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Disassembly Guide for the Benelli M4 ARGO Gas Plug. *Note. Most users will never need to perform this maintenance operation. The ARGO system is self cleaning and is designed to limit the amount of carbon that can build up within the ARGO gas plug. This informational is mainly for users who are troubleshooting a problem, clean up after submersion in salt water, or stripping the assembly down for coating or performing a high round count tear down, ie: 10,000 round break down. Typically, this is a task only performed by an armorer. The ARGO plug is composed of six parts; #89 -- Gas Plug O-Ring #90 -- Gas Plug #91 -- Gas Plug Pin #92 -- Gas Plug Cap #93 -- Gas Plug Spring #94 -- Gas Plug Spacer The ARGO plug itself is a relatively simple design. The Gas Plug Cap, Gas Plug Spring and Gas Plug Spacer are held into the Gas Plug by the Gas Plug Pin. The Gas Plug Pin is a solid pin that has milled ends that act as an alignment guide to prevent the pin from coming out on its own. The cap, spring and spacer under spring tension when held into the body of the gas plug. In order to remove the Gas Plug Pin, tension must be removed from it. To remove tension from the Gas Plug Pin, I used a Magnabit 080-430-435WB Ruger Clamp Screw Bit. This bit is notched in the center and allowed the outer edges of the bit to pass around the Gas Plug Pin and seat against the Gas Plug Spacer. I then placed the Gas Plug assembly and the bit into a vice and gently squeezed the bit and the Gas Plug together. I watched the Gas Plug Pin carefully to see when it began moving. Once the spring's tension was removed from the pin, the pin centered in the hole and was driven out with a Starrett drive punch. The assembly was then removed from the vice. The bit is a very tight fit, so it will take some effort to pull the bit free. Once removed, the Gas Plug Cap, Gas Plug Spring and Gas Plug Spacer will pull out easily. These parts will be extremely dirty. I recommend soaking the parts in solvent for a while before hitting the parts with a wire brush. On my assembly, I used no less than thirty Q-Tips to clean out the carbon inside the body of the Gas Plug. You will also notice that the spring is coated by some sort of heavy grease. After you have cleaned the parts, it is time for reassembly. Apply grease to the Gas Plug Spring. Insert the greased spring into the Gas Plug Cap. Insert the Gas Plug Spacer into the Gas Plug Spring. Seat these three parts into the Gas Plug. Re-installing the Gas Plug Pin can be difficult since you need to compress the spring. I found the best way was to simply get the pin started. To do this, put the Gas Plug on a hard work surface. With a punch, press firmly down against the Gas Plug Spacer while pushing the Gas Plug Pin into its hole. You'll likely only get the tip in since your punch will interfere with its insertion. Take the assembly to the vice, and press the pin in approximately 80% of the way. You'll notice as you press it in, the pin will be pushed out of alignment away from the Gas Plug Spacer since it is under spring tension. Now, use the Ruger bit and insert it through the Gas Plug to compress the spring again. Squeeze the assembly in a vice until the pin aligns with the hole. Use a drive punch to tap the pin the rest of the way in to the Gas Plug and be sure it is centered. Remove the Gas Plug from the vice, and remove the Ruger Bit to remove spring tension. As tension is removed from the Ruger bit, it will transfer to the Gas Plug Pin. As this happens, you'll see the pin push out of center alignment with the hole, and press against the outer edge of the pin's hole. Below are some pictures to help you visualize the task. Whatever you do, do not just try to drive the Gas Plug Pin out with a drive punch without removing spring tension first. If you attempt this, you'll either break your punch, break the Gas Plug Pin or worse, damage the ARGO Gas Plug. Once you price out how much a replacement plug costs, you'll really be crying if you do that.

Gave it a try tonight. Fully disassembled the ARGO plugs and cleaned them up. They are pretty filthy in there. I took some pictures for a pictorial for posterity. Be advised, this job requires some specialized tooling to get it apart and reassembled. Also, the spring inside of the unit is heavily greased. So users soaking parts should be wary of degreasing the assembly. I went through no less than thirty Q tips and a few pipe cleaners before the ARGO plug body was clean.

Which part was giving your grief? Putting the trigger assembly back into the receiver, or were you trying to reassemble the trigger group? Hope the package arrived today okay.

In the field, I agree they should never be disassembled. The reason I would like to take them apart is to coat the cup and body of the ARGO plug. I haven't tried, but it seems like if you compress the cup, you can drive the pin out. Once the pins out, the cup and spring should push out.

