Modified Marushin XM177E2 => AR15

Just having some fun with my model XM177E2.

Base model XM177E2 fitted with Colt Mfg. parts, KAC RAS, Surefire etc.



Modified Bolt




Marushin gave me an unthreaded mag release so I had to do it myself with pliers.


4 position receiver extension


The product. Keep in mind the bolt release is missing

Wow, a stunning model. Can you tell us details about your work? It looks like the upper receiver is not the original, modified marushin part. Does the modelgun still "fire" Marushin carts using plug fire caps?

Wow! And "me too" regarding MadMike's questions!

Very, very nice

I'd also be very interested to learn more about your conversion. If it's still a PFC cap firer, have you been able to improve upon Marushin's firing performance

Upper assembly looks like the MGC one to me ..can`t see any screw holes for the marushin ejector part

DOC

Sorry for the late reply, forgot my password for a bit.

MadMike wrote:

Wow, a stunning model. Can you tell us details about your work? It looks like the upper receiver is not the original, modified marushin part. Does the modelgun still "fire" Marushin carts using plug fire caps?

Yes, the upper is not the original. The upper receiver assembly is Colt and the rails are real Knights Armament. I am still working on trying to get the model to fire the cartridges but it's difficult considering the feed ramps on the real Colt upper needs to really be modified.

Cerwyn wrote:

Very, very nice

I'd also be very interested to learn more about your conversion. If it's still a PFC cap firer, have you been able to improve upon Marushin's firing performance

Unfortunately, no.

DOC wrote:

Upper assembly looks like the MGC one to me ..can`t see any screw holes for the marushin ejector part

DOC

Nothing MGC on it. The lower receiver and internals are all Marushin. Everything else is Colt Mfg. (A2 grip, 30 rd magazines, buttstock, upper, takedown pins, etc.)

Keep in mind that I am in the US so it's fairly easy for me to get these parts. Though in the state I live in, gun laws are still very strict.

I am really impressed! Did you manage to use the original Marushin stock tube (buffer extension)? Judging from the photo it looks like the Marushin tube. Did you have to rework the stock then? Or were you able to install a real Colt buffer extension? I am quite sure that would mean new threads in the lower Marushin receiver.
Sadly I can not get real Colt parts for my models like receivers and bolt carriers and so on, but I am allowed to use parts like stocks, grips, handguards as long as I can make them fit, which is not easy at all. Anyway I thought that Colt M4 style flat top uppers are still highly sought after in the US, so i am even more impressed you used one for a modelgun.

I kept the original Marushin receiver extension. I lined the inside of the Colt buttstock with double stick velco so that it will fit snug onto the extension. The Marushin receiver extension has a smaller diameter than a real extension (so you can't put a real bold carrier). I parted out the model a year ago and I've been trying to get rid of the Colt upper assembly ever since!

MadMike wrote:

I am really impressed! Did you manage to use the original Marushin stock tube (buffer extension)? Judging from the photo it looks like the Marushin tube. Did you have to rework the stock then? Or were you able to install a real Colt buffer extension? I am quite sure that would mean new threads in the lower Marushin receiver.
Sadly I can not get real Colt parts for my models like receivers and bolt carriers and so on, but I am allowed to use parts like stocks, grips, handguards as long as I can make them fit, which is not easy at all. Anyway I thought that Colt M4 style flat top uppers are still highly sought after in the US, so i am even more impressed you used one for a modelgun.

I'm new to this forum but it has inspired me to do a similar conversion on a damaged Marushin XM177E2. So far, I have converted it to a flat-top by sawing and filing off the carry-handle and attaching a rail. I have also fitted a Magpul fore-end and have an MOE stock and MIAD pistol grip on order. I have also fitted a receiver end plate sling swivel. At present it still has the XM177 barrel and tatty plastic suppressor/flash eliminatoe, but I hope to get an A1 barrel when Kevin at MGC can find one. It previously had an A1 barrel, but it was broken off, destroying the threads on the section of barrel under the handguards. I replaced that, courtesy of Kevin, and several other parts, and also fitted a dummy gas-tube which can be seen through the vent holes in the top of the handguard. .

One problem I have is that the Magpul handgusrds tend to turn when any twisting force is applied to them because the Delta ring can turn. This is not only bad iun itself, but it appies extra stress to the attachment of the gas-tube. I wonder if any members have helpful advice to offer on this.

I hope to post pics when the conversion is further along and I have figured out how to post them.

It just looks great
Congratulations

where is the large magazine from ?

Here is my XM177E2 conversion, so far. It began as a Marushin XM177 which had been given an A1 barrel. It had suffered some rough treatment and quite severely damaged. The main problem was that the barrel was broken off, causing stripping of the threads at the endcap. Also the détente pins holding the take-down and pivot pins in place were missing.. I had more or less abandoned it until I saw Brian’s conversion, and got inspired to do a flat-top conversion.



The conversion to flat-top was simply carried out by hacksawing off the carry handle and filing the receiver top perfectly flat, and attaching a rail with epoxy and pop-rivets. It seems pretty robust. I converted the buffer tube to take a 4 position stock, just as Brian di, by drilling two extra holes.
I have fitted my gun out with Magpul MOE handguards, pistol grip, and buttstock in Flat Dark Earth, and a black Magpul flip-up rear sight. I also fitted two short lengths of Magpul rail (also FDE) on the handguards, and a Magpul sling ring. The vent holes in the top of the handhuard would expose the lack of a gas-tube, so I made a dummu one ut of two silver coloured biro refills of the right thickness. This can be seen in the detail below.



