MP5... PFC Project

Post by jay851

well,as none of the modelgun manufacturers have decided to make a pfc mp5 i am going to have a go myself.i have a tm mp5a4 which i will use for most parts but dont like the idea of a plastic receiver,so i have picked up a second hand g&g metal receiver.it will probably be quite a lengthy prosess which i will update whenever something else gets done,and will probably need help from you guys somewhere along the way

right, here is what i have done so far.

first,i managed to get a 'real steel' mp5 mag,which holds the marushin mp40/uzi cartridges very well.



the real magazine is of course a totally different size to the marui one so a fair bit of work has to be done in the mag well to get it to fit,as it is about 2mm wider.once it fits width ways,there is a fair amount of wobble from front to back which i will deal with later.





the part on the receiver where the hop up attaches has to come off in order to get the chamber and barrel on.



next i cut out the ejector port





as you can see this is just scraping the surface and there is a lot more work to be done.
i will keep you posted.

jay
_________________
currently own:
hudson m3a1 greasegun
mgc early type open barrel thompson smg
kokusai s&w military/police 4" bull barrel

Post by rizzo

wow! Good luck mate! What internals will you use? An MGC mac11 could work...

Post by jay851

hi rizzo
i'm going to build my own internals as close as possible to the real mp5.

jay
_________________
currently own:
hudson m3a1 greasegun
mgc early type open barrel thompson smg
kokusai s&w military/police 4" bull barrel

Post by Mark

Looks good so far Jay, As i am sure that you have noticed that the magazine catch is "thicker" in the area that it contacts the magazine due to the dimensionally thinner Marui magazine. This causes the magazine catch to stick out of the receiver when the magazine is inserted. The catches pad needs to be filed down a bit to match the thicker MP5 magazine.

No fair! your metal receiver is in two parts! The stock plastic Marui receivers are cast in two parts and then they are joined at the top by a one piece cast plastic top. This top is hard to remove with out breaking it so, i am going to do my Marui PDW conversion with out seperating the halves....

I am still using the MGC M16 components in a custom made sheet steel box that fits inside my Marui's plastic PDW lower receiver. The problem with most of the possible modelgun parts donors out there are that a good percentage of them are "open bolt" whereas, the MP5 fires from a "closed bolt" that tends to compound the problem.

Also, the shape of the MP5 tends to be a problem too as many possible donor submachinegun modelguns are the wrong shape square etc.
_________________
Wanted to buy: MGC Sten MK3....trades?(still)

MGC MP40 Marushin MP40 Nakata MP40 TRC MP40

Modelgun manufacturers, past and present:CMC,CAW,Hudson,HWS,LS,MGC(R.I.P. 1960's~2007) Marushin,Marui,Kokusai,Shoei,Tanaka and Western Arms

Post by Claymore

Yes it looks great jay and you are going to make your own bolt, wow you must have some good tools and machinery and ability. I wouldn't know where to start on doing a project like this i struggle to fix simple problems on existing modelguns never mind make my own.

I wish you luck (hey if this goes well fancy some commision work )

Post by Mark

Yes, the bolts are going to be the interesting part in our MP5 buildups as there are no existing modelgun bolts that will technically work as they either use the open bolt firing technique or they are the wrong shape/too small.

The bolts are probably going to be cast or pieced together in order to look and work right. The MP5's closed bolt system is the "problem" as the bolt must have either a firing pin or a movable bolt head/firing pin (like the MGC M16 series) The H&K's classic charging handle (The HK "slap") is going to be interesting too as the Marui MP5/PDW has a piece of ABS tubing with a screwed on zinc charging handle and a coil spring to pull the assembly back unlike the original MP5 that uses a spring loaded steel ball to lock the charging assembly in the forward position after the bolt has driven the charging handle assembly forward.

The extractors/ejectors are going to be another difficulty, as they have to be timed, angled as well as placed correctly in order to catch the cartridge. Some of the modifications needed to make these conversions work might not look 100% correct but, hopefully, they will be inside and not visable unless it's field stripped...
_________________
Wanted to buy: MGC Sten MK3....trades?(still)

MGC MP40 Marushin MP40 Nakata MP40 TRC MP40

Modelgun manufacturers, past and present:CMC,CAW,Hudson,HWS,LS,MGC(R.I.P. 1960's~2007) Marushin,Marui,Kokusai,Shoei,Tanaka and Western Arms