I mean take the plugs themselves apart. Removing the pin and taking the cup and spring out.

Anyone ever disassemble one of the plugs?

Whoops. You're correct about the modified choke. That is what I have as well. It will work just fine.

Slugs and buck work just fine for the Modified choke. Mine has handled thousands of each.

The SideArmor rail doesn't count towards 922® compliance. The SideArmor is nicely made, but it is heavy and will add some bulk to the receiver. When I had mine, I noticed this when carrying it slung.

Good info there. Thanks! A bottoming tap and threading to the middle from each side would work.

The FFT top rail is a good choice. I have a carriercomp, but they're virtually the same. The factory rail can damage certain mounts quite easily. Many people had issues with LaRue mounts. Upgrading is a good choice if you plan to mount anything to the top rail. Just be sure you torque the screws appropriately so you won't strip the fine threaded aluminum holes.

I believe Benelli intended to roll out a lot more, but the ATF crybabies ruined that. Kind of surprised they didn't just revert them to regular stocks and a reduced capacity magazine and keep on selling the style.

The seller is incorrect. I have from a reliable source that only 60 of the H2O's had entered into public circulation. The rest were sent back to Italy after the BATF threw a tantrum.

This came out really good. Much better than the Mesa cup.

Chalk this one up there with Hank Johnson (Democrat) thinking Guam would tip over if additional Marines were stationed on it and how a Peggy West (Democrat) would support Arizona's immigration law if only they shared a border with Mexico.

Most are after the 5.5 ounce weight savings with the carriercomp tube.

I have four tubes on order from 02/17/2013. Payment was taken about three weeks ago. Current lead times are about 12 - 16 weeks.

Thanks admin!

Only 200 posts.

Making your own limited rotation stops would be difficult. I'd use JB Weld. I'm not sure how long it would hold up though. The torsional force exerted by the QD connector is pretty high. I think you could hit the external edge with a file while rotating it and bevel the edge quite easily. I believe the cups are steel, right? You could hit them with some of that instant bluing after doing the filing. I looked at the grip core, if you grind off the feet and have a .510" overall length, seated up against the plate retainer will have approximately .200 exposed out of the grip. Roughly what I have now with the left side connector. If you were going to drill out the plate retainer, you'd have to go into it about .200", or approximately half way through the part. Then thread the remaining portion, and protrude into the opposite side for retention of the plate. Drilling out that part would not be fun. Mainly since the bottom of most bits are not flat. So you'd end up with something other than a flat bottom to seat the cup against. I don't think it's worth the headaches involved. .200" exposed is pretty good. It is certainly much shorter than the Mesa Tactical option. On the lathe, this would work out well, since you could leave a lip on it. Doing it by hand with a drill would be harder, but still possible.

You could build a poor mans lathe with a drill and just use a 'fatherless child' file to profile the OD down to 0.500". It doesn't have to be super precise. I'd probably epoxy the cup into the pistol grip to prevent rotation. Are you still planning to tap the plate retainer? I was thinking it might be best to drill into the plate retainer so the cup seats lower. You could probably get a flush fit doing that.

This sucks. How tall is the mount with and without those feet. Any machine shops near you? Turning the whole thing down to a specific diameter on a lathe would be easy. If the lathe was at my house or nearby, I'd offer to turn yours down. Drilling out to 5/8 is going to be a really big hole. You'll be drilling through that raised shelf above the existing hole. You could probably do the drilling with a wood boring bit due to the soft plastic. Your spade bit would probably work as well though. Just be careful going through into the opposite side with the pilot.

Sold......................

The QD socket for the CTR is probably the best route to go since isn't a permenant modification. It will be stronger than the cheek riser mount option too. You can easily flip the CTR one to try the connector on both sides to see which way works the best. Using this mount with the modified BLAM4 mount would work great for a 2 point sling.

A mount there is strong enough for civilian work. My concern is how the QD socket would feel with your face there. Or how the sling will bunch up at your face. What might work is putting the socket on the right side of the cheek rest. That way the whole left side profile is left alone. I usually connect my QD socket to the right side of my Ar15's in the back (right hand carry method.) this limits how much the rifle hangs away from my body. It also allows for more range of motion. This is theory for the m4 though, how it hangs and feels could be quite different and difficult to mock up prior to drilling into a part that is nearly impossible to replace.