My strong advice is, if you are asking these types of questions, you don't know what you are doing so take it to a gunsmith who knows what he is doing to do it.

Just my HO.

I don't know about Heym's but I do know you only get one chance at stoninga trigger and once metal comes off, it is damn hard to put it back on.

And the difference between a smooth trigger and a trigger that fires itself off (ie the double rifle will double on firing the first barrel) can be quite small.

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