MP40 How to Guides

Oooh. AK Hop for sure, please.

Also, I made a start on my MP40 yesterday (based on your previous thread), and found the Ver3 silent head was loose on the end of the original piston, AND, even if it wasn't, the AOE looks off (piston too long) with both silent heads, and borderline with just the silent cylinder head, but original piston head. So a bit more detail in that area would help, too.

Ok when parts get here I'll do an AK hop guide and an explanation of AoE.

Any more?

If there is a way to make the stock a little less wobbly ( I know the real ones were but it's still a pain) a how to on soring that would be awesome!

Working on a stock wobble fix ATM. Just need to finish the metal work first then I can start assembly.

AK Hop mod in bound. Just uploading to PB now!

we really need a popcorn smiley.

AK hop mod for MP40

Quick note.
This is how I do the AK hop mod and this is a guide to show you how it's done. Please read the whole guide before picking up a single tool or buying parts. If you don't feel confident doing the mod then by all means contact me or another gunsmith and ask them for help. All mods are done at your own risk.

For this you'l need

Simple hand tools

Phillips No2 screwdriver
Flat file
Small round file
Fine sand paper
Junior hacksaw[/list:u:mslo8qta]

Parts

TM compatible AK hop unit
AEG hop Rubber
247mm inner barrel
H-nub (optional but good)[/list:u:mslo8qta]



My personal choice of parts for this build

Element AK hop unit - Ebairsoft
Element H-nub - Ebairsoft
Vanaras 6.04 247mm barrel - RSOV
Guarder clear hop rubber - RSOV

Here is the standard AK hop unit. As it stands it will not fit and needs to be modified.



Start by cutting the feed tube at the point it necks down. Use a junior hacksaw or similar for this.



Now that narrow part of the hop unit was there for a reason as the main feed tube is too wide to fit in the opening of the magazine. You need to narrow the outside of the tube with a file to make it fit and feed correctly. Work SLOWLY and carefully! Most metal files are quite course and will make short work of soft plastic. Try and take and even amount off all the way round. You only want to take off enough so the it fits in the mag snugly. Make sure to file a bit then test fit it into your mag, keep doing this till you happy with the fit. If you want you can smooth the part you've worked with some sand paper of fine wire wool.

Here's one I did earlier...



Next you'll need to chamfer one side of the tube to allow the mag feed catch to be pushed to one side. A rough 45' angle works well. Again file and test fit till your happy. It should push the catch back without snagging.





Sorry for the image quality.

Right now the hard bit's done you need to start assembling you hop unit. Pop the sleeve onto the barrel and slide it into the hop unit. Make sure it's all straight and fit the barrel clip. Then put your nub in and fit the hop arm and pivot pin



Ok now you need to take a few bits from the old hop and barrel. They are the hop adjuster/slider and the two barrel spacers



Fit the hop adjuster as you would the normal AK one. Then slide the wider of the two barrel spacers onto the barrel. The ones I've done have been a tight fit and needed a bit of widening out with a round file. As always file a bit at a time, a snug fit is key to a good result!
Lastly push the muzzle end spacer onto the end of your new barrel. The muzzle spacer is a bit of a git to remove from the old barrel and my need a little help from some grips. If you break it just wrap tape around the barrel to the required thickness.



Now finally comes fitting your new unit in the gun. The unit is not screwed in like the old one. It is in fact held in place by the wide barrel spacer and the mag well liner. Your new hop unit should sight nice and tight in the hole in your liner. If it's too tight you can widen the hole or reduce the diameter of your feed tube. If it's a little loose don't worry as the mag will lock it in tight when inserted. Ideally you should test fit when filing the tube down in the first place.



Pop your gun back together and your done! Go out, dial in the hop and marvel at your handy work!

If you'd like to repost this guide or pass it on please do so but I'd like it if you credited me for it

Hope this helps

Thanks

Dave



 

which nub did you use? white or black?

cheers
Rob

Thanks, Dave.

Might be worth splitting this, and the future guides into their own threads to keep things "tidy", maybe referenced from this one.

WRT barrel length: 247mm? Where did I get the impression they're 229mm?

Yeah could be a good idea. Common myth is that they have an mp5 inner barrel. In my first build I used a barrel that fitted and assumed that it was an mp5 one. Turns out that the mp40 has a 255mm inner barrel and the closest to that is the G36 @247mm.

As for splitting and what not if the mods wanna do that then cool.

Regards

Dave

WRT barrel length: 247mm? Where did I get the impression they're 229mm?

viewtopic.php?f=13&t=11718&start=15

probably here, I bought the 229mm vanaras, will this still be ok??

Like I said I ASSumed Sorry

229 is fine chap

You missed this one, Dave:

which nub did you use? white or black?

😳

Like I said I ASSumed Sorry

229 is fine chap

cheers, just need to order an element AK hop now

I got a 229, too, but I have a TM MP5 I can use it on.

I use the white one personally. But if you have a newer pack of element H nubs they're both the same dimensions.

cheers

Nice one on the hop upgrade, ordered the parts today from RSOV.
If possible can you do a guide on the following upgrades to the gearbox and a parts list;
re shim, metal bushings, new piston head, spring guide & spring, tappet plate and an alternative trigger switch as opposed to mosfet.
Thanks
Best Regards
'shokt

Trigger mod is on the cards as of tomorrow. Guide will be up by monday.

Here's an example of parts to use.

Spring-http://www.rsov.com/product.php?langId=1&currencyId=4&manufacturerId=10&prodId=4252&cateId=142
Spring guide-http://www.rsov.com/product.php?langId=1&currencyId=4&manufacturerId=10&prodId=4033&cateId=142
Piston and head- http://www.rsov.com/product.php?langId=1&currencyId=4&manufacturerId=10&prodId=14120&cateId=194
Bushings-http://www.rsov.com/product.php?langId=1&currencyId=4&manufacturerId=10&prodId=14333&cateId=142
Shims-http://www.rsov.com/product.php?langId=1&currencyId=4&manufacturerId=10&prodId=5047&cateId=142
And IF needed
Tappet plate-http://www.rsov.com/product.php?langId=1&currencyId=4&manufacturerId=10&prodId=1531&cateId=142

A good guide to shimming and bushings (a V2 box is used but idea's identical) http://www.mechbox.com/mechbox/v2-mechbox-spring-upgrade.html

Hows that

That is most excellent my talented friend!
Thank you very much
Regards
'shokt