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kevinR
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Posted: 9/16/2012 9:28:13 PM

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Other than the mags (lets just say that we ruled that out as a possibility). I was a the range yesterday and had double feeds like no tomorrow. I did have a brass catcher on and I took it off thinking that the brass was being thrown back into the action causing things to get all jammed up. Once the brass catcher was off it still double feed. No all of the time mind you but more than I have ever experienced. I used some pretty good mags as well (C Products steel, man pull P mags, ect) I really don't think that it was the mags that caused the issue. Other then the mags what causes double feeds? Is there something in particular that I should be looking at? TIA
RedFalconBill
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Posted: 9/16/2012 9:35:10 PM
http://www.ar15.com/content/page.html?id=113

Double Feed/ 2F

Defined as two live rounds trying to feed into the chamber at the same time. A live round feeding into the rear of a fired round is a FtEx. The magazine is at fault 99.9% of the time. The other .1% is caused by over function causing the bolt to strike the inside of the LRE hard enough to jar rounds from the magazine. This is often seen on rifles with over large gas ports and weak buffer springs with light buffers.
kevinR
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Posted: 9/16/2012 9:41:21 PM
Originally Posted By RedFalconBill:
http://www.ar15.com/content/page.html?id=113

Double Feed/ 2F

Defined as two live rounds trying to feed into the chamber at the same time. A live round feeding into the rear of a fired round is a FtEx. The magazine is at fault 99.9% of the time. The other .1% is caused by over function causing the bolt to strike the inside of the LRE hard enough to jar rounds from the magazine. This is often seen on rifles with over large gas ports and weak buffer springs with light buffers.


Ya I show also tell you guys that the fired round did not eject but the live round was right behind it. I really did use good mags I really dont think that the mags are the issue ( I could be wrong however). Here was what I was shooting. I had 24.0 grains of H335 all mixed cases, CCI 400 primers, pulled 55 grain FMT BT grade 2. Now there is enough powder to function the action for sure but guys I had double feeds like crazzy I tell you.
kevinR
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Posted: 9/16/2012 9:41:58 PM
Originally Posted By RedFalconBill:
http://www.ar15.com/content/page.html?id=113

Double Feed/ 2F

Defined as two live rounds trying to feed into the chamber at the same time. A live round feeding into the rear of a fired round is a FtEx. The magazine is at fault 99.9% of the time. The other .1% is caused by over function causing the bolt to strike the inside of the LRE hard enough to jar rounds from the magazine. This is often seen on rifles with over large gas ports and weak buffer springs with light buffers.


what is the "LRE"?
mb3
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Posted: 9/16/2012 9:53:14 PM
Originally Posted By kevinR:
Originally Posted By RedFalconBill:
http://www.ar15.com/content/page.html?id=113

Double Feed/ 2F

Defined as two live rounds trying to feed into the chamber at the same time. A live round feeding into the rear of a fired round is a FtEx. The magazine is at fault 99.9% of the time. The other .1% is caused by over function causing the bolt to strike the inside of the LRE hard enough to jar rounds from the magazine. This is often seen on rifles with over large gas ports and weak buffer springs with light buffers.


Ya I show also tell you guys that the fired round did not eject but the live round was right behind it. I really did use good mags I really dont think that the mags are the issue ( I could be wrong however). Here was what I was shooting. I had 24.0 grains of H335 all mixed cases, CCI 400 primers, pulled 55 grain FMT BT grade 2. Now there is enough powder to function the action for sure but guys I had double feeds like crazzy I tell you.


There is your problem, a FTE. I would look at the extractor, extrator spring and lastly the ejector. If the fired round does not get out of the way the next round in line has nowhere to go. I know some dont like them but I run the extra power extractor springs with the black O ring, and I have not had any issues with extraction.
RedFalconBill
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Posted: 9/16/2012 10:09:54 PM

Originally Posted By kevinR:
Originally Posted By RedFalconBill:
http://www.ar15.com/content/page.html?id=113

Double Feed/ 2F

Defined as two live rounds trying to feed into the chamber at the same time. A live round feeding into the rear of a fired round is a FtEx. The magazine is at fault 99.9% of the time. The other .1% is caused by over function causing the bolt to strike the inside of the LRE hard enough to jar rounds from the magazine. This is often seen on rifles with over large gas ports and weak buffer springs with light buffers.

what is the "LRE"?

Lower Receiver Extension, ie the buffer tube
d1jinx
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Posted: 9/16/2012 10:14:22 PM
Sunds like your extractor
Darkness there and nothing more......
RedFalconBill
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Posted: 9/17/2012 11:22:51 AM

Originally Posted By kevinR:

Ya I show also tell you guys that the fired round did not eject but the live round was right behind it. I really did use good mags I really dont think that the mags are the issue ( I could be wrong however). Here was what I was shooting. I had 24.0 grains of H335 all mixed cases, CCI 400 primers, pulled 55 grain FMT BT grade 2. Now there is enough powder to function the action for sure but guys I had double feeds like crazzy I tell you.

