powrsurg

I have the Colt MT6400R


It has the monolithic upper. ANyone know if its possible to convert this to Piston?

JeepApex

Should be able to drop in an Adams Arms or Osprey piston conversion kit. You'll have to change out your front sight/gas block. Not exactly sure why you'd want to ruin a perfectly good DI kit though.

ReconJeep

You are going to lose in accuracy and reliability. Even though your rifle will be cleaner, the aftermarket piston systems cause the bolt to tilt. This makes both the bolt and the upper receive wear unevenly. In the long run you'll have a loose bolt and a upper that will need replacing. If you do get the piston inside the monolithic upper, cleaning it will be more of a hassle than cleaning the original DI setup.


"Ex Umbris Venimus"

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sa29560

I believe the adams arms kit comes with a spring that goes on the back of the bolt after the gas rings are removed. This causes the bolt to push the carrier back into the receiver extension, thus eliminating carrier tilt. Of course, everything sounds good, I don't have one to say for sure.

My di works just fine, for three hundred bucks I'd just buy one of those fail zero bcg's

JeepApex

He's also going to lose speed. Any time I've seen piston guns shooting beside DI guns, DI guys ALWAYS run their kit faster. Working some of the speed drills with Magpul, even the SCAR was inherently slower than all the other DI rigs. There was a Ruger 556, Scar and one other who had a drop in kit. They were able to run it fast, but DI kits always edged them out.

powrsurg

My journey with the .223 /5.56 has really just begun. I have read that one of the things that makes the AK better is that it's piston operated. I'm surprised to hear some of the comments written here. Again I'm far from an expert with the AR platform but I would have thought I would increase reliability and accuracy. Speeds not much a concern since I'll never have either at full auto. You all have raised really interesting points.

Why would these conversions exist if you lose so much.

sa29560

I most definitely am intrigued by the adams arms kit. The speed is not an issue for me either.

Ar's are not really anything like ak's. Though I think they are both great engineering concepts from different sides of the globe. But the long stroke piston drive on the ak is, in my opinion, much of the reason it shoots anything, anytime, pretty much no matter what. Rusty steel cases, ammo buried for decades, it doesn't matter. Such a simple system with remarkable reliability.

Ak's are great for just popping off a few or even close range. But past 100m, definitely not the top shot. Just my opinion, they do have many positives.

Even then, many have built 7.62x39 ar 15s to have the accuracy and reliability. But in some research, magazines, and ftf / fte are all issues. Little bit of refining had to be done to the carrier, firing pin, mag well, or any variety of surfaces.

For knock down power in close quarters, I am considering a piston drive 300 blk ar for how modular it is. Takes all the same .223 parts minus the barrel of course. Pretty much the same round as the ak and can be reloaded from the hundreds of rounds of spent .223/5.56 I already have and reload.

I am getting off track of course, but I was considering buying and trying a piston kit on my girlfriends new rifle. When the time comes I'll put a few hundred down range and do a review on it for all of our reference. And maybe, if someone already has a conversion kit let us all know the dirty! If you have one of the 2k pof, or lwrc rifles, I don't want to hear it!

Imrahil

Piston kit systems were designed for a very niche market. Namely people who wanted to shoot their rifles for thousands upon thousands of rounds without cleaning it, and usually hundreds of rounds without giving it much of a break. By adding a piston it stopped the hot gas from dropping carbon fouling into the chamber, reducing chamber heat and decreasing fouling. Basically the only person that this was ever designed for is soldiers.

I have never understood how they can claim accuracy increases. Adding extra weight that moves back and forth simply increase vibration of the platform, increased vibration (that is not caused by the harmonics of firing) decreases accuracy.

Less fouling is another claim that I have never understood because no matter what you do to the action you will never be able to change the amount of fouling without changing the ammunition. All of that carbon must go somewhere.

Honestly, in my experience you should just spend the money on a nickle boron bcg and skip the piston kit that adds weight to your system. I have never handled a piston rifle that balances correctly, they all become front heavy because of the added weight.

