Dented case on ejection

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  • #16
    Originally posted by BjornF16 View Post
    Sorry, let me be more precise. The case was extracted from the chamber in all cases but was not ejected properly.

    Four shots resulted in spent case remaining loosely just above magazine. This of course interfered with insertion of next cartridge (this occurred twice). I then shot with empty magazine inserted three times. Twice the result was loose cartridge sitting on top of magazine with bolt locked back. Once the case was properly ejected.
    It sounds like the spring is now too short. I hope you have another and can trim it less.
    Bob

    Comment

    • BjornF16
      Chieftain
      • Jun 2011
      • 1825

      #17
      I trimmed enough spring to leave it protruding just under 1/16" beyond face (I left a little more than the instructions said). I'll swap out the spring after trimming the new one by half as much.

      I did go back to the range after opening up the gas block more...no difference. I gather there is a difference between 5.56 and 6.5 when it comes to ejector force?...
      LIFE member: NRA, TSRA, SAF, GOA
      Defend the Constitution and our 2A Rights!

      Comment

      • rasp65
        Warrior
        • Mar 2011
        • 660

        #18
        Bjorn I have done it to both 6.5 and 5.56 bolts in both cases I left it longer than what the instructions said. I think that I removed 2 or 3 coils depending how you look at the spring. I wanted to make sure I didn't take too much off especially since the spring is kind of hard to hold securely,as you probably found out.

        Comment

        • sneaky one
          Chieftain
          • Mar 2011
          • 3077

          #19
          Try an extractor up-grade, such as the D-fender, to eliminate extraction problems, my AA upper was a nightmare first time at the range-same as yours, bjorn = empty brass on top of fresh round in mag., then zero extraction. I felt the need to send the upper back. A new D-fender cured that. As far as the ejector spring- cut 1.5- 2 coils-then leave it alone.

          Comment


          • #20
            1) Examine the face of the spent brass (primer side). Is there a small mar the size of the ejector pin? If so this is an indication that the spring force is to high on the ejector pin. (Use advise given above to solve problem)
            2) Examine the spent brass groove (where the extractor hook grips the brass). Is there marring and digs in the brass? If so you could have a problem with the extract hook digging into the brass and not letting it go like it should when flinging the brass out which. This could cause it to rotate around and dent on the extractor itself. Investigate if you need to de-burring the extractor hook and determine if you have the correct bolt & extractor for the headspace of this barrel. The AA barrel’s are head spaced for their own bolt and extractor combination (AA bolts are milled .011” deeper and a custom, improved extractor is used with the bolt. This will not work correctly with a barrel that is headspaced for a standard AR .30 cal bolt (.454 bolt depth, and .136 diameter).
            3) When your brass lands forward of 3:00 it is often an indication that the brass is bouncing off of the deflector or the like which sends the brass forward landing at 2:00. This is either due to over gassing or ejector issues usually. (The over gassing throws it further toward the 5:00 but if it is bouncing of the gun it will land more at 1:00 or 2:00)
            I initially had the same dents on my brass when breaking in the system. It was due to over gassing. I have a Mega side charge upper which has a sharp corner where the brass ejection port and side charge slot intersect. The brass was being flung right into this corner creating the dent and then bouncing forward to 2:00. I did 2 things to fix this. 1) Swapped the buffer out from a carbine buffer to a T2 (using a Spkies ST2). The heavier buffer slows down the velocity of the bolt carrier slightly. 2) Secondly I dialed down my PRI adjustable gas all the way to closed and opened it incrementally until it had just enough gas to reliably cycle the bolt. On my system this was .5 turns from closed. Running the carrier as slow as you can in my opinion saves on wear and tear and your gun and loads the round a little more consistently because it reducing the slamming effect which can only help with accuracy.

            Comment

            • samalama76

              #21
              OK. Maybe I missed it, but what is causing the dented case mouth? I have this on almost all my spent casing and it is not a huge problem, but it is very irritating. Please advise or call me an idiot and refer me to the post that explains it. Thanks in advance.