I got a replacement for the part of the barrel between the chamber and the end-cap from modelguncollector.com, (MGC) and refitted the original XM177E2 barrel, complete with miserable plastic flash hider/suppressor. I also fitted an Aimpoint Comp M2 replica red dot sight and a GI sling, modified with H&K hooks. The sling is currently attached to the original forward sling swivel and to an conventional rifle sling swivel which I attached to the receiver end plate. There is a “no name” flashlight attached to the left side rail. This morning I replaced the Aimpoint with an EOTech 552 clone (see below).





I am still waiting for the détente pins and their springs from MGC, and the take-down and pivot pins are held in with bits of wire, not very securely, for the time being! I am also hoping that MGC will be able to find me another A1 barrel, so it will ultimately look like a real AR15 with 14.5 inch barrel. There is still a good deal of work to do, when the pins and barrel arrive, which may be some time. Main things are refinishing the metalwork, which shows a good few battle scars (and traces of epoxy on the receiver!), and securing the handguards, which move when any twist is applied to them. I think (hope) a drop of Loctite where the top handguard joins the endcap may do the trick, but this will make its attachment more or less permanent, and I don’t want to do this until the new barrel is attached. The lower handguard must be kept removable for cleaning of course.
I am also trying to file an extended charging handle latch to fit, but this is a work in progress.
My apologies for the quality of the photos, but it’s cheap camera and very inexpert photographer!
I

At last the conversion is finished! My XM177 is as much an AR-15 as it can be. I have already described much of the process, but since my last report those détente pins arrived, so it is now held together by more than faith alone! I also have found an A1 barrel, so the weapon’s profile is now that of an AR-15 with a 14 inch barrel and fixed muzzle attachment, an AR-15 variant which is fairly common. In the USA, this is the shortest it can be without being a “short barrelled rifle”, subject to extra regulations and taxes. Also, of course, it is the length of the M4 barrel, though it doesn’t have the M4 profile.
I also sprayed the metal parts with Krylon flat black comouflsge paint, after scraping off the odd splash of epoxy from the receiver, degreasing it, and roughening the surface with wire wool. At first, I was disappointed in the result. It looked as though it had been left up the chimney and got covered with soot! However. I left it for a few days and then scrubbed it again with wire wool. This was supposed to be the first step in removing the paint, but I was surprised to find that the metal had returned to its original colour, as when it was new.



And, for comparison, the Real Thing! The only obvious differences are the bayonet lug (I was taught to call it a "sword bar! ), the M4 profile barrel on the real thing, plus, of course, the markings, which are still XM177E2, and the selector lever. The internals are still "model gun, of course.

As I mentioned, I fitted a Chinese EOTech clone. It is correctly marked, except for the EOTech logo, has the yellow laser sticker, and it looks very like the real thing. It seems to be quite robust, and allows a “lower third” co-witness with the iron sights, as it should. For a model gun, which cannot fire live rounds, it is perfectly adequate, but it is a definite no-no for the real thing! The lenses are not fog-proof and it shows a light on its fore side. I also doubt if it would hold zero under the vibration of recoil. The brighness settings are also pretty ineffective. It may just about do for airsft use in daylight. Needless to say, the “NV” button does not render it night vision compatible, but changes the reticle from red to green.
I had a last minute struggle with the charging handle latch. I tried (am still trying) to make a real steel UTG extended charging handle latch fit. It was too thick to fit the slot in the charging handle, and turned out to be the wrong shape, when filed to thickness, to pivot as it should. I’m still working on this, but in the process, the tiny pin which holds the latch in place flew away and got lost. I replaced it with a panel pin, cut to length and with the head filed down to sit flat on top. However. repeated use of the charging handle led the pin to jump up just enough to prevent the bolt fully returning to battery. I solved the problem, eventually, with a drop of Loctite, and so far, it hasn’t moved.
This morning a Magpul MS-3 Multi-Mission sling arrived, so the conversion is as complete as I can make it for the time being. I have to keep it away from my front windows to avoid frightening the neighbours and bring down the police armed support unit!
Finally, I am happy to report that it shoots! I fired 20 rounds from two magazines, on single shot; first “in slow time”, and then in single shot rapid fire, with no FTFs. I have not tried to fire in auto, as this would not be possible with a civilian AR-15. I’m looking for a way to fix the selector switch so c has only two positions: Safe and Single Shot.
Just in case the cops are watching, the two "live" rounds contain neither propellant nor primer.

Horsemarine, that's a better modification than mine! Stunning model. Have you tried to get your hands on a 30 round magazine? You can always buy an airsoft magazine for show.

Thanks, Maverick. Since I posted, I have got hold of a 30 round mag. I'm told it's a Marushin model, but, though it has a spring of "model gun" strength, its follower fills the mag fore and aft and there is no "filler" to allow for the Marushin bulletless cartridge's shorter length. I suspect it may be GI mag with the spring changed. So far, it has fed OK, but this is under "range", rather than "combat" conditions.

I'm afraid my photos are pretty abysmal. Do you have any pics of yours?

A little late, but I wish a happy Easter to all our readers.

Horsemarine, yes I do have pics. They are on the first post of this thread. I can't access my old account so I had to make a new one. Here is another model I just finished though:
https://mp40modelguns.forumotion.net/t3841-mgc-m4a1

Your magazine is most likely a true and rare Marushin 30 rounder. They had the full legth plastic follower but a weak spring.