Question regarding upper
Firearm & Gun Forum - FireArmsTalk.com > Long Guns > Auto & Semi-Auto Discussion > AR-15 Discussion > Question regarding upper

Reply
 
LinkBack Thread Tools Display Modes
Old 08-22-2012, 03:36 AM   #1
Feedback Score: 0 reviews
 
xdm11chad's Avatar
 
Join Date: Sep 2011
Posts: 150
Liked 2 Times on 2 Posts

Default Question regarding upper

There is 2 different upper types piston I think and gas? Please if that is right explain the difference for me, I'm about to drop $650.00 on a Adams Arms 16" piston upper

__________________
xdm11chad is offline  
 
Reply With Quote

Join FirearmsTalk.com Today - It's Free!

Are you a firearms enthusiast? Then we hope you will join the community. You will gain access to post, create threads, private message, upload images, join groups and more.

Firearms Talk is owned and operated by fellow firearms enthusiasts. We strive to offer a non-commercial community to learn and share information.

Join FirearmsTalk.com Today! - Click Here


Old 08-22-2012, 03:38 AM   #2
Feedback Score: 0 reviews
 
purehavoc's Avatar
 
Join Date: Oct 2011
Location: Not where I wanna be
Posts: 4,750
Liked 1133 Times on 737 Posts
Likes Given: 2021

Default

Piston and direct impingment. The piston setup is a little cleaner. The bads. Not as reliable and heavier.

__________________
purehavoc is offline  
 
Reply With Quote
Old 08-22-2012, 03:50 AM   #3
Feedback Score: 0 reviews
 
USEBOTHHANDS's Avatar
 
Join Date: Jan 2011
Location: Ferriday,LA
Posts: 1,332
Liked 650 Times on 368 Posts
Likes Given: 5125

Default

supposedly the piston drive is ALOT cleaner, runs WAY COOLER, and runs MORE reliably. the weight difference, from what i've read, is between 0.0 and 5.0 oz (about 1/4lb to 1/3lb). the AK is a piston drive.

__________________

"they may get me in a rush, but not before i turn your head into a canoe....." -Kurt Russell (Wyatt Earp) in Tombstone

"if it was up to me, i'd like to see, this country run,
the way it used to be, the way it oughta be, just like it's done, OUT HERE.........WAY OUT HERE." -Josh Thompson, country music singer http://www.youtube.com/watch?v=D0sYnro_3Rc
http://www.youtube.com/watch?v=P3R00rlA0S0&NR=1

PEOPLE TEND TO ACT LIKE SHEEP, BOY I LOVE MUTTON! -Me


Last edited by USEBOTHHANDS; 08-22-2012 at 03:56 AM. Reason: weight
USEBOTHHANDS is offline  
 
Reply With Quote
Old 08-22-2012, 03:54 AM   #4
Feedback Score: 0 reviews
 
AgentTikki's Avatar
 
Join Date: Oct 2010
Location: City of Lost Angels, Kommifornia
Posts: 3,445
Liked 335 Times on 264 Posts
Likes Given: 51

Default

http://www.firearmstalk.com/forums/f20/ar15-primer-beginners-guide-59600/

*Gas Systems.*

There are 2 major types of gas systems that the AR runs on. The first being DI (direct impingement) and the second being piston. DI is the original design. Piston is a relatively new development. There have been forays into piston designs in the past, but it’s only been recently that piston driven ARs have been become popular. The best thing I can do you is show you the pros and cons a piston system offers, it’s your personal choice to decide if it fits your needs. Please understand that since there is no set standard for a piston system, every piston system is a proprietary design that will require different and non interchangeable parts.*

Pros:
*A cleaner running system. (less fouling of the BCG and chamber, more fouling by the gas block or exhaust)
*Should be more reliable in adverse shooting environments.
*Should be easier to clean, (provided you don’t need to remove the hand guards)

Cons:
*Costs more than a comparable DI setup
*Weighs more than a comparable DI setup
*Harsher recoil impulse (I concede that this is subjective and debatable)
*Inherently less accurate,(minor)
*Slower follow up shots (minor)
*Proprietary parts make it harder, costlier, and longer to replace broken parts.

Personally, I would only recommend a piston setup if you where looking for a non precision type carbine and need the extra reliability due to your expected shooting environment.

DI gas systems come in 4 flavors: Rifle, mid-length (middy), carbine, and pistol. The most common types are carbines, with 7” handguards. The next most common types are rifles with 12” of rail. Relatively new developments are midlengths with 9” handguards. Pistols are uncommon and I won’t be going too much into them. Only consider rifle length gas systems for 18+ inch barrels. Both carbine and midlength gas systems can be used for 14” to 16” length barrels. For these lengths, I usually recommend midlengths as their advantages outweigh their disadvantages:
__________________
Assumption is the mother of all ****ups.
Know what you know, Know what you don't know. -Paul Pedzolt
"Jack of all trades, master of none, though oftentimes better than master of one" -Mynshul
AgentTikki is offline  
 
Reply With Quote
Old 08-22-2012, 04:12 AM   #5
Moderator
FTF_MODERATOR.png
Feedback Score: 0 reviews
 
JonM's Avatar
 
Join Date: Nov 2009
Location: Rochester WI,Rochester WI
Posts: 17,748
Liked 5801 Times on 3029 Posts
Likes Given: 397

Default

One thing i want to make note of. Gas pistons do NOT run cooler than di guns. They are the same. The laws of thermodynamics arent suspended just because you slap a piston on a gun. The heat goes somewhere. Its just whether you want to heat up the gas tube or the piston block.