              Comment

              • bwaites
                Moderator
                • Mar 2011
                • 4445

                #22
                No idiocy! Two things cause it:

                1) Most commonly it is striking the deflector behind the ejection port. That's why the deflector is there. If you don't like the dented case mouths, put a piece of the loop (soft) side of velcro there and it will disappear.

                2) Cases striking the concrete. Obvious fix, don't shoot on hard surfaces.....LOL.

                There is a permanent fix, and that requires shortening the ejector spring very slightly, and there is a link to directions on how to do that on the board.

                Comment


                • #23
                  you may have trimmed the spring too short, but you may be fine with a gas adjustment. many things can affect ejection/extraction, I usually go very little on the ejector spring to check the reaction, usually do it at the range, since you also have an adjustable gas block, put some more gas through it

                  on your last shot did the bolt lock open? try shooting one shot at a time from the mag and see if your bolt locks open and if the rounds eject, increase gas slowly to see what happens and if you can get the rounds to eject and what the angle is, then load up a magazine with 5 rounds and try again

                  Comment

                  • BjornF16
                    Chieftain
                    • Jun 2011
                    • 1825

                    #24
                    ejector springs.jpg


                    This is the pic of the ejector springs: Top is the original size; bottom was my first attempt at reducing size (which resulted in no ejections); middle is my second attempt at reducing size.

                    I plan on going to the range today and will report back findings.
                    LIFE member: NRA, TSRA, SAF, GOA
                    Defend the Constitution and our 2A Rights!

                    Comment

                    • sneaky one
                      Chieftain
                      • Mar 2011
                      • 3077

                      #25
                      Did you change the extractor spring? At least bring a new one and the tools to swap it out at the range. Most people are very helpful at the range-if you need the extra 3 hands., they will step up. Good luck, we all hate an unreliable rifle.

                      Comment

                      • BjornF16
                        Chieftain
                        • Jun 2011
                        • 1825

                        #26
                        Range report: New spring (trimmed by 1.5 coils) = proper ejection.

                        The first case ejected had the body dent...reduced the gas and the cases did not have the dent (nor collapsed neck). The cases are still ejected further than I'd like but there is no damage to the spent cases (which is the main goal).

                        Have not messed with extractor spring and have no intentions.
                        LIFE member: NRA, TSRA, SAF, GOA
                        Defend the Constitution and our 2A Rights!

                        Comment


                        • #27
                          Good to know. Will have to tinker with mine. Thanks!

                          Comment

                          • sneaky one
                            Chieftain
                            • Mar 2011
                            • 3077

                            #28
                            Good job Bjorn, the ejector spring needs to stay close to stock length=1.5--2.0 coils cut- is all that's needed... I'll have to install the adj. gas block soon. I guess you got lucky on extractor spring issues, for now....

                            Comment

                            • BjornF16
                              Chieftain
                              • Jun 2011
                              • 1825

                              #29
                              Originally posted by sneaky one View Post
                              I guess you got lucky on extractor spring issues, for now....
                              My "other" Grendel is an AA Entry...no extraction issues whatsoever. I'll probably trim its ejector spring 1.5 coils since it also has a propensity to deform spent case necks. I wish I had an adjustable block for it...
                              LIFE member: NRA, TSRA, SAF, GOA
                              Defend the Constitution and our 2A Rights!

                              Comment


                              • #30
                                Hey i am new to site but i have had trouble with dented brass went through alot trying to figure out why it was shaving brass and denting the brass i changed the buffer spring to try and slow cycle changed stock buff and spring agian did not change sent it to jt said it was fine and sent me adjustable gas block wrong size so gave up at that point me and a buddy was reloading some brass and tried a littel hotter load and guess what the brass came out with no dents my load was 123 amax hodgdon blc2 powder 31.8 grains cci primer it tighted up my group to 100 yards 3 shots dime size

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