Disassembly/Reassembly Don'ts

[Doc Safari]

I was re-reading some of the cleaning stickies and others, and I also did a search for do's and don'ts...but I've never found a concise checklist of things you should avoid while cleaning and disassembling (or reassembling) that can damage the rifle or its parts.

For example, all of the manuals say not to "open or close the split end of the firing pin retaining pin", yet is it okay to pinch the ends together slightly to help it into the hole in the bolt carrier? I tend to try to rotate mine slightly to get it in, but someone asked me this question the other day and I didn't have an answer.

To remove the buffer, you depress the buffer retainer pin and most places say to then release the buffer. Will it damage the buffer if in so doing it hits the hammer? I've had this happen in years past on occasion no matter how careful I thought I was being.

A lot of places I've read seem to indicate you never let the hammer go with the receivers separated, yet I have seen people do this. I watched one guy do it repeatedly, I guess to test the spring tension, on a used rifle he was thinking of buying.

One reason I used to get frustrated when I owned my AR's years ago is that I just couldn't figure out how to clean that long skinny gas tube, and then I found out years later that you don't clean the inside of it. :jester:

I was also one of those guys, like many others, that religiously made sure the gaps in the bolt rings were staggered before I knew better.

One of my favorite "myths busted" is to use the firing pin to disassemble anything. I understand that can eventually blunt the tip or otherwise damage it.

I'm just wondering if there is a thread I can't find somewhere, or if maybe we could start one, on all these little subtle things the manuals don't tell you? :D

[Tweak]

Don't close the upper onto the lower when the selector is on AUTO.

[120mm]

For example, all of the manuals say not to "open or close the split end of the firing pin retaining pin", yet is it okay to pinch the ends together slightly to help it into the hole in the bolt carrier? I tend to try to rotate mine slightly to get it in, but someone asked me this question the other day and I didn't have an answer.

The firing pin retaining pin uses tension to stay in the hole. Opening or closing the gap is like stretching a spring; it weakens the metal. The amount you compress it to insert it in the hole isn't enough to permanently "work" the pin past its critical point.


To remove the buffer, you depress the buffer retainer pin and most places say to then release the buffer. Will it damage the buffer if in so doing it hits the hammer? I've had this happen in years past on occasion no matter how careful I thought I was being.

Will hitting an anvil with a hammer hurt either? These are two very robust parts that are hard to damage.


A lot of places I've read seem to indicate you never let the hammer go with the receivers separated, yet I have seen people do this. I watched one guy do it repeatedly, I guess to test the spring tension, on a used rifle he was thinking of buying.

Both the guy who did this repeatedly and the guy at the counter who allowed it, need to be slapped. If you want to test the trigger, do it with both halves put together or put your hand in front of the hammer. The relatively fragile lower receiver is not designed to be hammered on.

[Redhat]

Do install the firing pin correctly...Don't install the firing pin "after" installing the retaining pin or without the firing pin inserted fully into the bolt carrier..

[Iraqgunz]

I'll bet most people would be just fine if they actually got an operators manual and just read through it.

Couple this with the application of common sense and suddenly the improbable becomes possible.

[fixit69]

thanks doc,

Cleaning? Its a silpery slope. Thanks for the input. Cleaning is a regimen. So, that is a VERY personal thing. No dog in this fight. Clean the ****ing GUN.

Weapon, rifle, pistiol, MG, doesn't make a difference. CLEAN it every once in a while. And do it well, if you bother to.

ETA: Thanks to 120mm too. Same to you. IG, couldn't said it better

[Doc Safari]

I remembered another one this morning.

I have learned you do not use a 5.56/.223 cartridge for any kind of disassembly that might involve some effort. Using the tip of the bullet to start the firing pin retaining pin out of the hole seems to be okay, but in my young and stupid days I ruined a several rounds by using the cartridge to disassemble magazines. I learned that's a good way to bend the bullet out of the case so the round is unusable.

I can't remember if I read in a manual that you could use the cartridge as a tool, or if it came from all us guys using 7.62x39 cartridges to work the gas tube latch on the SKS, but what works on Soviet weapons ain't too good for your ammo with the AR. I seem to remember seeing diagrams of soldiers using the bullet tip to adjust the M16A1 sights.

(Personally I don't even allow ammo anywhere near the bench while cleaning anymore. That's just my personal safety rule).

[Doc Safari]

Here's an interesting discussion on a forum I accidentally ran across.

The discussion, featuring our very own Iraqgunz, includes some ideas about whether improper disassembly/reassembly might cause receiver holes to egg out.

http://www.professionalsoldiers.com/forums/showthread.php?t=29900

[devinsdad]

The military taught to use the firing pin to remove the extractor pin and to use a round to depress the detent to change the sights. Now that I have punches and tools to do these things, I dont use the militarys methods, but they are good to know in case you are without.

[Doc Safari]

While on the subject of egged out receiver holes, I found another discussion right here:

http://creativepromotionalmarketing.com/showthread.php?t=62977

I think people worry about pin rotation wearing the holes because they do not truly understand how anodizing makes the aluminum receiver resist wear from steel axis pins.

I'm with Iraqgunz in believing that improper disassembly is the cause of most egged out receiver holes.

(Of course we're discussing properly manufactured lowers and not some low tier example that might have been painted instead of anodized).