What is the point? We have already seen the downside: carrier tilt to start with.
I know that the AK is the most reliable assault rifle in exsistance. Are we just trying to mimic the piston in hopes that the AR will be just as reliable?
If this has already been discussed then I apologize, I’m new to this forum and just picked up my first AR in quite a while (DDM4)
Thnx
it has been discussed about a million times…
one thing, however- the AK is no more reliable than a well-maintained quality AR. less so, in fact.
Does the HK416 have a carrier tilt issue? Most seem to argue that the 416 is the M4/M16 taken to its highest level of perfection and it is a piston system. Personally, I think the 416 still needs a few more changes to achieve that status.
pistons with their recoil springs at the piston (im sure there’s a specific name for it) don’t have carrier tilt, because they don’t have receiver extensions or carriers that extend beyond the receiver… AKs, M1As, masada, etc- tilt isn’t an issue.
If my admittedly limited knowledge is not in total error, the design of our direct impingment system was intended to reduce weight from that of piston-operated guns. And that it does admirably. The trade-off is in getting crud more deeply into the bolt-carrier and allied parts of the mechanism, requiring greater attention to maintenance by the operator.
To me, direct impingment is what makes an AR an AR. Piston operated guns have their own merits. Neither is better nor worse, just different. IT’S ALL GUD!
I don’t think that’s why they don’t have carrier tilt, on the AK and M1A’s (and FAL’s and AK derivatives like the SIG 55x, Valmet, Galil, etc.) have carriers that ride on RAILS. This prevents tilting. In the AR, the carrier is just “free floating” inside the upper.
Not to mention that none of those have the same type of bolt lugs as on an AR which is yet another negative and wear point in these piston retrofit kits.
If someone wanted to make a REAL AR piston, they would need to use an internally railed upper and a slotted carrier. As for the bolt lug shearing, I don’t know what could be off the top of my head but I’m sure someone smarter than me could figure something out.
I always wondered why the new “Armalite” didn’t make a Masada-like upper for an AR lower that used the AR-180 piston system. They own the design, they have the tooling, and polymers are cheap and easy to work with. When you look at the original Masada/ACR design it recycled a lot of AR parts, just like the AR-18/180.
I don;t think it is a solution looking for a problem as much as it is a solution looking for a market. And it found one. I am sure that you can, given time, make a reliable piston-driven AR. Maybe they already have, I’m no expert on them.
But I trust my DI Colts without reservation. And I can clean them with my eyes closed, and know exactly where I need just two drops of oil to make them run like a champ.
Out of curiosity, what do you base this on?
The first time I saw the Magpul Masada was on that famous episode of Future Weapons. If my memory is correct, didn’t Mack say (and show a diagram of it too) that the only parts Magpul kept from the AR design was the barrel, trigger group, front sight post, and bolt (at least I think they said the bolt)?
I may be wrong here, but that’s what I remember from that episode anyways.
Yes, I have seen it first hand in a military unit running the 10.5" HK 416. It did not happen in every rifle but it did happen. I am not sure why it some rifles did not have this problem. Maybe round count played a role. Maybe too much play in upper/lower. I am not sure of something like an Accuwedge would fix the problem.
I don;t think it is a solution looking for a problem as much as it is a solution looking for a market. And it found one. I am sure that you can, given time, make a reliable piston-driven AR. Maybe they already have, I’m no expert on them.
+1
As someone who has owned a gas-piston AR, I wouldn’t consider myself an “expert” on the subject, but I do feel I know a little about the issue. A few years ago I jumped on the bandwagon and bought POF upper; and it worked as advertised, reliable and clean. My big problem is that it weighed more than my other AR-15’s, especially with my Surefire M900, and the recoil seemed heavier. Also the proprietary parts worried me; if anything ever broke, I would have only a single-source supply. Last year, I sold it, and took the proceeds and bought a top-of-the-line Troy upper to add to my lower, and have been very happy since.
Like others have said, I know the ins and outs of the AR well, and one can get spare parts for a conventional AR anywhere. Unless some manufacturer can win a significant military contract, parts will never be as ubiquitous as conventional AR parts, hence they will cost more and be more difficult to acquire.
