My question(s) to you guys is this; How does one tell the defference between cast and forged lower receivers?  Pros and cons of both?  Which is better?  Lastly, the ever popular bbl lining.  Chrome, SS, chrome moly, is the difference in accuracy, durability or both? Thanks in advance for your insight!!!

JohnnyB

I have all three:

The Chrome lining is said to make accuracy not as good, but for practical shooting, not likely to be noticable.  Advantage, said to be slightly easier to clean, and the bore and chamber are corrosion resistant.  My Armalite has the chrome lining.  To me, I would just as soon have SS.

Stainless is also corrosion resistant, and I note that the very best target barrels are stainless.  I note that stainless is corrosion resistant both inside AND outside.  Some do not like a shiny finish on stainless barrels, and I agree.  But a simple bead blasted finish yields a matte gray which blends well in urban or woods surroundings.  My Oly Ultramatch is a tack driver.  This is a 1" bull barrel, free floated upper, with a Leupold Vari-X III 6.5-20x, and JP hammer/trigger.  Can't make a valid comparison to my other barrels.

Until very recently, I also had a 16" upper with Oly SS bbl, and a 20" Oly Service Match upper.  Both were excellent, and no difference in accuracy as compared to my Chrome Moly barrel, which are of similar contour.

Plain unlined Chrome Moly, well, most other firearms on the market seem to do just fine with 4140 Chrome Moly, without chrome lining.  And my  four CM barrels from J&T and DPMS shoot well, too.  I don't have any problems with them, and they clean up as easily as my SS barrel.

None are near a point where I can judge durability, and compare one to another.  From what I have read, this greatly depends on how the barrel was treated during its lifetime, heating up in full auto fire (which I does not apply with me), etc.

For a rifle (or any other firearm) to be used in coastal or sea water environment, stainless is the only way to go.  Not an opinion, fact.  For a general shooter, any of the three, SS, CM, or chrome lined are fine.

Cast lowers are just fine, you will have people try and tell you it makes a difference but it will not, some of those same people will on other post tell you how good and durable the plastic ones from calvery arms are, and they are correct. the most important thing is that you get it from a reputable manufacturer, the machine work is the important thing. cast and forged do have different failure properties but unless you are comparing race car pistons you are wasting your time worrying about it, kind of like worrying about whether or not your microwave door handle is cast or forged. This is not a stressed part of the gun and the only difference it will make is if you were selling it to someone who thought it mattered.
I have heard that the DPMS cast lowers are heat treated or something prior to machining to insure a quality product.
as far as telling the difference it would be best to call the manufacturer, different brands have different clues, but usually a forged will have the company name indented while cast will have it raised.

This is the techinical answer. Believe it if you want, but I have found that my most accurate barrels are unlined. Also, last year while I was still frequenting AR15.com, one poster brought up the fact that a chrome-lined barrel has never taken home the money at Camp Perry. Actually, I believe he used the term "any money".

Now, on the 'pro' side for chrome-lined---
The lining roughly doubles the strength of conventional steel. As a result, the life of the barrel is said to double as well. The effects of throat-errosion and normal wear are reduced.

I've found an easy way to tell whether a receiver is forged or cast. Look at the front of the magazine well's exterior. If there's a line about 1/4" wide running down the center, it's forged. The line is a result of the forging process. Also, companies like DPMS indicate casting and forging in their serial numbers. My forged receivers begin with "F" in their serial numbers. I'm told the cast ones begin with "C".

Which is better?...forged...but you will probably never notice a difference.

Hope this helped. It's mostly hearsay but I believe it to be true.

Forged recievers are cosmetically better, stronger, and increase the resale value of your gun.

Will you ever need the extra strength of a forged reciever? Maybe, but most likely not. But do you really want to go with a reciever that looks worse, is weaker, and decreases the resale value of your gun to save about $30.00.

Probably the easiest way to tell a forged from cast is the markings on the receiver. A cast receiver markings will be cast in and raised above the receiver surface. Only the serial number will be stamped. A forged receiver will have all markings/numbers stamped into the receiver. As far as which is better? A good casting will last as long as a good forging. Don't worry about it. As to barrels...Chrome for your plinker firing a Heinz 57 mix of cheap ammo where you clean annually. Non-chrome stainless steel or chrome molly (an alloy, not chrome lined), the jury is still out. I personally like chrome molly for accuracy...just preference.

 I can't complain about the accuracy of my Bushmaster 20" chrome line barrel.  I'm not going to be shooing in any competitions either.  I'm confident that it is accurate enough to smoke any coyote or ground hog at 300yds no prob and that is without a floating hand guard.  I wanted one of Bushmaster varminter uppers until I found out it wasn't a chrome line barrel now I'm thinking of building a similar upper starting with a fluted 24" chrome line heavy barrel.  I'm sure the chrome affects accuracy but unless I'm shooting in a competition I don't think it makes that much difference. [USA]

Check out this FAQ from Olympic Arms:

[url]http://www.olyarms.com/castorforged.html[/url]