StrangerDanger

Normal. They free float. Even when the bolt carrier is forward, there is a small amount of movement.

The lighter a weapon is, the faster it will be in a close quarters area of operation. A lot of people just sit at a range and shoot at stationary targets in great lighting. If so, weight reduction won't matter very much. However, if you plan to carry the rifle for miles slung, you'll notice a half pound drop. You will be faster when bringing the weapon onto target. It will be easier to aim for several minutes at w time off hand. Cutting weight from the muzzle is a great way to shift the balance to the rear. Remember that all that weight at the front is leveraged against you. I avoid mounting anything on the side rails in order to preserve balance and to avoid having obstructions that will rack your shins or upper leg when slung. Top and bottom mounted lights are great to avoid this. My current light of choice is a 12 o'clock Surefire X300. It weighs 4 ounces and is obstruction free. I see absolutely no value in having a heavy barrel on a semi automatic carbine.

I was in HellA to meet with a machinist about making a US Made set of pistons for the Benelli M4. The barrel being cut down to a low profile is for weight reduction. They put the barrel in a lathe and cut the outer diameter to .625". Your barrel is probably .750". The difference doesn't sound like a lot, but it makes a huge difference. I didn't notice any reduction in accuracy in mine. However, I'm not a benchrest shooter. Hbars will handle heat better. I doubt that would be much of an issue with the fixed magazines in California. My barrel was the same length as yours. They cut it down to 14.5" and pinned on a flash suppressor so the overall length is 16". If flash suppressors are illegal, then pick a compensator. Are flash hiders legal in California? I'm not really up on all their BS laws. Here is adco's website. http://www.adcofirearms.com/

Everyone is on Xmas break. Nice job with the Benelli. I agree the Surefire is heavy. I never liked the forward vertical grip myself. The broom handle concept is lacking to me. I do like the navigation lights in the unit though. As someone who spends a lot of time armed in the dark, low output nav lights are a nice touch. What I would recommend is that you have the barrel profiled down to .625" before and after the front sight post. Have the barrel length cut to exactly 16" with a comp pinned in place to conform to State law. This will cut 10 ounces of weight off your weapon. Have a low profile gas block installed at that time so you can add a flip up front sight and remove the obstruction from the optics FOV. Adco could do all of this in about 2 weeks. The balance of your weapon would greatly improve. It would help offset the weigh of that light package and help shift the center point of weight back towards the mag well. I chickened out taking my complete Benelli to California earlier this week. I ended up only taking the barrel assembly in order to spec out the gas pistons.

There is no dedicated forend. The Surefire M80 rail system is okay, but what I found was the light obstructed my hand when mounted. The M80 is around 225 bucks also. They're not real easy to find sometimes. The SideArmor is often on sale and typically costs around 300 shipped. You have several options for what light to use. Consider how it will be activated before you make your choice.

No. A light will block your iron sights. If you need a light, the best option currently is the SideArmor rail.

CarrierComp Titanium magazine tubes are by far the best thing available. Chances of a better combat designed Benelli are slim. The M4 will allow you to mix dram loads like a candy cane if you wanted with no reliability issues. There are no gas system adjustments either. The system simply adapts to what it needs to operate. Excess is vented. 3" shells should fit 6 rounds if I recall in the tube. It might be 5 though.

The Saiga has questionable reliablity with low base rounds. The only one I would want is the 8" barreled style. Anything else, I'd rather the M4. If you want a pump gun, completely different animal. Get an 870 or a 590.

Mine is a SMOS billet lower. They're sold as LaRue lowers now. I prefer my older one without the giant Texas logo since I prefer subdued logos. If I was buying a lower right now, I'd get a Tactical Innovations billet lower receiver. The fit between my SMOS and the LMT was very tight. They break in together over time. The fit is so tight that there is absolutely no play without using an accuwedge or similar devices. I'd have to tap the rear pin in while squeezing the upper and lower together. I prefer this to the sloppy fit of my old Colt. The hardest thing about the LMT piston upper is finding one for sale. What I often weigh is if the upper alone is worth what a ACR will cost next year, and would I rather a lighter weapon? A migration of my equipment to an ACR would probably shave a pound of weight and be a little more ergonomic.

Good idea about connecting with a college. If I have to buy another factory one, that is fine also. We'll use the best canidate we can find for the job being performed. Then see what the company has to say regarding wha method of heat treatment should be performed. I have a feeling that there is a variable heat treatment on the factory ones. I have snapped a factory piston in the past. So if we have the potential to over-build the piston, we will. Then, I'll do some real world testing on a set the fun way. Brownells wants 90 dollars each for a gas piston. That is with my discount. 115 without.

Pictures or it didn't happen.

It's hard to damage anything but plastic and wood with a heat gun. I might be careful of the camo finished M4 though. Leave the bolt carrier in the weapon retracted to the rear. It'll strengthen the receiver while you're applying torsional torque to the tube. You shouldn't need a lot of torque to twist it free. A firm two handed twist at the beginning is all. Anymore means the locktite hasn't given up yet. Pull the trigger group for easy access to the receiver. The tubes tend to twist about an eighth of a turn then stop. Apply more heat and try again. After a couple times it will break free and untwist fully.

Got a friend that can help? Two can twist easier if one secures the weapon. However, I think you need more heat. You can't hurt it with a heat gun, so roast it for 15 minutes.

Titanium won't work. Titanium is brittle, galls easily and is difficult to machine. Titanium is stronger than steel when both weigh the same. So in this case, stainless steel would be a better choice.