Just a little maintenance will do the same job that the piston kit will without having to increase weight, slow down operation, or (in my opinion only) decrease accuracy. Add a nickle boron bcg and trigger group and you have zero reason to go with a piston kit. Add some great lube (I always use and suggest Militec-1 and KG-10 Micro Dry Moly) to your cleaning regiment and you have an action that is slicker than owl shit. The best part is that nickle boron can be cleaned by simply wiping it with a rag, add a silicon rag to it and it becomes easier. If you do treat it with Militec-1 it becomes even easier.

One other answer to your question, because it makes money. If someone is willing to buy it, someone is willing to produce it. That does not mean that it is worth your time and money. I've seen many people buy parts that were useless or even dropped the effectiveness of their platform, and all because they believed the marketing bologna. Remember that marketing is their job and is damn near a science. Not everything in this world is useful to anyone except the company that makes it, and often its only use is to pry your money from your hands. Heck, I can't tell you how many gimmicky things I've bought for firearms because of that, but you live you learn.

Of course, some out there just want the latest and greatest. That is fine, it is their AR and their money. As long as they are happy with their firearm then who am I to say different?

I personally do my best to stay away from exotic systems. If something does fail me I want to be able to open up my box of spare parts and grab the one that I need, or even drive to the local shop and pick them up. You can not do that with these piston systems.

JeepApex

AK versus AR being "better than the other" is such an old and annoying argument. You will find someone who says the AK is better for every person who says the AR is better. What it boils down to is operator preference. Ak's are no more reliable than the AR. They are EQUALLY as reliable if properly cared for. Treat your AK like shit, it will treat you like shit back... piston operated or not, guns are MACHINES. Machines WILL BREAK DOWN without proper lubrication. It's a common misconception that you can go millions of years without lubing an AK.

As another poster stated, the piston systems fit a very niche market. It's for the guys who don't like to break finger nails and get a little carbon all over their manicured hands. Are there benefits to the piston system? That depends on operator preference.

As you can probably read from my posts I'm not a strong proponent of the piston crowd. The DI kits work. If it ain't broke... don't fix it. You got yourself a damn fine Colt. No need to go destroy it by adding unnecessary weight and junk. Honestly, I don't even feel you need to get a fancy BCG. Your kit WILL WORK. Just lube it PROPERLY with GOOD lube... don't use remoil or cheapo walmart crap. Buy Slip2000 EWL, Breakfree CLP, or FrogLube. Save that $300 on ammo or put it towards a decent optic.

end rant.

powrsurg

Its clear to me that changing to a piston system is not the right move. Thank You! I love my rifle. The first round I shot jammed because I didnt lube it before bringing from the store to the range. Since then, I have put well over 2000 rounds through it and no jams have occurred. Im putting mostly russian crap through it, and its reliable beyond my expectations.

I had read an article that said the ACR uses a piston system as a way of solving weaknesses inherent to the M16/4. Seeing that piston conversions are somewhat cheap, I figured what the hell. That one article is really what got me thinking.

As far as which is better the M4 or AK, I would say pros and cons exist with each. FIrst the M4 was designed for a well trained soldier. The AK was designed for an insurgency / guerilla force.

The .223 / 5.56 is a more accurate round and can travel accurately to longer distances.

The 7.62 is a much deadlier round and less ammo needs to be fired. Again, this works well for an insurgency army.
I also have read countless stories about vietnam and how the M16's would get fowled constantly whereas the AK handled the jungle and more recently, the desert extremely well. The M4 not so much so.
SO unless my knowledge is completely off, I would say the AK has a slight edge if shooting distances no greater than 100 yards. It can run dirty, shoots powerful and cheap ammo and the rifle itself is cheap.

As you can tell by the truck I drive, I like to modify things with the hopes of making them better. THanks for stearing me away from a huge and costly mistake.