Jump to content

Benelli M4 -- Magazine Tube Removal Pictorial


Recommended Posts

Hi all:

I figured I'd compile a basic pictorial for the new users regarding the removal of the magazine tube to install a full length tube. I had snapped some photographs back when I did mine that might help some of the newer guys to get the job done.


This tutorial will span several posts due to the number of pictures posted limit that this forum has.


First, here is a schematic of the weapon we will be working on.



To begin, unload the weapon's chamber and empty the magazine. Field strip the weapon. Remove the trigger pack, bolt carrier group, barrel assembly and even the stock. You should be left with a receiver with its recoil extension and its magazine tube attached.


Now, disassemble the magazine tube #122. Unscrew the tube limiter. The tube limiter is not shown in the schematic. The factory bolt handle #39 can be used to pull the spring retainer cap #72 from the end of the magazine tube #122. You may also use snap ring pliers. Be careful when removing the spring retainer cap #72, the magazine spring #79 is under spring tension. Cup your hand over the end of the magazine tube #122 as you remove the spring retainer cap #72 to capture the magazine spring #79. Once the magazine spring #79 has been removed, tip the receiver downward to allow the magazine follower #76 out.


Now, I like to put my receiver in a vice to make the job much easier on myself. I used balsa wood strips this time between the receiver and the vice. I avoided using a rag because I was worried that it might start a fire when heating the receiver.




This was probably overkill since the heat stays pretty localized to the area of the receiver with the threads in it. The rest of the receiver will get hot, but nowhere near the temperature required to start a fire.


You do not want to squeeze the receiver very tight. Aluminum receivers can twist rather easily. If done right, you won't be applying much torque to remove the magazine tube anyway.


I flushed out the receiver with BreakFree Powder Blast solvent to remove much of the oil inside the receiver. My concern was that it might start smoking during the heating process.


At this point, I reinstalled the trigger pack and the bolt carrier group. The reasoning was the trigger pack might add some rigidity to the receiver. Having the bolt carrier group present won't hurt, but probably won't help much either honestly in hindsight.

Link to comment
Share on other sites

Now, get out your heatgun. I bought a cheap unit from Home Depot. It is a 1000 watts and does the job very well. It actually was enough to remove the receiver extension from my M4.




You want to apply your heat at the base of the magazine tube #122 and on the aluminum receiver. The heat will penetrate into the threaded area of the receiver and begin breaking down the factory locktite. How long you will have to apply heat will depend on how much locktite put on your weapon and how strong of a heatgun you have. Typically, it takes about ten minutes before you will see the area around the magazine tube and receiver start to smoke. This smoke is the locktite melting and burning off.


You should twist from the end of the magazine tube. The tube will be warm, but shouldn't be too hot to touch.


Attempt to twist the magazine tube from the receiver every few minutes. You do not need a lot of strength. The goal is to break the locktites bond, and the tube will simply unscrew with very little effort. If it still won't budge, keep applying heat in five minute intervals. Do not use a strap wrench. You will be applying a dangerous amount of torque with it.


In the multiple M4's I've done, the tube will slowly start to untwist like if you were twisting through thick glue. Usually it will stop turning after about 1/16 of a full rotation. So keep applying heat. This will repeat itself several times before the tube will finally fully unscrew.



Link to comment
Share on other sites

As you can see, the receiver will look nasty once you get the magazine tube removed. The white powder is the pulverized locktite. Flush the receiver out with BreakFree to remove the bulk of the debris. Use acetone and a wire brush to remove the remaining locktite from the receiver threads.




Here is the magazine tube #122 removed from the receiver. You need to recover the Forearm Retaining Band #69 (gigity). The Forearm Retaining Band #69 is a slip fit part that will simply pull off of the Magazine Tube #122.



Link to comment
Share on other sites



Now that the removal is complete, it is time to reinstall your new full length magazine tube. Test fit your magazine tube into the receiver. Make sure that the threads are clean and they do not hang up during seating. You may reapply locktite to your new magazine tube if you wish. I personally forgo this option so I can clean the weapon better. I simply tighten the tube down very tight by hand. It is much easier to clean the receiver if you can remove the magazine tube.


Once you have tightened your new full length magazine tube. Insert your follower down the magazine tube. Then install your magazine spring. Then compress the magazine spring, and install the Magazine Spring Retaining Cap. This is best to do with snap ring pliers.


