What parts and from whom is a problem - there aren’t major flags or lists with 5 star guarantees. Even Colt had problems at one time. It’s usually never seen, but sometimes decision makers will trade off their Brand name and provide lesser quality parts for increased profits.
If it’s for a short period, it doesn’t seem to be anything more than “Oops, we shouldn’t have got those. Sorry!” And that happens, too. Suppliers can and have misrepresented the quality they vend.
Major parts are generally described as milspec with the method of testing to ensure they pass quality checks. Bolts that have been shot peened and magnetic particle inspected, for example.
Smaller parts aren’t often so described. At that point you fall back on the reputation of the source. Buying Colt lower receiver parts should deliver a higher level of reliability than shopping for the cheapest kit on the i-net. It takes a lot of forum surfing and introspection to get a feel for the middle of the road items.
One thing to sort out is whether the parts are used and recommended by those who actively shoot at a lot of matches. Of course, these same folks are often sponsored by makers who want to add their luster to the image. Marketing is often filled with a bit of puffery, let the buyer beware.
The end use of the rifle also plays into it. If the shooter doesn’t go out every weekend burning up a thousand rounds, or even a hundred, it may never be discovered whether a part could fail for a long time. Civilian retail quality standards do a good job for those who only shoot a few times a year - and those owners still tend to rave on about what a great piece of gear it it.
It boils down to - you do get what you pay for, but will the shooter use his rifle enough to exercise the difference? Plus, if vendor X wants $$$ for his part, where can I find it for less?
Approach the situation with the same skills used in hunting: Find where the quarry frequents by actual sightings, focus on productive areas, and be there when the quarry is.
Keeping tabs on a website like this one will increase the opportunity to discover what parts are the better ones, who sells them, when they may be on sale, or even purchased at discount used from someone who is burning up their cash experimenting to find out what they like.
There’s a simple answer, but not an easy one. Of course, if it was easy, then everyone would have a great AR and there would be no junk stuff on the market at all.
Hope that helps.