24.0gr of H-335 is a rather low powdered handload and I would not use CCI-400 primers in an AR.
kevinR
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Posted: 9/17/2012 10:32:00 PM
Originally Posted By RedFalconBill:

Originally Posted By kevinR:

Ya I show also tell you guys that the fired round did not eject but the live round was right behind it. I really did use good mags I really dont think that the mags are the issue ( I could be wrong however). Here was what I was shooting. I had 24.0 grains of H335 all mixed cases, CCI 400 primers, pulled 55 grain FMT BT grade 2. Now there is enough powder to function the action for sure but guys I had double feeds like crazzy I tell you.

24.0gr of H-335 is a rather low powdered handload and I would not use CCI-400 primers in an AR.

?

I get 23.2 grains of H335 to cycle the actions of my 4 AR's 100% of the time, so I would think that 24.0 grains is even better to cycle the action if 23.2 grains is getting it done. Why would you not use CCI 400 primers?
RedFalconBill
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Posted: 9/17/2012 11:12:32 PM

Originally Posted By kevinR:
Originally Posted By RedFalconBill:

Originally Posted By kevinR:

Ya I show also tell you guys that the fired round did not eject but the live round was right behind it. I really did use good mags I really dont think that the mags are the issue ( I could be wrong however). Here was what I was shooting. I had 24.0 grains of H335 all mixed cases, CCI 400 primers, pulled 55 grain FMT BT grade 2. Now there is enough powder to function the action for sure but guys I had double feeds like crazzy I tell you.

24.0gr of H-335 is a rather low powdered handload and I would not use CCI-400 primers in an AR.

?

I get 23.2 grains of H335 to cycle the actions of my 4 AR's 100% of the time, so I would think that 24.0 grains is even better to cycle the action if 23.2 grains is getting it done. Why would you not use CCI 400 primers?

CCI 400 primers do not have a thick enough cup to handle the pressures of 5.56 and 24.0gr is anywhere from a starting load, to near starting load. What velocity are you getting when you chronograph your handloads?

25.0gr would be a better load and I would migrate over to a 450/BR4, Fed 205M, or Remington 7 1/2.

Does your AR malfunction with factory ammo?
kevinR
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Posted: 9/18/2012 8:36:48 PM
Originally Posted By RedFalconBill:

Originally Posted By kevinR:
Originally Posted By RedFalconBill:

Originally Posted By kevinR:

Ya I show also tell you guys that the fired round did not eject but the live round was right behind it. I really did use good mags I really don't think that the mags are the issue ( I could be wrong however). Here was what I was shooting. I had 24.0 grains of H335 all mixed cases, CCI 400 primers, pulled 55 grain FMT BT grade 2. Now there is enough powder to function the action for sure but guys I had double feeds like crazy I tell you.

24.0gr of H-335 is a rather low powdered hand load and I would not use CCI-400 primers in an AR.

?

I get 23.2 grains of H335 to cycle the actions of my 4 AR's 100% of the time, so I would think that 24.0 grains is even better to cycle the action if 23.2 grains is getting it done. Why would you not use CCI 400 primers?

CCI 400 primers do not have a thick enough cup to handle the pressures of 5.56 and 24.0gr is anywhere from a starting load, to near starting load. What velocity are you getting when you chronograph your hand loads?

25.0gr would be a better load and I would migrate over to a 450/BR4, Fed 205M, or Remington 7 1/2.

Does your AR malfunction with factory ammo?


Did not have any factory loads with me on the last outing but as far as chrono on average sir I have wrote down 2801 FPS and that is out of a M-4 profile barrel.
RedFalconBill
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Posted: 9/18/2012 9:01:32 PM

Originally Posted By kevinR:

Did not have any factory loads with me on the last outing but as far as chrono on average sir I have wrote down 2801 FPS and that is out of a M-4 profile barrel.

M-193 out of a 16" barrel will average 3,075fps +/- 25fps. Even taking off ~100fps for .223 data, you are a bit low. Bumping up the charge to 25.00gr will result in ~12 fewer reloads per pound of H-335.

Now as for the fired round not being extracted, I would check your extractor and spring to see if it has enough tension because it sounds like the lip is sliding off of the rim. If the extractor is GTG, then replace the spring and insert with the kit from BCM (under $5.00).
kevinR
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Posted: 9/20/2012 8:43:36 PM
Originally Posted By RedFalconBill:

Originally Posted By kevinR:

Did not have any factory loads with me on the last outing but as far as chrono on average sir I have wrote down 2801 FPS and that is out of a M-4 profile barrel.

M-193 out of a 16" barrel will average 3,075fps +/- 25fps. Even taking off ~100fps for .223 data, you are a bit low. Bumping up the charge to 25.00gr will result in ~12 fewer reloads per pound of H-335.

Now as for the fired round not being extracted, I would check your extractor and spring to see if it has enough tension because it sounds like the lip is sliding off of the rim. If the extractor is GTG, then replace the spring and insert with the kit from BCM (under $5.00).


How do I test the extractor? TIA
RedFalconBill
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Posted: 9/20/2012 9:25:12 PM

Originally Posted By kevinR:

How do I test the extractor? TIA

Inspect it visually for any cracks, nicks, burrs, on the hook portion. If it is GTG, then replace the spring and insert. You also might look at your buffer spring and buffer weight.