How often to replace lower parts?

[Pandaz3]

I am with most, if you are worried because you are unsure of previous use, I would replace the springs, If the safety detent still has good resistance, it probably has not been used much. One indication the lower likely has a lower round count, but you never really know do you. On the anti-rotation pins, I think they lower wear.

[M-Forgery]

For hard use I use 5,000 rounds for all operating springs, service the bolt, replace gas rings, replace extractor, replace gas tube, and at 20,000 rounds replace barrel and bolt.

For light aka civilian use you can go to failure, replacing the barrel at 50,000 rounds.

[Para554]

Unless you think that they’re worn out or it just makes you feel better there’s no need to replace anything in the lower. None of it wears enough to worry about, and you will most likely wear out a few barrels before you’ll wear out the parts in the lower. I have several ARs that have tens of thousands of rounds through them and nothing has been replaced.

[Iraqgunz]

You're incorrect, but that wouldn't be the first time someone posted bad information.

Unless you think that they’re worn out or it just makes you feel better there’s no need to replace anything in the lower. None of it wears enough to worry about, and you will most likely wear out a few barrels before you’ll wear out the parts in the lower. I have several ARs that have tens of thousands of rounds through them and nothing has been replaced.

[Para554]

You're incorrect, but that wouldn't be the first time someone posted bad information.

Okay, sure, but what would I know about ARs besides spending most of my career as a Special Forces operator, 18B, Weapons Specialist, the last 15 years as a gunsmith fixing things that break or fail for other reasons....

Besides that I don’t know anything at all about ARs. 🙄

[gaijin]

“You get one chance to make a first impression “.

[Iraqgunz]

I have 30 years of experience with AR family of weapons. In addition to that, I have been to dozens of factory armorer schools and worked overseas on weapons. I teach classes all over the country and see LE guns with worn out hammer/trigger springs. The same goes with buffer springs which can and do wear out. I have had officers flat out tell me that they had light primer strikes that they blamed on the ammo because they didn't know that hammer springs wear. I have pulled broken hammer springs from officers weapons as well as fixing ones which were installed correctly.

So the assertion that there is no need to replace stuff is flat out wrong. Additionally things like the safety selector detent also wear out and need to be replaced.

Okay, sure, but what would I know about ARs besides spending most of my career as a Special Forces operator, 18B, Weapons Specialist, the last 15 years as a gunsmith fixing things that break or fail for other reasons....

Besides that I don’t know anything at all about ARs. ��

[Para554]

I have 30 years of experience with AR family of weapons. In addition to that, I have been to dozens of factory armorer schools and worked overseas on weapons. I teach classes all over the country and see LE guns with worn out hammer/trigger springs. The same goes with buffer springs which can and do wear out. I have had officers flat out tell me that they had light primer strikes that they blamed on the ammo because they didn't know that hammer springs wear. I have pulled broken hammer springs from officers weapons as well as fixing ones which were installed correctly.

So the assertion that there is no need to replace stuff is flat out wrong. Additionally things like the safety selector detent also wear out and need to be replaced.

I think that by and large we’re arguing about the same thing, I simply did a poor job of stating my original point. Springs do wear out, some quicker than others. I was referring mostly to the other parts such as the hammer, trigger and disconnector for the most part. And I did say in reference to parts that need replacing “if you think that they’re worn out.” I would think that anyone that suspects that a part is worn out would replace it. However your point about officers not understanding that a light hammer strike could be caused by a weak hammer spring is point on, it would definitely need replacing. But if everything is running fine, unless the end user just wants something different I see no need to replace anything.

[Core781]

Whenever you buy a used gun, you should do a detail strip and inspect parts. Springs can be tested also for tension. Any part could be damaged or worn.. I always check chamber and bore. Don't replace any parts unless they're worn unevenly or damaged. Action spring can be replaced every 5-6000 rounds. Or get a CroSil spring and it will last as long as the lower.

[artoter]

If it ain’t broke don’t fix it. With that being said, you should always have spare parts on hand.

What he said.