Post by jay851

hi all
just a quick update on the mp5.i've managed to make a bolt carrier and recoil assembly,and also the cocking tube.there was quite a bit of handwork to do in the receiver to get it all moving smoothly with no friction,but it runs pretty good now.the bolt carrier still needs welding up and i still need to make a bolt,but i am still unsure about the trigger mechanism.i was thinking of the idea of catching the bolt about 2mm before it ends its travel,then when the trigger is pulled it completes its travel to detonate the cartridge.does anyone know if any modelguns use this method?
mark was spot on about the cocking tube,i have managed to put a spring loaded ball bearing into the cocking tube to lock it forwards,works a treat.











jay
_________________
currently own:
hudson m3a1 greasegun
mgc early type open barrel thompson smg
kokusai s&w military/police 4" bull barrel

Post by Claymore

Jay i am seriously impressed, it looks like you are doing a better job Than the boys from Japan. You should do some translation into Japanese for them as i would think they would be very interested in what you are doing and how you are doing it.

Hope you make good progress.

Post by jay851

cheers claymore, i must admit i'm quite happy with how its gone so far,getting it to function and fire reliably is another matter
as for translating it, my japanese is a bit rusty how would i go about it.

jay
_________________
currently own:
hudson m3a1 greasegun
mgc early type open barrel thompson smg
kokusai s&w military/police 4" bull barrel

Post by Claymore

Wow~ Wow~ You are my idol...... How could you do this just by yourself!?

I am just wonder~ How come there still no any modelgun manufacturers want to make MP5?

Post by Claymore

Yeah, apart fom karate terms my Japanese is non existant i us babel fish and no you dont stick it in your ear.
Go here http://babelfish.altavista.com/ and it will translate for you, of course god knows what it translates into cos plastic from Japanese translets into rhinosorous (that does not look like the right spelling) i think,but it will probably get the jist of it across.

Post by Mark

Hey Jay,

That's looking great! Your bolt assembly looks interesting, is it all aluminum? or steel? If it is aluminum, i hope that you are great at using a TIG. What are you thinking using for a bolt head? As for the firing group, you really should copy the MP5's firing group as close as you can as making the bolt stop with in 2mm or so from detonating the cap sounds good but, i really don't think it's really practical. I don't really know of any modelgun that uses a system like what you describe so, i think that you are on your own.

You might try adopting the Tanaka Glock 18 striker assy as it somewhat resembles the idea that you have. However, the best method is to use an existing real or modelgun design for the firing group. The MGC M16's firing group can be used but it will take some re-arranging of the components to make it work correctly in the MP5 shell. I was thinking that i was going to cast my bolt carrier out of ABS resin but, after seeing your pictures, i may have to mill out a chunk of aluminum or a seriously lightened steel version. Also, i may have to find a zinc Marui PDW receiver replacement instead of the ABS receiver that i am using as the zinc receiver looks much better and adds to the weight.


By the way guys, the forum now has a built-in Japanese translation so, the translation from English to Japanese isn't required anymore...
_________________
Wanted to buy: MGC Sten MK3....trades?(still)

MGC MP40 Marushin MP40 Nakata MP40 TRC MP40

Modelgun manufacturers, past and present:CMC,CAW,Hudson,HWS,LS,MGC(R.I.P. 1960's~2007) Marushin,Marui,Kokusai,Shoei,Tanaka and Western Arms

Post by jay851

mark...the bolt carrier is made of steel but is still quite light,lighter than my mp40's heavy bolt. i guess the way to go is to stick with the real mp5's trigger group,i was just hoping to cut a few corners as it does look quite complicated,and everything has to be just so to make it function properly......a few dimensions would help greatly

jay
_________________
currently own:
hudson m3a1 greasegun
mgc early type open barrel thompson smg
kokusai s&w military/police 4" bull barrel

Post by Mark
Steel eh? How are you machining it? The Mp5's trigger group dimensions are hard to find but, i am sure that they can be found on the net. The dimensions of the real parts might not really help anyways as the scale just might be wrong...Cutting corners really should not be done on these projects even though they will take longer than we want to finish them.
_________________
Wanted to buy: MGC Sten MK3....trades?(still)

MGC MP40 Marushin MP40 Nakata MP40 TRC MP40

Modelgun manufacturers, past and present:CMC,CAW,Hudson,HWS,LS,MGC(R.I.P. 1960's~2007) Marushin,Marui,Kokusai,Shoei,Tanaka and Western Arms

Post by John

Hi Mark,

It should be mid-night at your place. Still so exciting with this project that makes you no need of sleeping ?

