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Posted: 8/16/2007 9:45:30 PM EDT
| I just installed the BCM upgrade kit and my rounds will not eject from bolt.With the bolt out I can insert round,not easily,flush to bolt face and it stays there,like the extractor claw has too much hold on it.Any suggestions please. |
Going Sat. am,will report.
+1 I just did a lot of experimenting using the Wolff HighPower Extractor 5 coil spring, the rubber "O" Ring (Actually it's maded of a material called "Viton") and the Black Extractor insert. By the way...I didn;t have any problems before I started "messing with it". I had several Failures to Eject with the rounds barely making it out of the receiver and falling around my right foot. After extensive research, I talked to LMT who manufacutred my 16" MRP and they recommend only the "Black" extractor buffer and a Mil Spec Extractor Spring (which is what came with the upper on both bolts I purchased, with no "O" ring. This is because the performance upgrade is for barrels that are shorter than 16", like a 14" M4 barrel or shorter, or for suppressed weapons. I don't understand why, but I think it has to do with increased recoil force in the shorter and suppressed weapons. To make a long story shorter....everything runs 100% with just the Black Extractor buffer and standard 4 coil extractor spring, and the ejected rounds fly about 10 feet away at the 3 O'clock position every time now. This is what you want in any semi auto. Get that brass way out and away from the gun at ejection. Tack |
+1 I just did a lot of experimenting using the Wolff HighPower Extractor 5 coil spring, the rubber "O" Ring (Actually it's maded of a material called "Viton") and the Black Extractor insert. By the way...I didn;t have any problems before I started "messing with it". I had several Failures to Eject with the rounds barely making it out of the receiver and falling around my right foot. After extensive research and "Tinkering", I talked to LMT who manufacutred my 16" MRP and they recommend only the "Black" extractor buffer and a Mil Spec Extractor Spring (which is what came with the upper on both bolts I purchased, with no "O" ring." This is because the BCM performance upgrade is for barrels that are shorter than 16", like a 14" M4 barrel or shorter, or for suppressed weapons. I don't understand why, but I think it has to do with increased recoil force in the shorter and suppressed weapons. To make a long story shorter....everything runs 100% with just the Black Extractor buffer and standard 4 coil extractor spring, and the ejected rounds fly about 10 feet away at the 3 O'clock position every time now. This is what you want in any semi auto. Get that brass way out and away from the gun at ejection. BTW...I now have about 90 Viton "O" rings which is what Crane uses as their "Donut" (I have done the research on this and Crane confirms that Viton is the material used in their "O" rings) that I have no need for until I get a shorter weapon, along with 10 Wolff HighPower Extractor Springs. I also have 1 Defender "D" Ring. All of these are just sitting around in my spare parts box. Tack |
There's plenty of pressure from the "Extractor", but IF you don't have a high power or "Fresh" EJECTOR Spring you won't get the ejection out of the receiver you might expect. That was my experience with a 16" barrel after extensive trial and error. Tack |
| Ok Quib,functioned fine except for the 3rd round and had no problems there on.On that 3rd one the bolt failed to lock up completely and i pulled the trigger and no bang.I pulled ch. handle and seen the round fully seated,returned to bat. and ejected that round.Round was dented and gouged pretty good,thinkig maybe the claw wasnt grabbing good and was just pushing the round in instead of locking it.That was the problem i had last night plus it wouldnt kick the round out.Dont know how to post pics yet.Any way all the rest ran good.I didnt install the o ring either. |
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Well, other than one instance, everything ran good? Like I said, I’ve installed the entire BCM kit in 3 separate carbines and never had a problem. I currently have a kit in my new SAM-R clone that will get it’s first taste of the range next week. Let's see what happens. |
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I just got a bolt and carrier with the BCM kit installed. I removed the Oring, it was just too much force with the Oring installed and the shells didn't want to eject properly. Also, With that much spring force it makes the foward assist almost unusable even without the Oring installed. BCM needs to include an extra power ejector spring with there extractor kit too, It would help fling the shell away from the extractor. |
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