Shoei Mkb42 (H) Modelgun

Hi everyone I’m from New Zealand and it’s really difficult to get these Here And Luckily I was able to find this from GUNCITY NZ so ITS NO NEED FOR THE CUSTOMS CLEARANCE HASSLE. I’ve recently got this beauty delivered into my hands Shoei Mkb42 (H)  Dummy Cartridge Version
And It’s also comes with a pack of 10x Catridges. The ONLY THING I WISH THIS MODEL GUN SHOULD OF HAS IS THE ABILITY TO FIRE FULL AUTO

Hi Kororiaria,

Congrats on finding one in NZ. The MKb42(H) is a really interesting firearm which was the forefather as you'll know of the MP44 / StG44

When Shoei manufactured a limited run of these, 150 cap-firing models if memory serves me correctly, several years ago I bought one and still have it. Another forum member helped me get it firing properly with several modifications. It'll fire Semi and Full Auto reliably and consistently. 30 bursts are fully achievable.

It's a shame Shoei didn't make more of them with their last run.

Enjoy it 

Hi Cerwyn, Thank You. I’ll like to ask you how did he manage to get it to fire automatically for you, Is it difficult to modify? What parts did he use to modify

Cheers

There's a select fire switch on the MKb42, push through one way for Semi Auto, the opposite way for Full Auto. You can replicate semi / full auto by pulling the charging handle back'n'forth with trigger squeezed.

Bearing in mind it took 12 months with other jobs thrown in, it was a lot of work.

Bolt was remade in steel, new detonator pin in steel to replace Shoei's original. The bolt is picked up by a "hook" on the carrier which is zinc alloy. Auto firing would likely break the "hook" so the rear of the bolt was drilled and tapped then bolted to the carrier. This keeps the bolt lined up during firing too.

The original cartridges were too complex, too heavy and needed two caps, 1 x 7mm + 1 x 5mm. A new cartridge design was made from aluminium and brass. Only 1 x 7mm cap needed now. Imitation primer and internal piston are from my spares boxes, probably MGC.

So when you say bolt you talking about the extractor is that right. That’s now been replaced with steel instead of the zinc alloy.

And for the select switch are you talking about the two switches below the trigger guard near the handle. I thought those were the safely button but NO I was wrong I can still pull the trigger regardless of the buttons right.

And the original cartridges do they like not fit when you modified your gun like did you have to now use 1 x 7 mm caps.

Thank you I’m new to this and recently become my hobby

I was meaning the entire bolt, not just the extractor. All of it is now steel on mine. The bolt carrier, the longest part which includes the replica gas piston, is still the original zinc alloy.

The Safety mechanism is on the Charging Handle. Push it IN to lock the Bolt stopping it moving.

Select Fire push through switch is by the trigger group. To test it, pull the charging handle back to cock the gun. Squeeze the Trigger and keep it squeezed. The bolt will move forwards to strip a round from the mag' and fire it. Don't forget the MKb42 fires from Open Bolt, NOT Closed Bolt like the MP44 / StG44.

With trigger still squeezed, pull the charging handle back again. If it Cocks and doesn't move forwards again as if firing then it's in Semi, ie single shots. Let the trigger go, the gun will reset itself. Squeeze the trigger and then it'll allow the bolt to slam forwards again.

However, if you pull the charging handle back to cock, squeeze the trigger, don't release the trigger for this, allow the bolt to slam forwards, pull it back again. If the bolt doesn't stop at cocked position but will slide freely forwards all the way and do so repeatedly you're in Full Auto.
It'll continue to slide forwards until you release the trigger. Once the trigger's released the bolt will stop at cocked position.
You can do all that without a mag' or dummy rounds.

The original Shoei cartridges were complicated and heavy. Gas sealing inside the brass case when fired was so complete it made taking them apart difficult and hindered easy firing. The brass rims broke off regularly too. The home built aluminium cartridges were lighter, simpler and more efficient.

Have a look at the article I wrote at the time:  
https://mp40modelguns.forumotion.net/t4649-shoei-mkb42h-firing-version

With all due respect, if you're new to the Modelgun hobby and aren't experienced at machining, gun smithing, leave your very expensive Shoei replica as it is. You don't want to cause it any damage whatsoever. They're scarce, mega expensive museum quality replicas.