www.MG42.us

I guess what I was concerned about was the fact that the rear of the recuperator would not be resting against anything. Wouldn't that put extra stress on the mounting bolts for the recuperator, perhaps even causing them to shear off?

Thats actually a great question.
The bottom of the recup rests against the buffer tab as well as the tube that holds the springs.
Wiselite must of found a way to support the 42 style recuperator so, if you have the clearance for the tail of the MG3 style recup the mounting should be the same.
Maybe wiselite or someone who has one can chime in.

A nice thread about taking the recuperator apart.

http://mg42.us/viewtopic.php?f=10&t=12733

Later 42rocker

Is it possible to use a MG3 recuperator in a MG42, and if so, what must be done and what parts are needed?

The MG3 recuperator is different and will not fit. It has a longer tail due to the fact it has an added spring giving it the extra length. The lower buffer tab on and MG3 rear has a cut out for this longer tail to support it. The MG42/53 has the support on the grip hanger for its shorter recup. The buffer on the MG3 has a relief cut as well.

That said you could modify the 42/53, but it would not be easy.

I used an MG3 recuperator on my MG3 semi clone build. I removed the M53 grip hanger recup support and used the MG3 rear section from RTG that has the MG3 tabs. When you are building it's not a big deal, just a matter of deciding what you want, but after the fact it would be a difficult modification.

IMO there isn't any big benifet in using one, the reason the post war Germans went to it was because the .308 round has a sharper recoil pulse. But the 8mm type works fine in .308, at least for our use.

Der Alder, thanks for the reply.
I was looking at the grip hanger, and I understand now how it supports the back of the 42/53 recuperator and how a MG3 grip hanger would be needed to use a MG3 recuperator. How is the grip hanger attached to the receiver? It looks like it is held in place by the lug that fits into the tripod, and the lug looks like it's held in place by a staked pin that runs up through the receiver and grip hanger. Am I wrong?

Here are a few related pics from when I built my semi MG3 clone.
First shows the MG3 recuperator compared to the 8mm type (8mm type in pic has its plunger removed), but the longer tail and added spring are the main difference. That and there is sort of a hump on the rear mounting area, along with a cut out of the flange near the ejection port area for added clearance for the fatter 7.62 case.


This pic shows the modification I made to the M53 grip hanger, cutting it's "tail" recup support off.


This pic shows the MG3 type rear section and how the lower buffer tab is cut out in order to support the longer MG3 type recuperator.


The grip support/hanger is riveted and has a bolt that goes through holding the rear of the recuperator. Here is a pic of mine after it being located prior to welding. The hole is for the recup bolt which goes through the grip support, bolt blocker and through the recuperator. I just welded the grip support in place, welding the rear, sides and plug welding the rivet holes (over top of the semi bolt blocker). Notice the square hole in the reciever is no longer needed in an MG3 build because the tail will not be used.


Hope this answers your questions.

Thanks Der Alder.
This helps greatly. I'll have to do some more research, but it does appear to be more difficult than it first appeared to convert a MG42 to use a MG3 recuperator.

This is a great description. I replaced my recuperator recently after many frustrating attempts to get it to fire correctly. The most common result was light primer strikes when I tried to fire. After installing an old M53 part from a spare parts kit, it worked just like designed.

This description provides great information.

Thanks

Bob

How hard is the recuperator supposed to be to be pushed in? I can only get the bolt to disengage the barrel extension if I take the flash hider off and manually push down on the barrel bushing while putting some weight on the charging handle with my foot. Or giving the gun a good smack downward. It seems it is the correct length, because the barrel goes in well, and the recuperator is touching the barrel so there is no play.

It is just too hard, I cannot pull on the charge handle hard enough to overcome the recuperator. Any suggestions or tests I can do to see if it is something else? I haven't shot it yet, still building. But close.


I was thinking of replacing the metal pin that is in between the recuperator "plunger", and the interior Springs with another spring that is weaker. Strong enough to where the barrel is still supported completely forward even with the gun sitting on the butt, straight up. But easy enough to where the charging handle can pull the bolt free.