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schwann_oltorain
October 13, 2012, 11:38 AM
Hai guys so could someone tell me the differences between gas piston and direct impigment system in an AR. I was looking at the colt Le 9620 for target shooting but since it was gas piston I was curious if it will be good out to (how many yards?) without losing accuracy.

Or should I just go and step up my game with an LMT, DD, Sabre, Noveske. Getting the best M4 for my money in target shooting. Thx.

chronic
October 13, 2012, 02:54 PM
That there is a good question, wish someone would answer it.

pturner67
October 13, 2012, 03:20 PM
http://www.youtube.com/watch?v=6auXTiqNtEo


http://www.youtube.com/watch?v=rcyGsaHmARI

madcratebuilder
October 14, 2012, 06:30 AM
For a super accurate M4 look to Noveske. Service rifle like performance.

Adding a piston to the AR degrades accuracy.

BPowderkeg
October 14, 2012, 08:31 AM
i do not know about the "colt Le 9620", but i have been shooting the LWRC and LWRCI piston guns for about 10 years, the accuracy equals any DI gun and in some instances surpasses DI guns.

i own and shoot both, piston and DI, my LWRCI M6 piston gun will place bullets in the same human sized "kill zone" targets as my Colt HBAR DI at ranges of 50 to 500 yds. with similar scope set ups.

Adding a piston to the AR degrades accuracy.
this is pure nonsense.., at least in my experience !! :D i believe this has been disproven many times by average shooters across this great country, it all depends on the QUALITY of each gun and the shooters ability.

schwann_oltorain, i believe you will NOT go wrong in buying a Colt LE 9620

madcratebuilder
October 16, 2012, 08:11 AM
Quote:
Adding a piston to the AR degrades accuracy.

this is pure nonsense.., at least in my experience !! i believe this has been disproven many times by average shooters across this great country, it all depends on the QUALITY of each gun and the shooters ability.

Adding moving parts to the barrel well degrade accuracy, period.

Take two identical AR's with tested identical accuracy. Add a piston to one of them and you well see a decrease in accuracy. It well not be a lot but it well be measurable. I'm not saying piston guns are inaccurate, just that the same gun in DI well be more accurate. Most shooters would never see the difference because of shooter limitation.

Look at all the work service rifle guys have gone to over the years with Garands and M14 to eliminate gas cylinder induced barrel harmonics. This is why the DI AR15 dominates service rifle competition these days, less barrel harmonics.

BPowderkeg
October 16, 2012, 10:01 AM
Take two identical AR's with tested identical accuracy. Add a piston to one of them and you well see a decrease in accuracy. are you speaking of bench rest accuracy or combat accuracy ??

there is the problem, adding a piston to a gun that is NOT designed for a piston will certainly show a decrease in accuracy, velocity and pressures, i own dedicated piston carbines (LWRCI) and dedicated DI carbines (COLT) they both shoot equally accurately with exact same ammo...., by "accurately", i am NOT speaking of one hole groups or even 1/4" groups, i am speaking of man killing groups out to 500 yds. and for me that is accurate enough.

please, let's not argue over accuracy of DI over Piston, the difference if any is so minute the average weekend shooter will not see the difference....., IF ANY ! :D

raimius
October 16, 2012, 10:20 PM
If you are looking to be shooting at several hundred yards, I recommend going with a longer barrel for that little extra velocity. For the "average" weekend shooter at 100 or 200 yards, a 16in barrel will be more than adequate. For that kind of range, the DI or piston question doesn't matter much either. Both will be at least as accurate as the average shooter.

madcratebuilder
October 17, 2012, 08:11 AM
please, let's not argue over accuracy of DI over Piston, the difference if any is so minute the average weekend shooter will not see the difference....., IF ANY !

Agreed!;) Most would not notice any difference in a non precision build.

insomni
October 17, 2012, 09:47 PM
I prefer to own a piston because it takes all of 20 minutes to scrub down after I go to the range, as opposed to an hour or so for an M4. There's hardly any carbon in the receiver. next to none in the bolt carrier, zero on the trigger assembly. The bulk of my cleaning time is spent on the chamber and the gas plug.

I can rip out a thumbnail sized shotgroup from the prone at 25m with my piston gun just like I can with an issue M4

Both are service grade. I imagine the GI system would really only be noticible in an ACTUAL match grade rifle.

chris in va
October 17, 2012, 10:52 PM
Wait, I thought the LE 9620 was direct impingement.

en-frame
October 18, 2012, 12:03 AM
You're right, Chris in va. The Colt LE6920 is DI. The Colt 6940P is their piston carbine. Though I happen to have a "6920P", I don't think Colt sells them like that. ;)

Tim R
October 18, 2012, 12:43 AM
Might be good to define "target shooting".

My target shooting takes me out to 600 yards. Here barrel twist will make a difference in the ability to use heavy bullets.

There are a couple of off the shelf rifles which work well out at distance. The RRA NM is one which has the right set up for long range.

I have not seen a piston AR on the line at a match.