If i built it and proofed it i would, and it would not blow up any more then any other gun with reloaded ammunition.
And i didnt mean it would give away as blowing up i ment give away as in off face/dented breech. And this would not come at once, it would show up long before it would be harmfull to fire it. I have seen merkels blow up right at the end of the chamber and they didnt open a tiny bit, thats a bit more pressure then the 40000psi a 470 generates.

Also im not saying he should build it, im saying i would give it a try if i got the parts.