Piston Ring End Gap

I'm going to be replacing my pistons along with new rings this weekend. (2004 TDI)

I understand the importance of checking the end-gap on the rings when building any non-standard engine, for example if it has been bored and the rings are oversize, it might be necessary to file the ends to adjust the gaps.

What about a standard bore with standard rings? Surely they would make them the correct size to just drop in, wouldn't they? Otherwise it would be disastrous for anyone who forgot to check.

https://www.ms-motorservice.com/fil...nbau-kolbenringsaetze_piston-ring-sets_en.pdf

These instructions from the manufacturer make no mention of checking or adjusting the end-gap specifically. Can I safely just use them as-is? Seems that way, but if anyone has more experience and knows otherwise, I'd like to know.

I had the head off a couple months ago, so I know my bores are in good shape. There was no ridge at the top at all. Cross-hatching is still visible. Engine only has 175,000 miles on it.

I've already put the rings on the pistons, and it would be better if I don't risk breaking them to take them off and check the gaps by putting them in the cylinders. The engine is not apart yet. These are replacement pistons.

I believe that's something you want to check whenever they're replaced for whatever reason. I bet you'll be OK.

I would check them if possible. You never know what you are getting. A few years back I was rebuilding a GM V8 Diesel. I bought all new +020 Mahle pistons and rings. I checked all the end gaps and discovered one of the compression rings was way out. I can only assume that somehow an incorrect ring was put in the box by mistake at the factory. 99% of the time all is fine, but unless you check, you don't know for sure. You will need a ring gap filer if you have to file the rings.