Since it takes over 50 magazines at full auto non stop to blow up a gas tube or a piston its a non factor.

My experience with gas piston is the bolt runs cleaner but you cant run it dry anymore than you can run an m1a or m1 garand dry. You have to use lube. Gun oil such as rem oil or clp are extremely poor lubes regardless of design. My choice is 30weight motor oil. With a di gun generous usage of motor oil prevents junk being caked on and a simple wipe with a cloth is all thats needed to clean the innards.

__________________

"Gun control: The theory that a woman found dead in an alley, raped and strangled with her panty hose, is somehow morally superior to a woman explaining to police how her attacker got that fatal bullet wound." — L. Neil Smith

The problem with being stupid is you cannot simply decide to stop doing dumb things...

JonM is offline  
 
Reply With Quote
Old 08-22-2012, 04:53 AM   #6
Feedback Score: 0 reviews
 
USEBOTHHANDS's Avatar
 
Join Date: Jan 2011
Location: Ferriday,LA
Posts: 1,332
Liked 650 Times on 368 Posts
Likes Given: 5125

Default

Quote:
Originally Posted by JonM View Post
One thing i want to make note of. Gas pistons do NOT run cooler than di guns. They are the same. The laws of thermodynamics arent suspended just because you slap a piston on a gun. The heat goes somewhere. Its just whether you want to heat up the gas tube or the piston block.
your assessment of heat is correct. i apologize for the generalization and crawfish. the BCG runs ALOT cooler.
__________________

"they may get me in a rush, but not before i turn your head into a canoe....." -Kurt Russell (Wyatt Earp) in Tombstone

"if it was up to me, i'd like to see, this country run,
the way it used to be, the way it oughta be, just like it's done, OUT HERE.........WAY OUT HERE." -Josh Thompson, country music singer http://www.youtube.com/watch?v=D0sYnro_3Rc
http://www.youtube.com/watch?v=P3R00rlA0S0&NR=1

PEOPLE TEND TO ACT LIKE SHEEP, BOY I LOVE MUTTON! -Me

USEBOTHHANDS is offline  
 
Reply With Quote
Old 08-22-2012, 06:39 AM   #7
Feedback Score: 0 reviews
 
Quentin's Avatar
 
Join Date: Apr 2010
Location: Idaho
Posts: 6,593
Liked 1027 Times on 723 Posts
Likes Given: 1028

Default

Quote:
Originally Posted by USEBOTHHANDS View Post
... the BCG runs ALOT cooler.
Which doesn't matter a lot. The BCG can stand a little hot gas, it's not like it is gonna melt!

The main area where the piston can shine is in SBRs or suppressed ARs. For 14.5" and longer you just can't beat good ol' DI.

I would put that $650 into a better upper.
__________________

______
The biggest issue with assembling an AR isn't so much getting the parts together right - it's getting the right parts together. You'll remember the quality of a gun long after you forget how much you paid for it.
________________________________________
US Army 1966-69, VFW Life Member, Retired Geek

Quentin is offline  
 
Reply With Quote
Old 08-22-2012, 12:08 PM   #8
Feedback Score: 0 reviews
 
xdm11chad's Avatar
 
Join Date: Sep 2011
Posts: 150
Liked 2 Times on 2 Posts

Default

Thank you guys! The tables are now turned. My main use is shooting with all my buddies and will b target and small animals

__________________
xdm11chad is offline  
USEBOTHHANDS Likes This 
Reply With Quote
Old 08-31-2012, 01:11 PM   #9
Feedback Score: 0 reviews
 
fsted2a's Avatar
 
Join Date: Apr 2008
Posts: 1,120
Liked 225 Times on 177 Posts
Likes Given: 321

Default

Quote:
Originally Posted by Quentin View Post
Which doesn't matter a lot. The BCG can stand a little hot gas, it's not like it is gonna melt!

The main area where the piston can shine is in SBRs or suppressed ARs. For 14.5" and longer you just can't beat good ol' DI.

I would put that $650 into a better upper.
Yeah, the longer the barrel, the less advantage the piston has. Quentin and I each have a piston gun, and although they run nice, unless the prices come down significantly, I can't see building another with a piston. Better to invest the money in higher quality parts. "Nuff said.
__________________

"Democracy is two wolves and one sheep voting on what to have for dinner.
Liberty is the well-armed lamb contesting the vote." - Benjamin Franklin

fsted2a is offline  
purehavoc Likes This 
Reply With Quote
Reply

Thread Tools
Display Modes


Similar Threads
Thread Thread Starter Firearms Forum Replies Last Post
Simple Upper Question Shihan AR-15 Discussion 3 07-27-2011 05:03 AM
Upper Question easterner123 AR-15 Discussion 12 05-23-2011 01:29 AM
Upper Question? WoodysKJ AR-15 Discussion 6 03-26-2011 10:07 PM
AR Upper Build Question - DD Barrel Nut Hard To Thread On To Upper Cnynrat AR-15 Discussion 3 05-27-2009 03:52 AM
Upper Question Silvertip 44 AR-15 Discussion 1 11-15-2008 03:57 AM