I grew up there as well. But moved to a free State in the early 90's. Best lifestyle change ever! Torrence can be a rough area. I'm sure Michael Vick would love it. Between dog and rooster (their real name is banned) fights, there is something for everyone. I agree that the heat treatment will be the hardest thing to perfect. I don't plan to do it, we plan to outsource the heat treating process to another company that can assure some level of quality control. Too hard and the pistons will shatter. Too soft and they will deform from impacting the BCG. I'm looking at finishes also. I think Robars NP3 would be the best. Easy to wipe clean and self lubricating due to the imbedded Teflon. I spent some time looking at exactly how the ARGO functions. It isn't as much Elven magic as Benelli would lead everyone to believe. If you disassemble the ARGO system, and look down the threaded side of the barrel where the gas plug attaches, you can see the port that opens up to the barrel. It is easy to see why the 4 port models destroyed the BCG and snapped pistons. There isn't much gas regulation before the gas meets the pistons. Whatever enters the gas ports through the barrel is going to imping the piston. The gas plug will bleed off excess pressure after the cyclic action has occured. The end of the piston actually makes a poor seal against the gas plugs regulator. Chances are, most sissy loads won't even vent out the gas plug. The majority of the gas and suspended carbon will be channeled rearward around the loose fitting pistons. This is why sissy loads cycle slower than full house high brass loads. What is interesting is the 4 port version was unable to bleed enough off through the gas plugs to prevent damage. My guess is the initial spike of pressure was cycling the action before the ARGO had the chance to bleed the gas off. The reason that everyone says not to oil the pistons is due to the smoke you'll create. The oil will collect carbon deposits too. There is no benefit to oiling them either. The only contact points are polished smooth along theraised ridges of the piston.

San Pedro, where I'm originally from. Up for the holidays for a few days. There is a lot of talent there along the docks.

Hi, does anyone have any tech data on the Benelli M4 gas pistons? Such as what type of stainless steel they are made of? I don't expect to find blue prints of the pistons -- those are fairly easy to blue print anyway. I'm meeting with a machinist next week in Communist California to see about having US made pistons produced.

No difference really. Mesa's Urbino may offer some addition recoil reduction due to the intergrated limb saver pad.

I think it is mostly the weight of the MGI vs. the M2 buffer. The recoil pulse isn't as sharp with the MGI. I've heard others have had similar results with the heavy buffer that Spikes Tactical makes. A bit cheaper too.

I never noticed any difference in recoil either. There isn't much to begin with since I use a MGI buffer. It is absolutely much cleaner to operate and cooler. I shot several magazines full in a couple minutes, I then felt the BCG through the ejection port. It was barely luke warm. The UBR has a compartment, but anything you put inside fits loose. So batteries will rattle unless you wrap them in a cloth or something. I stick ear plugs in there.

Here are the Ergo wire loom ladder rails. http://farm3.static.flickr.com/2695/4117045418_79279e57a1_b.jpg In the large photo, you can see the skateboard tape I used to cover the exposed wire along the stock. I used the small squares sold by Rainier. They were developed for the Magpul Pmags. This worked better than expected. The only section I don't like is around the rear sight. Overall, I can control my lights output exactly like a set of Crimson Trace Laser Grips.

Here is the Scout Light parallel with the barrel. Note how obstruction free the handguards are. As Martha the Nazi Stewart would say, "It's a good thing." Here, the rubberized grip was slipped back over the tape switch. You can barely tell it is there. Before I finished it up completely, I filled the portion of the stock I undercut to seat the switch higher up with epoxy to add support. The wire is pretty much in there forever unless I want to cut it out. The added strength was worth the trade off. Beneath the tape switch, I have velcro. This keeps the switch in place while you slide the rubber grip over it. You can adjust how sensitive you want the pressure switch by placing things in between the rubber and the switch. The edges of the switch can be raised with thick wire or wooden dowels to build a bump guard around the switch. We're talking .1" diameter material. That way if you lay the weapon down or have it slung, chances of it being accidentally turned on are reduced.

Basic parts. Disassembled buttstock and so on. The wire routed to the Surefire Scout light along the right side of the SideArmor top rail. At first, I just ziptied it to a ladder rail. Later on, I went to the Ergo Grip wire loom top rail covers.

Here, the wire is just freely laid along the top of the stock and onto the receiver. Here, the switch is mostly fit into place.

Here, I used a dremel with a pen attachment to cut the shape of the tape switch out from the stock. Remember that the pistol grip itself is hollow, so you can only remove so much material. For peace of mind, I filled mine with epoxy and glued a strip of plastic or a piece of metal (I forget) against the side I was cutting against for support. If you look at the tape switch, you'll notice where the wire enters the pad. This portion of the switch does not activate the light. So I wanted it pushed up under the overhang of the pistol grip as high as possible. I wanted the activation of the light to be under my middle finger and ring finger. Not at my pinkie. So I cut under the top edge of the stock so the switch and the wire would tuck up under. You can see where I milled a wire groove along the back of the grip and into the .5" hole in the stock. Placement of this hole was important. You do not want to impede where the receiver extension slides in. It must be .5" because that is how big the head of the tape switch connector is. You must remove the butt pad from the stock in order to route the wire through the interior of the stock. There are two small holes on the rubber stock. A philips screw driver will push into them and allow you to remove it. Placement of the top hole was key also to minimize how much of a wire groove must be cut. Careful not to impede the receiver extension again.