Question about ejector springs

Left Sig · #1 01-21-10, 22:00

One of my M4 style AR's occasionally gets stovepipe jams. I thought the bolt was closing too fast or the extractor was letting go too soon, so I've upgraded to a black spring insert, and just added a heavy buffer.

But I noticed something odd when I tried to upgrade to the heavy extractor springs from Tactical Springs. The extractor grips the case so tightly, that the ejector can't pop it out when I pull back on the charging handle to open the bolt! Maybe it would eject when firing, but I haven't tried it yet.

I have another carbine, and with the same extractor spring, the case will eject when the bolt is opened.

So, do I have a weak ejector or bad ejector pin on the one that "sticks"? Or might it be something more problematic like a bad bolt head recess...

6933 · #2 01-21-10, 22:12

Try a BCM extractor upgrade kit. Can't hurt, good product, and cheap. May be the easiest fix, or quickest way to rule out these as probs.

notorious_ar15 · #3 01-21-10, 23:26

I've had good luck with the David Tubb / Superior Shooting Systems ejector and extractor replacement springs.

Quib · #4 01-22-10, 07:09

You could have a weak ejector spring, it’s a possibility. Another possibility is firing residue or brass shavings that have migrated into the ejector pocket of the bolt.

A quick check would be to take a pin punch or similar object, and try to depress the ejector. You’re looking for smoothness of travel and a positive return. Should the ejector stick at any point or feel rough, you might want to disassemble, clean, inspect, lube, then reassemble the ejector assembly.

I think one often times over looked lube point on the AR, is the ejector and spring. The -10 Operators Manual calls for placing one drop of lube on the ejector, and working the ejector in and out to allow the lube to work its way into the ejector pocket.

Norcal911 · #5 01-22-10, 13:37

I've run AR's in various forms for quite a few years, work, play, 3 gun etc. Through all of that experience, I never payed much attention to ejectors, had never taken one apart, etc. Fast forward to a few months ago and I started noticing that my brass was landing at my feet and I was occasionally having FTEs with a previously 100% LMT MRP. I did a hasty cleaning, same problem. Fortunately somebody smarter than me pulled my bolt, showed me how to disassemble the ejector and clean it up. I was horrified at how many brass shavings were in the tube and spring. Blasted it out with carb cleaner, reassembles with a heavy dose of oil and I was back in business. Learn something new everyday. Look at where your brass is landing, if its landing at your feet, you may have an ejector problem, worn/dirty, etc-Norcal911

handyandy · #6 01-22-10, 15:44

Take a round, spent or live, hold the assembled bolt in your hand, hook the round on the extractor and rock the round over, depressing the ejector. It should have stiff resistance and not bind up in its travel. I always put a drop of oil on the bolt face and do this when I am done cleaning an AR. It works the oil into the ejector. It's not a bad idea to take the ejector apart every 5,000 rounds or so to clean it, but most people never do and don't have problems.

Iraqgunz · #7 01-23-10, 19:06

Personally I would replace the ejector spring if I had any doubts about it. Also, it is possible to have too much extractor tension. A standard upgrade kit using an M4 spring and insert is usually enough.

I use a punch and push in on my ejector. If it feels weak, I replace it.

Robb Jensen · #8 01-23-10, 19:47

If your extractor spring is overpowering your ejector spring you should inspect and or R/R your ejector spring and ejector. If it still overpowers it you have way too much extractor tension either remove the o-ring or use a standard extractor spring w/black buffer and the o-ring.

HD1911 · #9 01-26-10, 20:31

Quote:

Originally Posted by gotm4

If your extractor spring is overpowering your ejector spring you should inspect and or R/R your ejector spring and ejector. If it still overpowers it you have way too much extractor tension either remove the o-ring or use a standard extractor spring w/black buffer and the o-ring.

I feel like such a tool for asking...but where is the ejector spring and what does it do? I have upgraded my extractor with the BCM kit...and have stripped my M4 down for cleaning several times...

Dos Cylindros · #10 01-26-10, 22:20

Quote:

Originally Posted by HD1911

I feel like such a tool for asking...but where is the ejector spring and what does it do? I have upgraded my extractor with the BCM kit...and have stripped my M4 down for cleaning several times...

The ejector spring is located inside of the bolt assembly. If you look at the bolt face oposite of the extractor you will see a cylindrical object protruding from the bolt face. That is the ejector, the spring is located behind it and all is held in with a roll pin that is located going from the top to the bottom of the bolt just behind the locking lugs othe the opposite side of the extractor. Sorry, no pic.

Quib · #11 01-26-10, 22:52

Quote:

Originally Posted by HD1911

I feel like such a tool for asking...but where is the ejector spring and what does it do? I have upgraded my extractor with the BCM kit...and have stripped my M4 down for cleaning several times...

http://generalcartridge.net/Document...005-319-23.pdf

HD1911 · #12 01-27-10, 10:19

Quib and Dos Cylindros....thank you very much.

How often, would you say, should I replace the Ejector and/or Spring?

If I've upgraded to the BCM kit...is that too strong for the stock ejector/spring?

just trying to understand it all, thanks again!