The Spare Parts Bag
When we talk about being prepared and ready, we always think guns, ammo, shelter, food, and water. What we most often overlook is keeping our guns up and running while we get through whatever emergency/disaster we are in. I will refer to this as “the event”. This means having some spare parts for our ARs in the event we have a catastrophic failure. So, let’s talk about some of the most common parts that break and/or wear out, that you should keep on hand for an AR platform.
Number 1. Magazines. I know this kind of goes without saying, but it needs to be said. Magazines are expendable. If you listened to the Patrol Rifle podcast, you know this. If all you have are 7 magazines and that is part of your blow out plan, then you just have 7 magazines. Mags wear out, break, and get bent. There is not a magic timeline for mags. I have mags that are 8 years old that I use every time I’m on the range. I’ve also had mags that didn’t make it 2 weeks. We recommend you have some extra backup mags to replace the ones you have loaded or are planning to use for “the event”. Do not get attached to your mags. Do buy quality mags, though. Your firearm is only as good as its source of feed. If you buy cheap mags that will break or fail to feed, you have a nice single shot firearm. Good Pmags will cost you $20.00 or less.
Number 2. Bolt or Bolt Carrier Group (BCG). In my experience, the bolt is the second most common part to break. Usually one of the locking lugs, almost always the one to the right of the extractor, will break off. Your AR will still fire with a missing locking lug, but you do need to replace the bolt as soon as possible and only use that rifle for emergencies until the bolt is replaced. Continued use with the broken bolt can lead to a greater catastrophic failure, that could leave you missing some fingers or loss of life. Once the bolt breaks, it is more susceptible to another breakage. I put bolt or BCG for a reason. It is a lot faster to just replace the BCG then it is to pull the old BCG out and replace just the bolt. I have not seen a bolt carrier break, but that doesn’t mean it hasn’t happened. With the world events being what they are now (March 2021), parts are getting hard to find, so finding a bolt might be easier then finding an entire BCG. A bolt with a billet extractor is around $40.00. An entire BCG is around $120.00.
Number 3. Gas rings. Have an extra set or two of gas rings. These are so easy to replace and cost next to nothing. Even right now, they are less than $2.00 for a three pack. This is also one of the simplest things for you to replace and check. To check the gas rings, remove the BCG from the rifle. Start by pulling the bolt out to the out-of-battery position and stand the bolt-carrier group up on the bolt face. If the bolt collapses into the carrier, replace the gas rings.
Number 4. Gas key. This is that little hook looking thing with the hole in it on top of the BCG. The gas key is the part on the bolt that catches the spent gases and cycles the firearm. These can become loose if not staked, or just wear out. You can replace these yourself, and I recommend staking the newly installed gas key has well. Gas keys will run you around $8.00.
Number 5. Extractor. If you have a spare bolt, you should have a spare extractor too. This way, you are not wasting an entire spare bolt just to fix a broke extractor. Plus, a good billet extractor cost around $7.00.
Number 6. Firing pin. This is the part that slams into the primer and makes the gun go boom. Firing pins usually do not just break. Most of the issues with firing pins is wear. They become shorter from shooting, which will cause them to not make contact with the primer. This is an easy fix, and you will probably never need, but it is better to have and not need then to need and not have. A good firing pin will cost you less then $5.00.
Number 7. Springs. There are a lot of springs in the AR platform. The ones you are worried about are in the bolt and trigger housing. I recommend you just get a lower parts kit and leave it in the factory packaging. This way you have an entire parts kit to build a lower, plus a spare trigger. Again, you want to get a quality kit or springs. I like the mil spec springs because they work. Some of the competition springs are nice, but they can wear out faster and might not be as tough as mil spec springs. Brownell’s has replacement spring kits, as do some other manufacturers. A lower parts kit with a trigger costs $40.00 - $120.00, depending on who makes it.
Number 8. Barrel. Having an extra barrel in nice to have. Barrels chambered in 5.56 will typically last around 10,000 rounds. This is just an estimate. Some last far less and some last more. There are a lot of variables when it comes to how long a barrel lasts, so having one on hand is best, since we are prepared for “the event”. Which means when you need a new barrel, you will not be able to just order one off the internet or run down to Bob’s Gun Shop and get one. Barrels cost from $90.00 - $250.00 depending on manufacturer.
Number 9. Gas tube and gas block. Gas tubes do get “burnt” out and will need replacing. I recommend changing your gas tube and gas block with your barrel. These are the second part the hat gasses hit, so the ports will start to enlarge. A gas tube cost less than $15.00 and a gas block is less than $20.00.
The barrel, gas tube, and gas block are at the bottom of my list. This is because these have the least number of breakages that I have seen. But they are on the list because when you do need them, you might not have the ability to order them or get them. I also recommend you have a parts kit for each AR you have. As we say in the military, two is one. One is none.
You also need to have the proper tools in your spare parts kit/repair kit. It does not good having a spare barrel if you don’t have the proper barrel nut needed to replace it, or the punches need to remove the gas block. I like to go from front back on my AR and place each type of tool needed in my repair bag/kit. This includes hex wrenches, screw drivers, barrel nuts, and so on. And make sure you put whatever tools you use from your kit/bag back when you are done. You don’t want to be grabbing your go bags for “the event” and forget you never put that hex wrench back…..
—Chris #2