Steel vs Aluminum GBBR internals
 

Hey guys,

Just wondering if anyone has any experience in dealing with G&P GBBR M4s with steel internals and ones with aluminum alloy internals, i.e. WOC vs. WOC-X.

I'm building a G&P GBBR M4 and I'm not sure if it's worth the extra money to buy steel internals for it.

I'm planning on running propane through it or using the GHK Co2 mags, plus an Inokatsu Superbolt and upgraded recoil system.

I'm assuming I'll need to go steel with those specs, but could someone please let me know if the Aluminum alloy parts will work just as well?

Also, I tend to baby my rifles as I'm a filmmaker/chairsofter.

Thanks all

are you building it from scratch? or buying a base gun?

With the GBBRs...it's worth giving serious consideration to having steel components run/bear/actuate against steel components (or alum vs. alum...like against like).

Steel will quickly wear out pot metal or alum parts. For example....the sear catches of a pot metal/alum hammer will be easily worn by a steel sear.

That said...also consider what parts would fail...and it may be preferable to have one specific part fail vs. another (i.e. I'd rather bust a nozzle vs. bolt carrier....I'd rather the nozzle tip went vs. the nozzle body....etc...)

Once the accelerated wear aspect is dealt with...there's also the durability aspect. GBBRs take quite a pounding internally. There's big chunks of metal cycling very quickly inside and this generates a lot of force.

It's "simpler" to say...go steel for everything...but that may not be the be all and end all depending on what you want to achieve.

Building it from scratch like you did. I have the G&P Vltor Aluminum body and I was going to buy the internal kit like you, but since it's Aluminum I wasn't sure if it'd be able to take the superbolt and upgraded recoil system with propane or Co2

And also, let the parts break-in, if you're building from scratch....

It took almost 4 months for my body + bolt + other internals to break-in, (ie cycle smooooothly.... :P)

(just let it sit, fully assembled ofr a while...lol)

EDIT: this I what I bought, G&P reinforced assemble set And AFAIK they are all steel, not aluminium....

Also, I would recommend getting a G&P outer barrel + G&P hopup rubber, (5ku and ratech didnt work well....5ku barrel wasnt straight... it was curving up.....:S)


EDIT of EDIT: o wait, they ARE aluminium.... lol.... except for the main parts, like the Hammer, Full auto sear, mag catch, selector are steel....and some other pieces.... cant remember...lol

And they are solid, dont worry :P

That's what I was figuring Tys, but I wasnt sure. I guess I'll look too at what kind aftermarket parts RA-Tech is putting out there as they would design parts that would compliment what's already in a GBBR, i.e. if they sell a steel bolt carrier group for G&P WOC rifles then steel parts would probably be needed with the Inokatsu Superbolt which has similar, if not like, build materials.

I'm looking for strong recoil, fairly realistic cycling speed, and ability to handle higher pressure gases like propane or Co2. Going with what you said, I would imagine that a steel hammer and barrings, steel sear, steel bolt stop and steel hammer lock would be in order to handle the steel bolt.

Thanks so much for the input.

Are you sure? That's what I was going to buy, but it states that they're made of aluminum alloy. Are you sure they're steel? Or is it just some of the parts that are steel?

some of them... (look at the edit i made of my post...lol)

BTW: you might want a heavy bolt, but light buffer.... at least to plink during winter....

Since RAtech heavy buffer + heavy bolt as causing slughish cycling, and intense cooldown....

i don't think it matters too much, with the exception of using like materials together. as for durability, there wont be much difference when it comes to parts that will be taking a lot of impact force.
Aluminum parts are light, therefor they have less inertia, but at the same time they are comparably softer.
Steel (mild steel) parts are much heavier, and so have quite a bit more inertia. this wouldn't be a problem if the steel used was a quality steel that has been case hardened(which in our case, it never is.).
case in point: my RA-TECH steel (mild steel.. sad.. really sad) carrier has the whole from face of the carrier deformed for impacting my Prime steel barrel extension (better steel used). it's gotten so bad, it scrapes the inside of the upper after only 2-3 hundred rounds.
same thing happened to my stock WA carrier (pot metal), so i really cant see any reason to pick one material over another other then cost.
stay away from hammers that have steel bearing on the top where it contacts the carrier, as the bearing is made from hardened steel and will eat through both Aluminum and steel carriers, that is of course unless the carrier is made from a quality carbon steel that has been case hardened(unlikely).

recap -
Aluminum- light, soft, it doesn't flex, it bends or deforms with impact.

Steel (mild steel)- heavy, harder than aluminum, still soft. it doesn't flex, it bends or deforms with impact.

quality steel (good carbon content, case hardened)- same weight as mild steel if not a bit lighter, super hard, flexes, absorbs impact well, will out last the rest of the GBBR. too bad no one cares to make internals with this kind of steel. i guess it would be counter productive to make parts that last.