My previous boat, a Jeanneau 37, had 10mm chain. When we bought our Santorin (twice the weight) it had 8 MM. chain. I asked the surveyor about its suitability. He checked some tables which indicated that 10mm was more appropriate.
We changed to 100m of 10mm in Sardinia with a new gypsy. There is a Rocna 25 on the end of it.
I am happier with the 10mm because of the catenary effect of the chain's weight relative to the 15 tons of the boat. There is less jerk on the whole system. We prefer to anchor and have done so from the Med to Scotland and the Caribbean, 3 times in F9. The boat has always felt comfortable.
I'm sure there would have been no problem with 8mm. I just feel some reassurance in weight of chain x length of scope etc.
No issues with weight in the bow - I'm sure you've already noticed the stern down aspect of Amels!
The only issue this year was the tendency of the chain to pile up and jam in the hawser hole with 8 metres to stow!! This was because I reversed the chain and the still new end had quite a bit of salt on it. It's now worn in and runs smoothly.
My advice would be to suck it and see. The boat had obviously managed well with 8mm so far. Put that one lower down the wish list.
Ian 'Ocean Hobo' SN96
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