nice quality, looks good, and feels great in the hand.

[cymax]

hello i can't comment about the mega it self but i can educate u between the difference between a forging and a billet.

now first

a billet is a a rectangular peace of material that is then machined to what ever u want it to be. generally using a cnc mill or lathe

a forging is when the material in it's raw form is heated to a certain temperature and then placed under a mechanical hammer or a press with a die. the die contain the shape that u desire

now

7075 is the type of aluminum. t6 is the heat treatment used to give the material, in this case the 7075 certain material properties.

so how does this work of ar15 up and lower.

in the case of a forging the 7075 aluminum is first forged to the shape of the lower or upper. the aluminum is done by heating the aluminum to a certain temp. in order to make it malleable. once formed the forging is then heat treated to T6 specification. and u have a 0% are forging. further machining is then done to get a complete lower or upper.

now in the case of a billet. the material comes already heat treated.
it's the same material the same heat treatment,T6 except it comes in a rectangular shape and the upper or lower receiver is machined from it.

so from an engineering stand point, both billet and forging have the same material mechanical performance, the billet will allow more flexibility in manufacturing and customization and will generally cost more due to the material tooling and all the is necessary to produce it .

forging are great for mass production and less expensive but do not allow for the same flexibility ei customization. dies are extremely expensive to produce.

hope this helps

btw my background is mechanical engineering specializing in design and manufacturing if u would like more detail as to were the information is retrieved from i will site the books.

[socalav]

Forged lowers are also stronger

[payj]

My mega billet lower and mono upper are flawless. The quality is top notch......I think the only real thing that billet has going for it is looks imo. The strength/weaknesses in actual material and processes of making each type lower I don't think could every really be tested to its limits with the gun lower really. If it were a mechanical part of the gun then maybe, but it just holds the guts in. Maybe I'm wrong, but that's how I look at it.

[cymax]

Forged lowers are also stronger

sorry to disappoint but that is wrong 7075 is aluminum type chemical formulation. T6 is heat treatment for the aluminum.

now if both are from same material and heat treated to same specs then same strength

forgings are heat treated after being formed not before. so work hardening is not and issue.

work hardening is when the material is compressed and the crystal structure are compacted.

since heat treatment is done after the crystal structure reform.

[SteveL]

I've been curious about the issue of forging vs billet vs casting for a while and have been looking around the net for information on the topic. I came across this write-up (http://www.robertpowersmotorsports.com/BilletvsForged.html) explaining the differences and it sounds good to me (as an uneducated reader). I would be curious to see what someone with an engineering background like cymax thinks about it. This particular write-up is dealing with forged/billet/cast engine parts, but I would think the information would carry over to the firearms world as well.

[cymax]

I've been curious about the issue of forging vs billet vs casting for a while and have been looking around the net for information on the topic. I came across this write-up (http://www.robertpowersmotorsports.com/BilletvsForged.html) explaining the differences and it sounds good to me (as an uneducated reader). I would be curious to see what someone with an engineering background like cymax thinks about it. This particular write-up is dealing with forged/billet/cast engine parts, but I would think the information would carry over to the firearms world as well.

it's a real good write up but scratches the surface of the entire metal manufacturing world.

[SouthPark]

I always like to hear from an M.E. when we are talking materials. Thanks for your insight, and as you can see, this is a subject that might be worthy of a sticky in the tech discussion because most of us have no metalurgy background.

I can see now why billet costs more, since it must be machined similarly to a 1911. Functionally, it appears that there is no difference.

OK, now I am still looking for comments about Mega so I hope some more of you will chime in. Many thanks!

[lfromsalem]

You can not go wrong with Mega. I have done 4 builds using there stuff, all have gone together well.

If you would like to see the end result of my last build, send me a pm.

[Toonces]

sorry to disappoint but that is wrong 7075 is aluminum type chemical formulation. T6 is heat treatment for the aluminum.

now if both are from same material and heat treated to same specs then same strength...

Actually, socalav is right. Forgings are stronger due to the grain structure "flowing" with the contour of the part. The difference is not huge, but it is real. I would guess the largest difference between billet and forged is the area where the receiver extension screws into the lower.

With quality raw material, either has more than adequate strength for a lower.