I’m researching the parts that would compromise a realistic spare part kit for an AR-15. So many small parts, easily lost and a few will break. I don’t want to depend on items being available in the future to keep my rifle working.
Give me a description of your kits and suggest available ready made parts kits from vendors. Thanks in advance!

I would check with Brownells, Midway USA, and Sportsman's Guide. I know the last two sell them for sure. I can't see why Brownell's wouldn't have them as well.

I have never had a part fail.
But it would be a good Idea to have a couple of extra extractor springs in case you disassemble the bolt farther than you should for cleaning and lose the spring.

A parts kit for the bolt would be a good bet. Or just a spare bolt. I had trouble with the cotter pin that retains the firing pin being very hard to get in. I tried persuading it with a very small brass ended jewelers mallet and it broke. Just so happened to make it to the gun show were I bought some parts and the guy gave me one free of charge.

The most common parts I have seen fail or just plain wear out are the bolt parts. You can put your own spare parts together or companies like Rock River Arms have bolt rebuild kits already assembled.
Upper Receiver Parts (Part#AR3258)
In addition as Model 5 already mentioned, keep several of the firing pin retaining pins, they are easily lost during cleaning and once the legs start to spread apart they become difficult to reinsert. They are cheap.

Depending on the trigger that your rifle has, you may want to have spare, hammer, trigger and disconnector springs. There is not much else that you need. Most everything else would involve a major failure. I am working on putting together an entire complete bolt & bolt carrier for each of my AR's (13) that include several different calibers.

Thanks all. Found everything at Brownells. Think I’ll go for a bolt carrier group and a set of springs to start.

What is it about the AR-15 that owners suddenly feel they need to keep spare parts? Do you keep spare parts for your other rifles and handguns?

Springs and retainers have a habit of disappearing when cleaning& lubricating my AR's or flying off to hidden places.
I am waiting right now for 3 different sets I ordered 3 days ago from Midway
I have learned to back ups for my back ups. I also have all my original triggers from my other rifles in case the upgraded one craps out.
I learned from running a sport fishing boat from Fla. to Ny. that
there is no service station 30 miles off the east coast & it takes along time for the Coast Guard show up.

Because they can be had easily and cheaply, are easy to change out without tools, are known wear and tear parts, and they don't take that much room or weight that much.

Unless you start talking about carrying an entire BCG with you of course.

I have a oops kit with extra O rings ,springs and pins for my AR . Wolff spring kit for my 5906 so far all had to replace was mag release spring and extra RSA for my M&P pistol

Buy a second AR. If (big IF) something breaks you'll still be in business and you will then know what to buy. My version of a New York reload.

__________________
Foster Positivity.

I do keep spare parts kits for the guns I shoot a lot. Remember that access to a gunsmith in the future is not guaranteed.

Actually I do have spares for my other military type rifles and spare springs for all my handguns. A couple of Wolfe spring kits covers all my Smiths. Not to mention magazines. As I posted, I don’t want to take the chance that these parts and magazines will always be easily available.

Spare bolt, mag release, bolt release, charging handle. Selector switch detent and spring. Bolt cam pin, Spare trigger and hammer springs. Buffer tube springs. Heck just about everything except the upper and lower receivers, lol.

I just found an excellent video on Brownells website on the subject. Well worth a watch.

That had to be an Aero BCG


I had the same trouble with the firing pin retention pin and I saw some other guys who did too. I got another one for I think 50 cents and it's fine.

I always find it touching-and troubling-that so many people think the bolt and/or BCG is plug and play. While the replacement probably will pass a FIELD gauge (point at which the rifle is no longer safe to operate), it's unknown if your new parts would pass either the GO or NO-GO gauge. The second gauge tells you that even after the bolt wears in that headspace will remain acceptable. FWIW, the bolt carrier is pretty much a life of the rifle part.

Moving on, I'd suggest at least one set of spare gas rings, instead of the firing pin retaining cotter pin, the solid retaining pin of the original design is available. I'd also suggest that one of the little fixtures that allows you to capture the ejector while taking the bolt apart is money well spent. A spare cam pin isn't a bad idea either. Don't forget the little black plug that goes in the extractor spring. BTW, if you have a choice, the M4 extractor spring is heavier-although by now it may have completely replaced the rifle spring.

Funny, I always find it touching and troubling when some rando decides to be condescending in my general direction. I was a Police armorer for 25 years. When I use a part, it will fit.