Advice needed from Marushin gunsmiths/tinkerers.

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Hi Brough!

I just found your post and must say I like your idea very much.
Anyway I have not done such modifications as I am not skilled enough. All I have done was adding a steel XM177 flashhider and it turned out great.

A friend with a mill was able to drill out the holes for the take-down pins and make replacement pins out of stainless steel so there was no more play between upper and lower receiver ...

If done carefully and properly, I am quite sure the lower receiver can be rethreaded. The zinc should be able to take it. Same with the barrel if you find a way to attach it properly.

I think it is worth the risk. If broken, spare receiver parts for Marushin can be found in Japan ...