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Posted: 6/2/2012 4:55:21 PM EDT
| I have a TJ 16 inch carbine length upper with pac nor barrel .The problem is fired cases hang on the extractor.doesnt matter what load or what bullet or powder being used..Dosent seem to be any burrs or sharp edges on extractor but does seem to leave heavy extractor marks on cases.Ejection is poor about 2 ft at 2oclock.I ve tried a new extractor spring and it was worse.reinstalled old one.buffer and spring is standerd A2.Has anyone bought bolts from SBR?Are they machined extractors or filed?I emailed them and ask and they dodged the question .Was told they have them in stock. |
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I have a TJ 16 inch carbine length upper with pac nor barrel .The problem is fired cases hang on the extractor.doesnt matter what load or what bullet or powder being used..Dosent seem to be any burrs or sharp edges on extractor but does seem to leave heavy extractor marks on cases.Ejection is poor about 2 ft at 2oclock.I ve tried a new extractor spring and it was worse.reinstalled old one.buffer and spring is standerd A2.Has anyone bought bolts from SBR?Are they machined extractors or filed?I emailed them and ask and they dodged the question .Was told they have them in stock. Does your extractor spring have an insert or O-Ring? When you say the extractor leaves "marks" on the cases, are they on the rim? I have a bolt from SBR (as a back-up) but have not installed or used it....so I can't say how it performs. My rifle is also a TJ and I've never had a problem with it. If you can post a picture of your bolt face and extractor (close up, use macro) we might be able to tell something, or at least compare it to others. Something to try...would be to hand cycle some rounds and see where they eject, I know you said it doesn't matter what bullet, powder, etc...you try, but a 16" Carbine gassed SOCOM will be overgassed in many cases and could be the source of your problem. IF you can hand cycle them and they eject properly, then it will let us look in a different direction than the extractor/bolt. |
| http://i796.photobucket.com/albums/yy247/bidwell01/000_0077.jpghttp://i796.photobucket.com/albums/yy247/bidwell01/000_0080.jpg]No o-ring on extractor.Spring is installed upside down. Is this normal position for the spring in the socom?The cases seem to be on the rim only .Ive tried cycleing by hand and round ejects about 4 inches out ejection port.I ve thought maybe ejector spring but it does have pressure on it so i havent pulled it apart yet for inspection. It does have some wear on the ejector tip itself?Flintknapper? Is the extractor on the SBR filed or machined?Just reinstalled new extractor spring with no -ring and round hangs on extractor everytime.This is with the spring installed properly. |
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There are two things that will cause that.
1. The bolt face has not been opened up large enough. Just because the case head can sit flat against the bolt face, doesn't mean you have enough clearance for it rotate out without binding. 2. The groove in the extractor is too narrow, or not cut up high enough. Again, just because the extractor hook can snap over the rim, doesn't mean you have enough clearance to allow the case to cleanly rotate out during ejection. I would also make sure that the case is not hitting the upper or lower edge of the ejection port. Even if it skims the surface, it will cause problems. Tony Rumore Tromix |
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need more info....
on the last round, even with the round stuck in the ejector, does the bolt lock back on the magazine? what gas system are you using, what gas block? this isn't necessarily a problem with the bolt/extractor/ejector, this could be a gas problem, or a buffer spring issue... need more info |
| Ok.I can measure the bolt face but what should it measure ?But i dont know what to do about extractor groove cause i have nothing to go by .I guess a new bolt from SBR is my only chance at this point. My question still needs answered on the extractor spring.Is the proper install of the spring upside down meaning does the fatter end go up or in the extractor cup? |
| Yes , bolt will lock back on last round if stuck on extractor. Carbine length gas with low pro gas block {what ever Marty used to build it}The buffer spring and buffer are standered A2 butt stock with standerd buffer spring and buffer.Ive got a Collapsible Stock with buffer spring and buffer im not useing i guess i can install it to see if it functions different with it. |
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Ok.I can measure the bolt face but what should it measure ?But i dont know what to do about extractor groove cause i have nothing to go by .I guess a new bolt from SBR is my only chance at this point. My question still needs answered on the extractor spring.Is the proper install of the spring upside down meaning does the fatter end go up or in the extractor cup? Duke, I am writing you something up right now and will include some pics. There are a couple of things we need to check...that revolve around what Tony said, he is spot on. Give me a few minutes. Flint. |
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Duke, let’s see if we can narrow down your problem by excluding a few potential problems. Your problem might not lie with the extractor, ejector or bolt…but we will address them first.