Reassemble your weapon and function test it. Ensure that the weapon can now seat seven 2 3/4" shells or six 3" shells in the magazine tube.


All in all, this job sounds harder to do than it really is.

  • Upvote 1
Link to comment
Share on other sites

Now for some full length magazine tube porn. This is a carriercomp titanium magazine tube. I had a factory Benelli extension previously, it sucked dong compared to the full length tube. It was heavier. Not 922 compliant. Finish was terrible. It would loosen during shooting sometimes. Harder to install the spring with the extension since the spring would hang on the joint between the two tubes. The factory extension was expensive too. I bought mine for 70 dollars new back in 2004. I sold it used in 2009 for 150 dollars.



Factory Benelli Extension



Carriercomp Titanium full length Magazine Tube.

Edited by StrangerDanger
Link to comment
Share on other sites

Awesome pictorial, but it might scare some people.


2 hot-pads on either side of the reciever, hold it between your knees, heat the mag-tube at the base and the part of the reciever that is directly holding it, and twist the mag-tube free with your hands. Put some CLP inside the mag-tube at the base, and when it starts to smoke out of the tube, you have it hot enough. Twist it as much as you can, re-heat, repeat.


Tutorial above is very good, but don't let it intimidate you. The above few lines sum the operation up. It's what I do when they CAKE! the lok-tite junk they use on there. If they only use a little bit, I will just glare at it for a few minutes and it un-screws with ease.

Link to comment
Share on other sites

good job on that stranger. unobtanium you must have had a ridiculous heat gun i had a 1200 and i heated the base of the tube at least 20 minutes and it never turned i then i gave up and heated the receiver for about 5 all over and it just almost twisted out like butter..

Link to comment
Share on other sites

good job on that stranger. unobtanium you must have had a ridiculous heat gun i had a 1200 and i heated the base of the tube at least 20 minutes and it never turned i then i gave up and heated the receiver for about 5 all over and it just almost twisted out like butter..


Heat gun is cheap. Has "high" and "low" setting. Identical to the one pictured by Stranger. I alternated between the receiver around the tube, and the base of the tube itself, blowing the hot air on the junction between the two. When the CLP smoked, I stopped and twisted. When the turning stopped, I heated it up again. My tube had about that much and half again as much lok-tite on it as Stranger's did in his pictures above.


What you have to understand, Bello, is that I embrace the bachelor lifestyle.The heat-gun was almost an afterthought :)


Edited by Unobtanium
Link to comment
Share on other sites

  • 9 months later...

The pictorial was interesting and helpful.


I'm aware that there may be other methods for removing and replacing the stock magazine tube on the M4, but this is the one that worked very well for me. The key was patient application of heat, I was probably a tad too conservative for fear of overheating. My advice: be patient and take your time. The instructions for replacing that come with the Carrier Comp tube worked perfectly well.


Please be aware: You will hear from others on this thread, no doubt, that they have a "better" way, and will advise the use of heat sinks, or other methods. Don't be put off, or intimidated, by the various opinions or allow yourself to get to the point that with so many "experts" sharing opinions, it is not something you feel like you can do by yourself. Just follow the instructions that come with Kip's Carrier Comp tube, and you'll be just fine. If I could do it, frankly, anyone can.


Interesting to notice that the residue on his shotgun was green, mine was red. Wonder what the difference was? Perhaps different locktite substance?


Edited by Amsdorf
Link to comment
Share on other sites

Awesome... thanks, I havent tried removing my stock yet since I bought it. I guess I will try an remove it before my CC Tube gets here. I am going to purchase all of the necessary items to help with the install (heatgun, snap ring pliers, ect.).

Im going to follow all of your instructions to a "T"! Thanks !

Link to comment
Share on other sites

Zeke, yes on the snap ring pliers!! Will make your life a lot easier.


Can't wait to see the results of your install, enjoy!! It's fun.


Make sure you get this kind of snap ring plier set:


http://www.sears.com/shc/s/p_10153_1...d Toolsmv=rr


The snap ring in the tube needs to be squeezed together to remove and reinstall, so if you get a "dual purpose" snap ring plier, you'll have more options.


I got mine at Home Depot, Vice Grip brand, not very expensive.

Edited by Amsdorf
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Unfortunately, your content contains terms that we do not allow. Please edit your content to remove the highlighted words below.
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...