For the purpose of this stickie the Yugo MG53 can be considered identical to the German MG42. Also please consider .308 and 7.62 X 51MM identical.
While I acknowledge there are differences in both examples those differences aren't important to the purpose of this stickie.
Most parts , like bolts, flashhiders,buffers & recuperators are interchangeable between calibers.
Step 1
Identify these parts of your kit or gun that are on this list & determine their caliber.
- 1) Barrel ............. part #72 ............ 8MM or .308 only
2) Topcover ......... part #34 or #79 ... 8MM or .308 only
3) Feedtray ......... part #80 ............ 4 different variants
4) recoil nozzle ..... part #84 ............ Many different variants
link to detail parts break-down.
Step 2
Determine what model you have based on barrel , topcover & feedtray combination.
Correctly identifying the feedtray should identify the model variant
- MG 42 = pure 8MM
MG 1 = hybrid .308/8MM
MG 2 = pure .308 patterned after 8MM
MG 3 = pure .308
Step 3
Determine what model you want to achieve .
Do you want to run 8MM only?
you want an MG 42 set-up.
Do you want to run both .308 & 8MM as cheap and with as few parts as possible?
you want an MG 1 = A hybrid 8MM topcover & feedtray converted to .308 set up.
Do you want to run .308 on belts only?
you want an MG 2 set-up.
Do you want to run .308 on M60 links or belts?
you want an MG 3.
Link to brief history of the models.
Step 4
Use this guide to determine what parts you need to change to achieve your conversion goal.
------------------------------------------------------------------------------------------------------
Barrels
While it seems obvious we need to state,
A 8MM barrel should only be used with 8MM ammunition.
A 7.62 X 51MM barrel should only be used with 7.62 X 51MM or .308 winchester ammunition.
------------------------------------------------------------------------------------------------------
Top covers & feed trays
A 8MM top cover will work with
1) an original MG42 8MM feed tray
2) a MG42 8MM feed tray converted to an MG1 .308 feed tray.
.....NOT a MG2 or MG3 .308 feed tray. [/size]
A .308 top cover will work with either
1) A MG2 feed tray using DM1 belts only.
2) A MG3 feed tray using DM13 links or DM1 belts (if you don't mind the extra wear on your belts).
.....NOT a MG42 - 8MM feed tray or MG1 .308 feed tray that was originally manufactured as 8MM.[/size]
------------------------------------------------------------------------------------------------------
Recoil nozzles
Sadly there is no definitive answer to give on recoil nozzles , they have been proving to be a trial and error situation to achieve a balance between cycling the action reliably and excessive recoil .
Try to use the largest nozzle opening you can with the ammunition your firing and still achieve reliable cycling. 8MM guns will need and should come with a larger opening than the .308 guns .
link to recoil nozzle thread.