Clean old beer bottles.

[531Man]

Are you sure Oxyclean will render something sterile? And if the bottles aren't clean, they won't be sterilised anyway.

I get what you mean, but even soil (dirt) can be sterilised.
After all the OP's detergent, physical cleaning and oxycleaning, without having seen it, I would expect the uncleanness left is just a stain left on the glass. Oxyclean and its like are approx. 30% available Oxygen in the form of Hydrogen Peroxide.
Strong enough to sterilise that stain, provided that is all there is present.
As I say, it seems to have worked on my much older and sometimes initially internally cruddy bottles (that is before the cleaning sequence! ) that have been described as old rubbish tip recovered.
I suppose belt and braces would be a further rinse with Starsan/Chemsan acid type of sanitisers, but I haven't found it necessary - yet. Touch wood, famous last words etc.
I can't use boiling water/dishwasher either as it would thermal shock shatter that old bottle glass. Accidentally found that out to my cost with one beautifully embossed Victorian Isle of Wight bottle.

 

[Binkei Huckaback]

I get what you mean, but even soil (dirt) can be sterilised.
After all the OP's detergent, physical cleaning and oxycleaning, without having seen it, I would expect the uncleanness left is just a stain left on the glass. Oxyclean and its like are approx. 30% available Oxygen in the form of Hydrogen Peroxide.
Strong enough to sterilise that stain, provided that is all there is present.
As I say, it seems to have worked on my much older and sometimes initially internally cruddy bottles (that is before the cleaning sequence! ) that have been described as old rubbish tip recovered.
I suppose belt and braces would be a further rinse with Starsan/Chemsan acid type of sanitisers, but I haven't found it necessary - yet. Touch wood,

Would you want that in your beer though? Even if 'sterilised' (which it can be only if permanently left in a sterile environment), it could still flake off and taint the beer. I wouldn't risk it.

 

[531Man]

Would you want that in your beer though? Even if 'sterilised' (which it can be only if permanently left in a sterile environment), it could still flake off and taint the beer. I wouldn't risk it.

In the long run, that's probably the safest approach.
Just as an experiment, to prevent drinkable beer being wasted, how about this?
Take a couple of the cleaned but still 'dirty' bottles and give a brief but thorough swill out with ordinary metabisulphite/Camden tablet solution.
Fill with a very weak sugar/malt extract mixture that has been boiled and cooled (glass bottles here, remember). Leaving a headspace of 5cm before putting on your closure (crown cork, clip-down top, screw-on cap whatever) to hold any pressure.
1/2 of a teaspoon per pint; 2.5g per 500ml should do.
Basically treat as if conditioning a bottle of beer.
Open bottle after a couple of weeks, pour and see if anything is living in there! Or any crud flaking off.
If so, don't use any of those gift bottles for your beer.
A secondary (or run in parallel) check would be to add a little active yeast with the (cooled) solution and see if there is any difference.
Any off smells or contaminating growth should be obvious, but I wouldn't recommend drinking any of it!
I thought about doing this myself now, but then realised I already have with my beers.
Good luck,
Robin.

 

[proost]

Thin chain or failing that even gravel shaken around in the bottle shifts nearly everything.

I didn't think of a chain, I'll try that