To answer one of your previous questions, NO the extractor spring is not supposed to be upside down, it should fit per normal as for a .223/5.56 I took my new SBR bolt (I keep for a spare) out of the package and compared it to the TJ bolt that came with my upper. The both look like standard DPMS bolts to me. 
Looking at the face of both you will see the required ‘opening/enlarging’ of the bolt face and fitting of the extractor. As you know… the bolt face must be opened up to receive the base of the cartridge AND the extractor must also be modified such that it fits the newly modified face of the bolt. The groove in the extractor will need to have clearance in two directions. Of course, it must be profiled after modifying also. 
One difference between the TJ bolt that came with my upper and the new SBR is some radius work. I put the SBR in my rifle and hand cycled 8 rounds with no problems, so it works just fine but the TJ bolt got some “extra” attention to insure reliability. We will talk about that later. 
Here you can see the SBR ejector (unmodified). It works fine. 
With the TJ bolt… the Ejector was radiused slightly moving the contact point outward toward the lugs. This gives it a slight mechanical advantage and lets the portion of cartridge lip under the extractor tilt a bit more instead of having so much upward pressure on it. Is it ‘necessary’, maybe not….but a thoughtful addition. Similarly, the edges of the of the extractor were beveled/radiused to allow for a smoother ‘lead-in’ when the extractor snaps over the case. It also leaves a little room for debris (dirt,brass, dust) to go to…. and hopefully be dislodged. This is just Marty…going the “extra mile” 
Continued next post: |
Now let’s do some simple testing to make sure your brass isn’t getting hung up anything related to the bolt. First thing you can do is to measure the bolt face opening. You should have a minimum of .4805” which is what both of my bolts measures, but is NOT a supplied specification. There should be a good amount of webbing still left between the locking lugs at this measurement.
The next thing I would have you do…is to simply hang a cartridge under the extractor (extractor in 12 O’Clock position) and see if it holds it there. Then turn the bolt 180° and see if the cartridge falls loose (it should). 
If you have no problems with the above then we want to check the bolt face opening and extractor tension by doing the following. Insert a case under the extractor (it should slide in easily). It will be in the position shown in the picture below (lip under extractor, ejector touching base of case keeping it in position shown). We are then going to pivot the case towards the ejector. 
You might need to use two hands to keep the lip of the case pressed against the extractor groove, but the case should pivot/rock freely back and forth. IF not then you have a problem in one of several areas. 
IF you feel the case rim dragging on the bolt face opening… then the opening is not large enough and/or the groove in the extractor is incorrect (not deep enough or not enough clearance in height). Also check to see that the extractor moves freely in its slot and that you have good spring pressure on the ejector (not extractor). Be sure the ejector moves freely in its bore. Come back and let us know what you find. One last thing, measure rims of your cases and be sure they are between .471 and .473 Flint. |
| I have had some SBR Bolts and they are touched up with a sander disk and all have been perfect. Tony is on, with the 2 possibilities, but the ejector has not been addressed, if it is sticking or the spring is week, then it can not do its part to push the case out. Another possibility is the corners on the extractor are a little to sharp and dig into the brass rim. You can sand a round edge on the corners without fear of damage. There is too much emphasis on over gasing when a problem comes up. |
| Ok.Bolt looks like your Tj bolt includeing the ejector.Thats where i said i thought the ejector had wear on it now i know thats how Marty built it.The bolt face measures .4778" which is larger than case rim but not as large as your bolt face.Now i reinstalled the new extractor spring properly insert case and does have play from side to side but feels like its binding alittle . Turning it to 12:00 it will not fall out even when i shake it as hard as i can.This tells me by the the way yours functions its improper extractor and possable bolt face isnt large enough {compared to both of yours}.Pushing the case out of bolt it feels rough comeing out of extractor and feels rough around case rim not as bad tho as if i fired the round.Case rim measure the same as your . |
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Duke, without having your parts in hand...to measure and compare, I can't say for certain where the problem lies, but it sounds like your bolt face (and maybe extractor) are running on the tight side.
