Not sure if the 4150 barrels are really better than 4140 barrels. I have heard they are better, but is it noticeable if you are not going full auto.

almost everyone uses 4140 except:  Colt, Fn, Bushmaster and maybe CMMG.

as long as your not "simulating" full auto fire aka bumpfirinng mag after mag you'll never know the diff. IMO>

Quoted: almost everyone uses 4140 except:  Colt, Fn, and Sabre Defense.

Quoted: Quoted: Quoted: almost everyone uses 4140 except:  Colt, Fn, and Sabre Defense. And Bravo Company and...

Noveske.

Colt, LMT, Sabre Defense, CMMG, Bushmaster, and Noveske all use 4150 steel.  They all offer chromelined barrels as standard features.  If you take Bushmaster out of the list then they all offer 1x7 twist rates and MPI every barrel.  Bushmaster does offer 1x7 as an option and batch tests their barrels. IMHO having a chromelined barrel is more important than what type of barrel steel was used.  Rust inside of your barrel will wear it out faster than any amount of shooting you do.  

Most of the other companies use Wilson barrels.  They come standard non-chomelined with a 1x9 twist.  For an extra $45-50 you can get a chromelined version.  

But by the time you pay extra for the chromelined 4140 barrel you could have purchased a MPI barrel from any of the companies that uses 4150 steel except Colt.  

The companies that use 4150 steel also offer quality controls that the other companies don't.  According to some engineer/industrial types who have posted on here there is very little difference between the two types of steel.  I don't know I'm an end user, but there's a reason that Mil-Spec barrels all seem to be made out of 4150 steel, and that many companies continue to use it even though it is reported to be more expensive.  

ETA:  I forgot BCM and probably a few other manufacturers who use 4150 steel.

Quoted: Quoted: Quoted: Quoted: almost everyone uses 4140 except:  Colt, Fn, and Sabre Defense. And Bravo Company and... Noveske.

Global Tactical

Okay, so basically all the loser companies which make crap uses the 4140 steel.

Quoted: Okay, so basically all the loser companies which make crap uses the 4140 steel.

Probably, but there are some quality 4140 barrels too.

Quoted: Okay, so basically all the loser companies which make crap uses the 4140 steel.

yes 4150 > 4140
but 4140 != crap

I am also not sure I would say that there is an abundance of "crap" out there.  it just depends on your needs and requirements.

height=8

Quoted: Okay, so basically all the loser companies which make crap uses the 4140 steel.

no, just barrels that are required to be "mil-spec" (not that mil-spec means a damm thing anyway) and that is moot as not all 4150 steel is mil-spec. some reading for you
www.ar15.com/lite/topic.html?b=2&f=138&t=148891

you, the non-full auto person would notice more difference in the quality of the rifling, the crown and attributes OTHER than the steel. Heck, I am not even sure the full-auto person would notice the difference.

4150 or CMV will increase the temp to burst the barrel and decrease throat errosion.  If you wont push your barrel till it glows or shoot enough to wear it out you will not notice the difference.

I like my LMT 14.5 barrels
They happen to be made of 4150 so be it