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prepare
05-22-21, 13:36
Is there a definitive way to measure ejector tension? Or do you just measure the ejector spring?
tehpwnag3
05-22-21, 22:46
Measuring the spring is a relative pita even with a jig to hold the ejector in place while you drive out the roll pin. I mean, it's not like pulling an action spring to measure free length.. The last time I had a carbine that was having intermittent ejection issues I pulled the bolt and hooked a cartridge rim on the extractor claw and levered it down flush. I could tell right away, by feel, that the spring was weaker than what I was expecting and replaced it.

I suppose you could use a trigger pull gauge using the technique above on a new spring (installed) and then check it against other bolts. Yep, not definitive by any stretch, but I've never known any other way. Perhaps the knowledge base here will enlighten us.
MistWolf
05-22-21, 22:48
Flick test. Remove the BCG from the rifle. Insert the rim of an empty case under the extractor and with your finger on the mouth of the case, compress the ejector. Then, flick your finger back and let the empty go flying. It should go about ten or twelve feet.
georgeib
05-23-21, 05:24
Flick test. Remove the BCG from the rifle. Insert the rim of an empty case under the extractor and with your finger on the mouth of the case, compress the ejector. Then, flick your finger back and let the empty go flying. It should go about ten or twelve feet.Nice. Been wondering how.
titsonritz
05-23-21, 15:33
I just use a pin punch to push the ejector into the bolt, if it feels like mush is needs to be replaced.
vicious_cb
05-24-21, 01:41
I just use a pin punch to push the ejector into the bolt, if it feels like mush is needs to be replaced.

Pretty much this, it should be a bi*ch it push in with just your fingers combined that with seeing where your brass lands should tell you if your spring has gone bad.
mark5pt56
05-24-21, 06:16
I little tidbit to accomplish two task with one act. After cleaning the bolt, place a drop of your favorite monkey jizz on the ejector and press the ejector in(I like to use the cam pin) 3-4 times to test the tension and get lube into the ejector pocket.
lysander
05-25-21, 15:20
The force required to push the ejector flush to the breech face should be 9.9 pounds . . .
prepare
05-25-21, 17:09
The force required to push the ejector flush to the breech face should be 9.9 pounds . . .

What is the method for checking that?
lysander
05-26-21, 11:42
What is the method for checking that?

https://images-na.ssl-images-amazon.com/images/I/31sTmhY5WbL.jpg
prepare
05-27-21, 21:09
https://images-na.ssl-images-amazon.com/images/I/31sTmhY5WbL.jpg

I haven't seen any Armorers use anything like that.
lysander
05-28-21, 20:58
Armorers? They just see if it flicks the case a few feet.
Spooky1
05-29-21, 10:58
I have always taken a EMPTY cartridge and done the "Flick Test" .

Mine usually fly 6 to 7 ft. because I use a Sprinco Ejector and Extractor spring, between those 2 she will get a cartridge out of the rig.

Or tare the damn extraction grove off the cartridge under the extractor. 😁
ViniVidivici
05-29-21, 14:47
Armorers? They just see if it flicks the case a few feet.

And that's all the ejector needs to do.

Using a trigger pull gauge on an ejector is classic overthinking.
georgeib
05-29-21, 17:04
And that's all the ejector needs to do.

Using a trigger pull gauge on an ejector is classic overthinking.

Except that the gauge tells you how soon the spring is going to be out of spec. Numbers don't lie, and are much more concrete than "good 'nuf."
prepare
05-29-21, 17:14
Except that the gauge tells you how soon the spring is going to be out of spec. Numbers don't lie, and are much more concrete than "good 'nuf."
What kind of gauge do you use?
georgeib
05-29-21, 17:47
What kind of gauge do you use?Same one as you. [emoji12]
prepare
05-29-21, 17:55
Same one as you. [emoji12]

What is that supposed to mean?
georgeib
05-29-21, 17:58
What is that supposed to mean?As I'm merely an enthusiast and neither an armorer, nor a 'smith, I don't own a gauge; just like you.
Spooky1
05-29-21, 18:17
What is that supposed to mean?

The local smith close to me basically goes by feel and flicking a empty case. He is the go to dude around home. About all he works on is AR's and AK's that is his thing.

Also I enjoy your posts, you ask alot of tech questions and I really enjoy reading the answers.

Thanks.
DG23
05-29-21, 20:36
Except that the gauge tells you how soon the spring is going to be out of spec. Numbers don't lie, and are much more concrete than "good 'nuf."

The gauge in the picture appeared to me to be able to measure weight pushing or pulling. Neat way to measure such a small spring...
prepare
05-30-21, 02:37
The local smith close to me basically goes by feel and flicking a empty case. He is the go to dude around home. About all he works on is AR's and AK's that is his thing.

Also I enjoy your posts, you ask alot of tech questions and I really enjoy reading the answers.

Thanks.

I'm just grateful when people share their knowledge and expertise and I appreciate your comment.
Spooky1
05-30-21, 08:02
I'm just grateful when people share their knowledge and expertise and I appreciate your comment.

I wish I had more information for you tho, & I am also grateful for the knowledge folks share, this is a awesome place to learn.
99cobra2881
05-31-21, 23:36
http://diy-defense.blogspot.com/2015/05/ar-15-ejector-removal-jig.html?m=1

Figure this is relevant to this post, a 300BO case will snap right over the 5/16 all thread. This jig makes ejector spring changes much easier.

5/16”x2” brass bolts are in most every toilet setting kit aka Johnny Bolts. I had a tough time finding individual 5/16” brass bolts at the local hardware stores. No need to search just get a toilet bolt kit.

This is the kit to mount the bowl to the floor not the bowl to the tank.
Spooky1
06-01-21, 00:20
http://diy-defense.blogspot.com/2015/05/ar-15-ejector-removal-jig.html?m=1

Figure this is relevant to this post, a 300BO case will snap right over the 5/16 all thread. This jig makes ejector spring changes much easier.

5/16”x2” brass bolts are in most every toilet setting kit aka Johnny Bolts. I had a tough time finding individual 5/16” brass bolts at the local hardware stores. No need to search just get a toilet bolt kit.

This is the kit to mount the bowl to the floor not the bowl to the tank.

Thank you for that, I have everything to make one except the 300 BO Case and I can fix that soon as I get to my Girlfriends house this evening.
the AR-15 Junkie
12-23-23, 20:04
What is the method for checking that?

https://www.youtube.com/watch?v=MjE50cBXUXM&t=76s
meganeura
01-04-24, 14:30
I haven't posted in years, but still follow the forum. In any case, I have Nidec-Shimpo MFD-05 that measures up to 45lb. I checked a spare SAA AR-15/M16 nitride bolt assembly I have. I carefully pushed straight in on the ejector until it was depressed to be even with the bolt face. I checked it three times, and I got 12lbs each time.