If it were me, I would call Buddy at SBR and see if you can send your bolt to him for inspection and possible 'dressing'. You might want to order a new one to have as a spare while you are at it. SBR 140 INDIGO DR BRUNSWICK, GA 31525-6854 (912) 264-5822 |
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Ok.Bolt looks like your Tj bolt includeing the ejector.Thats where i said i thought the ejector had wear on it now i know thats how Marty built it.The bolt face measures .4778" which is larger than case rim but not as large as your bolt face.Now i reinstalled the new extractor spring properly insert case and does have play from side to side but feels like its binding alittle . Turning it to 12:00 it will not fall out even when i shake it as hard as i can.This tells me by the the way yours functions its improper extractor and possable bolt face isnt large enough {compared to both of yours}.Pushing the case out of bolt it feels rough comeing out of extractor and feels rough around case rim not as bad tho as if i fired the round.Case rim measure the same as your . Hey guys, sorry about the absence, just got back 0700 this morning. The extractor spring is installed "upside down" on purpose, this gives the extractor just a little more room to cam should it need it. So I would suggest installing it "wrong", it still gives ample leverage to remove the case. Also, no O-rings, D-rings, etc. From your bolt measurement, I would say your bolt is too small, by a hair. I typically specified them at .480" -0/+0.002. This is not the end of the world if the extractor is shaped correctly. Looking at your pictures, the extractor is already as shaped as I can make it. Please contact Buddy at SBR and request a new bolt, tell him I sent you (he will BBM me to confirm, I'm sure) and I will cover the cost. If that fixes it, please send the old bolt to SBR (ask Buddy for a shipping label, again, I am covering this) Hope that helps Marty |
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Thanks Marty. Bolt on the way.. Quoted:
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Ok.Bolt looks like your Tj bolt includeing the ejector.Thats where i said i thought the ejector had wear on it now i know thats how Marty built it.The bolt face measures .4778" which is larger than case rim but not as large as your bolt face.Now i reinstalled the new extractor spring properly insert case and does have play from side to side but feels like its binding alittle . Turning it to 12:00 it will not fall out even when i shake it as hard as i can.This tells me by the the way yours functions its improper extractor and possable bolt face isnt large enough {compared to both of yours}.Pushing the case out of bolt it feels rough comeing out of extractor and feels rough around case rim not as bad tho as if i fired the round.Case rim measure the same as your . Hey guys, sorry about the absence, just got back 0700 this morning. The extractor spring is installed "upside down" on purpose, this gives the extractor just a little more room to cam should it need it. So I would suggest installing it "wrong", it still gives ample leverage to remove the case. Also, no O-rings, D-rings, etc. From your bolt measurement, I would say your bolt is too small, by a hair. I typically specified them at .480" -0/+0.002. This is not the end of the world if the extractor is shaped correctly. Looking at your pictures, the extractor is already as shaped as I can make it. Please contact Buddy at SBR and request a new bolt, tell him I sent you (he will BBM me to confirm, I'm sure) and I will cover the cost. If that fixes it, please send the old bolt to SBR (ask Buddy for a shipping label, again, I am covering this) Hope that helps Marty |
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Quoted:
Thanks Marty. Bolt on the way.. Quoted:
Quoted:
Ok.Bolt looks like your Tj bolt includeing the ejector.Thats where i said i thought the ejector had wear on it now i know thats how Marty built it.The bolt face measures .4778" which is larger than case rim but not as large as your bolt face.Now i reinstalled the new extractor spring properly insert case and does have play from side to side but feels like its binding alittle . Turning it to 12:00 it will not fall out even when i shake it as hard as i can.This tells me by the the way yours functions its improper extractor and possable bolt face isnt large enough {compared to both of yours}.Pushing the case out of bolt it feels rough comeing out of extractor and feels rough around case rim not as bad tho as if i fired the round.Case rim measure the same as your . Hey guys, sorry about the absence, just got back 0700 this morning. The extractor spring is installed "upside down" on purpose, this gives the extractor just a little more room to cam should it need it. So I would suggest installing it "wrong", it still gives ample leverage to remove the case. Also, no O-rings, D-rings, etc. From your bolt measurement, I would say your bolt is too small, by a hair. I typically specified them at .480" -0/+0.002. This is not the end of the world if the extractor is shaped correctly. Looking at your pictures, the extractor is already as shaped as I can make it. Please contact Buddy at SBR and request a new bolt, tell him I sent you (he will BBM me to confirm, I'm sure) and I will cover the cost. If that fixes it, please send the old bolt to SBR (ask Buddy for a shipping label, again, I am covering this) Hope that helps Marty Recived bolt on wed and range sat all went exellent. No more problems.Bolt face on new bolt was 3 thousands larger than what i had and ejection was no longer weak .Fired 40 rds and not a single extraction issue or ejection problems.Thanks Marty!Old bolt will be sent back to you this week .Thanks Flint and Tony for your help also. |
| I must be dreaming –– this is the way things should be handled here. Pictures and measurements with no BS. I don't own a .458 SOCOM and I had to read this whole thing because it was so well done. Loved the pics and descriptions of how the bolt face is layed out and the way replacing the bolt was handled. |
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