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Posted: 1/10/2009 12:42:20 AM EDT
At our last match we were picking up our brass and the fellow next to me said that it was possible to make the brass fall in one nice pile and not fly 6 feet out the side of the gun.  After reading up i see that some guys trim the ejector spring a bit to tame the flying brass.

Anyone do this and does it work as advertised?  If so, how do you do it?
Link Posted: 1/10/2009 12:53:22 AM EDT
[#1]
you can use a carrier weight system and that slows the carrier down as well
be carefull in trimming the spring to short and it wont operate properly
Link Posted: 1/10/2009 2:31:30 AM EDT
[#2]
Before you start shortning tne ejector spring, do your self a favor and buy a few replacement springs. That way if you get it too short, you can cut the next one a slight bit longer.
The spring that came in my Rock River NM upper was a few turns shorter than stock to start. It still threw them a good distance though.

I did mine about 3 years ago, and now the spring is getting just a tad too weak for my liking. I am going to replace it this winter.

Start by cutting about 2 1/2 turns off of the spring.
reassemble, and test fire it.
If you feel it needs more, cut 1/2 turn off at a time, test firing as you go.

It takes a little time, but is well worth it.

Also, the guy on your right on the line won't be getting a hot brass shower.

Pete A.
Link Posted: 1/10/2009 6:17:53 AM EDT
[#3]
I had to trim off less than Gunguy only 1.5 coils needed on mine .Do a search there was a good and lengthy thread about this a while ago

Tim
Link Posted: 1/10/2009 6:21:27 AM EDT
[#4]
I say put in a stronger spring and let the rifle eject more to the rear. Cutting ejector spring will sooner or later lead to ejection problems. There is no way to "fine tune" it for all occasions. Too many variables and some are bound to change. You will have to periodically futz with that spring or accept occasional malfunctions. I tried it for 3 years and decided that it's not worth it. I believe Holliger is not doing this for the same reason. Again, sooner or later you will pay for that convenience with saved rounds in rapid fire.
Link Posted: 1/10/2009 8:09:15 AM EDT
[#5]
I did mine back in '94, have gone through 4 Bbls, and have not had to "futz" with it at all. I cut mine to where the ejector sticks up about .030 above the rim of the bolt
Never had a FTE because of it,, the brass ejects about a foot at 1:00 when in prone and pick up all my brass without going in front of the FL, and about 4 foot at 1:00 in OH, all in a neat pile
'Borg
Link Posted: 1/10/2009 8:24:56 AM EDT
[#6]
Here's a link about trimming the ejector spring.  The BM DCM's have the spring trimmed 2 coils which thru the brass at about 2:00.  My std bolt throws it at 4-5:00.  I wouldn't trim past the 2 coils if you do decide to trim and if you do, keep an eye on it to replace as needed per Lenny's point.  Although I have not had any problems with it trimmed 2 coils with over 2k rounds and counting.

mince
Link Posted: 1/10/2009 8:33:59 AM EDT
[#7]
Quoted:
I say put in a stronger spring and let the rifle eject more to the rear. Cutting ejector spring will sooner or later lead to ejection problems. There is no way to "fine tune" it for all occasions. Too many variables and some are bound to change. You will have to periodically futz with that spring or accept occasional malfunctions. I tried it for 3 years and decided that it's not worth it. I believe Holliger is not doing this for the same reason. Again, sooner or later you will pay for that convenience with saved rounds in rapid fire.

That is just not the case, or maybe I am misunderstanding this tech note from Armlite.

The ejection pattern of a rifle is created by a complex interplay of the opening velocity of the
carrier group, and the extractor, ejector and their springs. In general, the faster the carrier
group opens, or the stronger the extractor and ejector springs, the farther toward 12:00
(looking down on the rifle) the case is ejected.
The weaker the springs are, or the slower the
carrier group opens, the farther toward 6:00 the case is ejected.

Link Posted: 1/10/2009 9:33:20 AM EDT
[#8]
Weaker ejection spring will through the brass more toward targets, at about 1:00-2:00 O'Clock. Targets are at 12:00 O'Clock. The note from Armlite is in error.
Link Posted: 1/10/2009 9:59:49 AM EDT
[#9]
Quoted:
I did mine back in '94, have gone through 4 Bbls, and have not had to "futz" with it at all. I cut mine to where the ejector sticks up about .030 above the rim of the bolt
Never had a FTE because of it,, the brass ejects about a foot at 1:00 when in prone and pick up all my brass without going in front of the FL, and about 4 foot at 1:00 in OH, all in a neat pile
'Borg


Ken,
We will never convince each other. Cutting ejector spring was one of "to do" things when AR became popular in highpower. More and more people are walking away from it. You either were very lucky or misdiagnosing the causes for mulfunctions you might have had in those 15 years. BTW, FTE is not always obvious. The feeding round often pushes an empty case out and jams while doing so. You don't always find empty case in your action. Only 4 barrels in 15 years? I go through 3 barrels in two years.
Link Posted: 1/10/2009 10:47:54 AM EDT
[#10]
Quoted:
Quoted:
I did mine back in '94, have gone through 4 Bbls, and have not had to "futz" with it at all. I cut mine to where the ejector sticks up about .030 above the rim of the bolt
Never had a FTE because of it,, the brass ejects about a foot at 1:00 when in prone and pick up all my brass without going in front of the FL, and about 4 foot at 1:00 in OH, all in a neat pile
'Borg


Ken,
We will never convince each other. Cutting ejector spring was one of "to do" things when AR became popular in highpower. More and more people are walking away from it. You either were very lucky or misdiagnosing the causes for mulfunctions you might have had in those 15 years. BTW, FTE is not always obvious. The feeding round often pushes an empty case out and jams while doing so. You don't always find empty case in your action. Only 4 barrels in 15 years? I go through 3 barrels in two years.

