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Mid-Length Gas System?

Posted: Wed Mar 13, 2013 4:48 pm
by snatchel
Hey folks. I bought a Troy Defense Carbine today: http://www.troydefense.com/firearmsacce ... 6-carbine/

Anyway. I prefer the look to a longer handguards and mid length gas systems, but I'm not sure if there is a real advantage to a middy over a carbine or what-have-you. Thoughts?

I'd post pics, but right now it's a basic carbine with a lot of magazines and not much else. I should have all the lego parts put together by the weekend so I can post pictures.

Re: Mid-Length Gas System?

Posted: Wed Mar 13, 2013 5:17 pm
by Sputz
Most people perceive them to have less recoil. I can't tell a difference. I like the longer handgaurds though.

Sputz

Re: Mid-Length Gas System?

Posted: Thu Mar 14, 2013 11:11 am
by gigag04
Less recoil = longer lasting BCG

Also, longer sight radius = increased iron sight accuracy.

Lastly, I believe the dwell timing also increases reliability.


Most of these things (minus sight radius) are virtually non-issues anyway with modern, quality carbines, but nice to have fore sure.

Re: Mid-Length Gas System?

Posted: Thu Mar 14, 2013 11:47 am
by psijac
I was reading that would get the dwell time right on a carbine length gas system you need to use a h2 buffer. This increases felt recoil. Of course I read this online so Bonjour!

Re: Mid-Length Gas System?

Posted: Thu Mar 14, 2013 4:01 pm
by snatchel
Thanks for the replies guys. I haven't shot it yet.... I could, but I'm going to wait till tomorrow for the scope mount to come in so I can sight both the irons & sope in the same outing.

I'll post a different thread on range report/etc.

Re: Mid-Length Gas System?

Posted: Thu Mar 14, 2013 7:54 pm
by ske1eter
AndyC wrote:Biggest advantages I can think of are a slightly longer sight-radius over the carbine and a less harsh gas-pressure spike on the BCG due to a longer gas-tube. I chose a middy as my first build for those reasons; I wanted some longevity in the rifle's parts but didn't want to go to a full-size rifle to get it.
What AndyC said. :tiphat:

Re: Mid-Length Gas System?

Posted: Sun Mar 31, 2013 9:19 pm
by OldCannon
Theoretically, the AR-15 was never designed for carbine (or shorter) configurations. In practice, it's turned out to be a pretty decent rifle for that purpose, although I've now seen some downright unholy things done with AR-15 impingement systems :mrgreen:

If you want super-nerdy, read this: http://www.ar15barrels.com/prod/operation.shtml" onclick="window.open(this.href);return false;

My short version: An 18" barrel with a rifle length gas system will yield the most awesome AR-15 ever. Second-best choice: 16" barrel with mid-length.

Re: Mid-Length Gas System?

Posted: Sun Mar 31, 2013 11:36 pm
by The Annoyed Man
18" barrel with a mid-length gas tube will yield slightly higher muzzle velocities at slightly lower pressures.

Re: Mid-Length Gas System?

Posted: Mon Apr 01, 2013 12:04 am
by gigag04
OldCannon wrote: My short version: An 18" barrel with a rifle length gas system will yield the most awesome AR-15 ever. Second-best choice: 16" barrel with mid-length.
Hard to make the assessment w/o having an intended use in mind no?

USSOCOM spec'd a 10.x" DI gun and also a piston gun and for their usage, the marines a 16" piston, and the army a 14.5" DI carbine length gun. 18" middy's are great for SPR builds, DMR type roles, or faster 3G courses. I find them too heavy and unwieldy for the majority of my applications and needs (rapid deployment, agility, and weight).

But I generally agree that a middy runs awesome. Carbine's are battle proven too.


I personally think a 20" + bbl on a rifle gas system with a 15" hand guard is a treat to shoot but without application in my life.

Re: Mid-Length Gas System?

Posted: Mon Apr 01, 2013 10:59 am
by williamkevin
GREAT thread here!

Re: Mid-Length Gas System?

Posted: Mon Apr 01, 2013 1:33 pm
by OldCannon
gigag04 wrote:
OldCannon wrote: My short version: An 18" barrel with a rifle length gas system will yield the most awesome AR-15 ever. Second-best choice: 16" barrel with mid-length.
Hard to make the assessment w/o having an intended use in mind no?
Fair enough. I was definitely making a general assessment of the AR-15 platform. Most civilians don't really need CQB-style designs (buy, hey, this isn't about _needs_, is it? :mrgreen: ).

Re: Mid-Length Gas System?

Posted: Mon Apr 01, 2013 1:50 pm
by snatchel
I ended up getting a mid-length. And yes... it does run awesome! I've been running garbage ammo through it too--Wolf & Tula-- and it still runs like a champ. Absolutely no teething issues, no FTF, FTE, or anything else. And it's smooth.

I will agree that it's a bit heavy, but I have had no issues carrying it around 8+ hours a day.

Re: Mid-Length Gas System?

Posted: Mon Apr 01, 2013 4:06 pm
by pcgizzmo
OldCannon wrote:
gigag04 wrote:
OldCannon wrote: My short version: An 18" barrel with a rifle length gas system will yield the most awesome AR-15 ever. Second-best choice: 16" barrel with mid-length.
Hard to make the assessment w/o having an intended use in mind no?
Fair enough. I was definitely making a general assessment of the AR-15 platform. Most civilians don't really need CQB-style designs (buy, hey, this isn't about _needs_, is it? :mrgreen: ).
IF you were going to think about using this for home protection wouldn't CQB be the best?

Re: Mid-Length Gas System?

Posted: Mon Apr 01, 2013 5:23 pm
by gigag04
I'm still not convinced HD is the BEST role for an AR in my home. I have sheetrock walls and loved ones around many corners so I prefer a slow, fat, hollow .45acp. Again...needs depending. Some of my ARs could be used for home defense if needed but my main one (and easiest to access) is setup for its most likely use at work which is a perimeter or robbery...likely a shot at or around 50 yards or more. Active shooter too, possible but less likely.

(Broken English...on phone. Sorry...)