Anyway, whoever could succed this project will be the master of modelgun modification.

Post by Mark

Hi John, it's 11:35 right now. It's really not that late here and i don't really mind staying up to play with modelguns and post on the forums!
_________________
Wanted to buy: MGC Sten MK3....trades?(still)

MGC MP40 Marushin MP40 Nakata MP40 TRC MP40

Modelgun manufacturers, past and present:CMC,CAW,Hudson,HWS,LS,MGC(R.I.P. 1960's~2007) Marushin,Marui,Kokusai,Shoei,Tanaka and Western Arms

Post by jay851


have machined the parts at work on a fadal cnc vertical mill and a manual lathe,i guess my job does have some perks
the trigger group will be the challenge in my eyes,trial and error i suppose.

jay

Post by Mark

Yes, scratch building anything worthwhile is always on a trial and error basis I have an Emco CNC6 lathe at home but it has a bad tool turret board that needs to be replaced in order to get it back on line. But, i also have a manual lathe (actually, 4 of them) and a small mill. That's great that you have access to a CNC mill
_________________
Wanted to buy: MGC Sten MK3....trades?(still)

MGC MP40 Marushin MP40 Nakata MP40 TRC MP40

Modelgun manufacturers, past and present:CMC,CAW,Hudson,HWS,LS,MGC(R.I.P. 1960's~2007) Marushin,Marui,Kokusai,Shoei,Tanaka and Western Arms

Post by garyforce

hey jay.

just reading through the impressive work your doing.

i do have to say though.....and im sure you'll forgive me for saying this. but you best be careful ! ..... some bizzies could argue that your treading a very fine line with the firearms act ! they could accuse you of having the ability to "doctor" your modelguns.

im sure your aware of that and i very much doubt you or anyone on here would be that stupid ....but ...... just saying
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- Gary

Post by jay851

yeah i here ya gary, what i class as a harmless project,someone else may see as potentially dangerous.the gun is structually too weak to discharge any kind of 'real' ammunition without exploding,and im not sure that they could do anything just because i have the ability,as there are tons of people out there with the ability,but not dumb enough to actually do it.

jay
_________________
currently own:
hudson m3a1 greasegun
mgc early type open barrel thompson smg
kokusai s&w military/police 4" bull barrel

Post by jay851

hey jay
1st !

Quote :

the gun is structually too weak to discharge any kind of 'real' ammunition without exploding

i know that.you know that...and anyone with a brain nows that

Quote :

what i class as a harmless project,someone else may see as potentially dangerous.

this is were the grey area is ..... as i see it ..... you are technically making a firearm ...... the fact that it wouldnt discharge a round could be a bit irrelevant to the powers that be. :?
so i would just air on the side of caution ! especially in the neurotic anti gun climate we seem to have here now !

Post by Mark

Yes, claymore had the same feeling that i had the other day when you had shown the pictures of your MP5 project for the first time Gary..I thought that someone on the anti-firearms side might decide that you are making a dangerous weapon and report you to the authoritys..But, that is a incredibly remote possibility..
_________________
Wanted to buy: MGC Sten MK3....trades?(still)

MGC MP40 Marushin MP40 Nakata MP40 TRC MP40

Modelgun manufacturers, past and present:CMC,CAW,Hudson,HWS,LS,MGC(R.I.P. 1960's~2007) Marushin,Marui,Kokusai,Shoei,Tanaka and Western Arms

Post by jay851

so....do you think i should delete the pictures,as i dont want to cause more waves than we have already

jay
_________________
currently own:
hudson m3a1 greasegun
mgc early type open barrel thompson smg
kokusai s&w military/police 4" bull barrel

Post by Mark




NO!!!!! Jay, what claymore and i am saying is just for your your caution on this project. Just a "what if" nothing else! Waves? What Waves? Everything looks great to me!
_________________
Wanted to buy: MGC Sten MK3....trades?(still)

MGC MP40 Marushin MP40 Nakata MP40 TRC MP40

Modelgun manufacturers, past and present:CMC,CAW,Hudson,HWS,LS,MGC(R.I.P. 1960's~2007) Marushin,Marui,Kokusai,Shoei,Tanaka and Western Arms

Post by jay851


well..we have enough things going on over here in the u.k as far as the vcr bill,and i dont want to cause any friction towards the forum.

jay
_________________
currently own:
hudson m3a1 greasegun
mgc early type open barrel thompson smg
kokusai s&w military/police 4" bull barrel