LOL,, that's just ONE of my three uppers that have pinned sights, I've had it modified the longest. I didn't get back into HP till 2004 after leaving in 1985.
The only jams I've had was due to a mag that had been dropped on concrete and bent the lip, or, once, when I didn't slap a tight fitting mag in all the way.
I've shot next to too many people that haven't cut their spring, and end up with hot brass against my leg or thigh, leaving burns.
I'm not going to subject someone else to that kind of treatment.
'Borg
Link Posted: 1/10/2009 11:14:10 AM EDT
[#11]
Eject to the rear. It will clear the shooter next to you and will not compromise reliability of your rifle. That's why I started off by advising to get a stronger ejection spring. In prone you can block ejected brass with your shooting stool.
Link Posted: 1/10/2009 12:28:12 PM EDT
[#12]
I have a NM weighted carrier with an extra power recoil spring in my rifle and my brass goes nicely to the rear at about 5:00.

Armalite's tech note is for the AR-10, but I figured it should be the same for AR-15.
My AR-10 used to throw all the cases to far forward in the long grass at the range making recovery tedious.  I followed their instructions and clipped off some ejector spring coils, and it brought the ejection pattern rearward, and also stopped denting the cases.  That is my only experience with ejector tuning, I don't need to mess with my Ar-15, as they pretty much miss the guy to my right.

Link Posted: 1/10/2009 12:54:51 PM EDT
[#13]
5:00 O'Clock ejection is optimum. Sometimes that's what you get out of the box. If the rifle ejects at 3:00, the easiest solution is to change the ejector spring. Different manufacturers use different springs at different times. I was able to find a stronger spring from a different manufacturer. There are also chrome silicone springs advertised as extra power. I never shot AR-10, so I don't know.
Link Posted: 1/10/2009 1:15:42 PM EDT
[#14]
I have been cutting ejector springs for several years in my AR's and for others. No problems. My oldest upper is on it's third barrel.
If you a lefty, performing this will really help you!

I do cut mine off very neatly and square with a Dremel Tool and a cut off wheel. Some do theirs with side cut pliers. Just be sure the end of the spring is not distorted and remains the same contour of the remainder of the the spring when you are finished.

Myself, I am courteous to other competitors when on the firing line. I don't bury the shooter to the right of me with my brass. In other words, I practice good range etiquette! Also, I always get my brass in the allowed time permitted for policing, most times even before, as they can all be found in a neat pile out at 1 o'clock. In prone, just about a foot away from the rifles ejection port.

Now when I get buried or repeatedly pelted by a competitor's AR brass, well since I am so courteous on the line, I kindly help them police their brass by throwing it back at them! Like here you go bud. Sometime, hopefully in the near future they will get the message and cut their ejector spring.

Dave McGrath
Link Posted: 1/10/2009 9:52:34 PM EDT
[#15]
I used a dremel cutoff wheel and took about 1 1/2 coils from the spring.  I'll try to shoot it this week to see how it works.  I will order a couple extra springs in case it doesnt work out, springs are less than the shipping, go figure..  Anywhay if it keeps my brass from flying 8 feet down the line and pelting the next fellow then Im happy.  I hate looking all over the line for my brass.
Link Posted: 1/11/2009 9:17:12 AM EDT
[#16]
Rest assured, it works
Try your rifle in the prone position. Your goal is to get your rifle "potty trained" to eject your brass out at 1 o'clock. If your brass is out at 3 o'clock, cut off another full coil. If your brass is out at 2 o'clock, cut off another 1/2 coil.

I usually take off two coils but some rifles need three full coils taken off.

Dave McGrath
Link Posted: 3/8/2009 9:32:20 AM EDT
[#17]
Now I am a believer.

I am tired of chasing brass down and not finding all of it in a timely fashion so I took a brand new spring, cut 2 coils off, and replaced the one in my RRA NM bolt.  The next time out to the range it was still chucking them at almost 4:00, so I clipped another 1/2 of a coil, and wound up repeating the process one more time after that.

This morning at our practice match, I noticed that all my brass was collecting in front of me at about 1:00, and less than 2' away from my rifle.  I found every case in a snap, and had the curiosity of other shooters on the line.  It also got me out of the rain that much sooner.
Link Posted: 3/21/2009 3:38:05 PM EDT
[#18]
tag.
Link Posted: 3/21/2009 9:16:49 PM EDT
[#19]
I TELL NO STORIES!

I have posted here and at other sites over the years on this modification and I am glad to see it wasn't all in vain.
Now, maybe those "sharp" assemblers that are reaping your hard earned dollars will incorporate this into your next "build????".
Ya, right! Well, maybe for an extra $$$$$

Dave McGrath
Link Posted: 3/22/2009 6:25:13 PM EDT
[#20]
I have made a brass deflector that mounts on a a2 carry handle and dumps all brass approx 1 ft away without jamming the rifle as it deflects it outside of the ejection port area.
Link Posted: 3/29/2009 1:03:41 PM EDT
[#21]
brdvictim;
You may have an external modification. Not legal for service rifle.

Dave McGrath
Link Posted: 5/2/2009 11:20:18 AM EDT
[#22]
Just a little update.  Since trimming my spring my rifle is still piling brass neatly at 1:00 for the last several matches.  Best mod you can do IMHO, besides the gas seal on the charging handle with RTV..
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