While many gas-piston AR’s are excellent, they don’t represent such a quantum leap forward in technology that it would require every fighting man to get them. Especially since, in the end, it launches the same 5.56 rounds a conventional AR does.
Now, when someone develops a phaser, I will be first in line to buy one!
I think they said “…just the front sight post.”, but they were halfway kidding. The barrel is the same with a different extension in order for for it to use the QD system. The trigger group and pins are the same since no one has really ever complained about them being substandard.
[Edit:] In the pursuit of accuracy, I found this quote online and can see how it may have been attributed to Magpul “…'The best way to improve the AR-15 is to unscrew the front sight, and put a new gun under it.” - Kevin McClung, aka Mad Dog. (which is just what MagPul did when they developed the Masada)’ …" I think that quote made it on to one of the promotional posters put put by Magpul in reference to the Masada.
Magpul advertising poster (PDF)
Submitted for discussion sake: “M4 “Loses” Dust-test”
http://m4carbine.net/showthread.php?t=9789
"Newer carbines outperform M4 in dust test
Army Times
By Matthew Cox - Staff writer
Posted : Monday Dec 17, 2007 6:42:21 EST
The M4 carbine, the weapon soldiers depend on in combat, finished last in a recent “extreme dust test” to demonstrate the M4’s reliability compared with three newer carbines.
Weapons officials at the Army Test and Evaluation Center at Aberdeen Proving Ground, Md., exposed Colt Defense LLC’s M4, along with the Heckler & Koch XM8, FNH USA’s Special Operations Forces Combat Assault Rifle and the H&K 416 to sandstorm conditions from late September to late November, firing 6,000 rounds through each test weapon.
When the test was completed, ATEC officials found that the M4 performed “significantly worse” than the other three weapons, sources told Army Times.
Officials tested 10 each of the four carbine models, firing a total of 60,000 rounds per model. Here’s how they ranked, according to the total number of times each model stopped firing:
• XM8: 127 stoppages.
• MK16 SCAR Light: 226 stoppages.
• 416: 233 stoppages.
• M4: 882 stoppages."
In my opinion, that dust test doesn’t paint a fair picture of the competition. In a competition of extreme attrition I will concede that the AR15 may not be the best choice.
If we were to make the contest a bit more realistic, my first question is who fires 60,000 rounds in a firefight? Our troops carry approximately seven magazines on them at one time? Maybe more, maybe less but lets say seven thirty round magazines, that means they can only fire up to approximately 210 rounds. I can understand wanting to see how long the AR15 can stand up to rapid firing in harsh conditions but 60,000 rounds is not just a pretty ridiculous number but an unrealistic number. Secondly, lets talk about the abuse it can take. For instance, the FN SCAR has had a couple of reviews come out from soldiers who got to play with it. It sounds like the buttstock is pretty fragile and prone to breakage. While I am sure it happens, I personally have never seen or heard of an AR15 buttstock break. Consider the small number of SCAR stories versus the extremely large number of AR15 stories and that is a little scary. The 416 has also had its share of problems despite, there is a very interesting article floating around about a PD in Arizona who couldn’t get any of there 416s to work properly, HK couldn’t find any problem with them, and instead offered to completely replace the rifles.
The point of the story is that there no perfect system. Actually in my opinion, when it comes to the AR15 the gas system is the least thing I worry about.
I shoot my LWRC M6A1 more than my 6920 at this point, but I am not about to give up my 6920 either
The dust test involved 10 examples of each competitor that each fired 6000 rounds. hence the 60,000 round figure.
You can’t lump all piston guns together either. The HK416 has served several years with Tier 1 units that may fire mores rounds in a month of practice than other units do in a year. It is certainly not 100% perfect, while other pistons seem to be lesser degrees of perfect–often with dramatic differences between individual ones and even individual units for the same model.
And I have a piston AR, but am considering replacing one of my DI ARs–a Noveske N4 Basic–with yet another DI AR–a Colt 6940.
I think most piston owners are in a similar situation. I don’t think it needs to be all or nothing either way.
Though, truth be told, my AR15 piston collection probably wont expand beyond the one LWRC M6A1. Unless there is some utterly SICK deal on a 416 upper somehwere
For piston kicks I’ll get more XCR stuff, add an ACR, a FAL and TAVOR in 2010.
Now there ya go!