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Posted: 7/14/2009 2:00:16 PM EDT
| I am building a lefty AR for a friend using a DPMS lefty upper receiver. Will a Stag lefty bolt work in this receiver...or do I need to use the matching DPMS bolt? I am using a standard right handed carrier, but I wasn't sure if the bolts are interchangeable. Thanks. |
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No the Stag uses a different bolt than DPMS because of the LH carrier that Stag uses. The DPMS is a RH bolt that has the cam pin hole changed to allow it to only be inserted for LH ejection. A regular RH bolt can be modified to work in the DPMS. I know because I have done it.
Obviously there is or was a difference between my upper and the one that Quick Straw has, so don't try to modify a RH bolt for a LH upper! My apologies to all for what turned out to be bad technical advice. So if you have a LH upper, use a LH bolt. Stag uses a special LH carrier and upper that are almost a mirror image of a RH upper (the ejection port door is upside down) so the carriers are not interchangeable with RH carriers(the bolt cam cut is also the opposite as where the spent gas tube exhaust holes in the bolt carrier)! However the good news is the Stag LH bolt will work in a RH carrier for the DPMS upper...that is unless they have changed something on that also. Check the link below for images of a RH and LH carrier with LH Stag bolt installed. http://s659.photobucket.com/albums/uu312/LynC2/AR15%20bolt%20carriers/ Edited to avoid any possible issues, I hope! |
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No the Stag uses a different bolt than DPMS because of the LH carrier that Stag uses. The DPMS is a RH bolt that has the cam pin hole changed to allow it to only be inserted for LH ejection. A regular RH bolt can be modified to work in the DPMS. I know because I have done it.
Thanks for the response....I have an extra RH bolt. How do you modify it work with the DPMS lefty upper? |
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Quoted:
No the Stag uses a different bolt than DPMS because of the LH carrier that Stag uses. The DPMS is a RH bolt that has the cam pin hole changed to allow it to only be inserted for LH ejection. A regular RH bolt can be modified to work in the DPMS. I know because I have done it.[/quote]
Thanks for the response....I have an extra RH bolt. How do you modify it work with the DPMS lefty upper? The cam pin hole in the bolt is reduced on the opposite side for the LH. One needs to open up the hole for the cam pin to fit and don't remove any more metal than necessary. Be warned that after modification it will be possible to install it backwards in either a RH or LH upper! Just make sure the extractor points out the ejection port and you're GTG. 
Correction: the LH Stag uses a different carrier than DPMS. The DPMS uses a RH carrier and LH bolt to allow it to only be inserted for LH ejection. Edit to correct data. |
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The cam pin hole in the bolt is reduced on the opposite side for the LH. One needs to open up the hole for the cam pin to fit and don't remove any more metal than necessary. Be warned that after modification it will be possible to install it backwards in either a RH or LH upper! Just make sure the extractor points out the ejection port and you're GTG.
Awesome....I'll give it a try. Thanks. |
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Quoted:
Quoted:
No the Stag uses a different bolt than DPMS because of the LH carrier that Stag uses. The DPMS is a RH bolt that has the cam pin hole changed to allow it to only be inserted for LH ejection. A regular RH bolt can be modified to work in the DPMS. I know because I have done it.
Thanks for the response....I have an extra RH bolt. How do you modify it work with the DPMS lefty upper? The cam pin hole in the bolt is reduced on the opposite side for the LH. One needs to open up the hole for the cam pin to fit and don't remove any more metal than necessary. Be warned that after modification it will be possible to install it backwards in either a RH or LH upper! Just make sure the extractor points out the ejection port and you're GTG.
What carrier are you using? |
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Left handed uppers require a left handed upper, bolt and carrier. yep TWIMC The Stag LH uses a different bolt and carrier than DPMS because it is a mirror copy of the system and the rotation of the bolt is opposite of the RH systems. The DPMS uses a RH carrier and a modified RH bolt that only allows it to be inserted for LH ejection. They are not interchangable! |
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Quoted:
Quoted:
Quoted:
No the Stag uses a different bolt than DPMS because of the LH carrier that Stag uses. The DPMS is a RH bolt that has the cam pin hole changed to allow it to only be inserted for LH ejection. A regular RH bolt can be modified to work in the DPMS. I know because I have done it.
Thanks for the response....I have an extra RH bolt. How do you modify it work with the DPMS lefty upper? The cam pin hole in the bolt is reduced on the opposite side for the LH. One needs to open up the hole for the cam pin to fit and don't remove any more metal than necessary. Be warned that after modification it will be possible to install it backwards in either a RH or LH upper! Just make sure the extractor points out the ejection port and you're GTG.
What carrier are you using? It is not a mirror image like the Stag. In the Stag L everything is backwards. IRRC the DPMS LH system just uses a regular carrier with a bolt 180 deg off. The LH bolt still rotates in the same direction as the RH one would but the ejector is in the proper position to flip the shell out the ejection port on the Left side of the rifle. ETA: If you don't believe me look at where the recess for the cam pin head is on a DPMS LH upper. The hump on the outside of the reciever is in the same location. They didn't invest a whole lot in tooling up for the Lefty Models. One of the older Paladin Press books had a suggestion about doing exactly this for a LH AR it was either: AR-15/M16 SUPER SYSTEMS or THE COMPLETE AR-15/M16 SOURCEBOOK |
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Quoted:
Quoted:
Quoted:
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No the Stag uses a different carrier than DPMS because of a different LH upper that Stag uses. The DPMS is a LH bolt that has the cam pin hole changed to allow it to only be inserted for LH ejection. A regular RH bolt can't be modified to work in the DPMS.
Thanks for the response....I have an extra RH bolt. How do you modify it work with the DPMS lefty upper? The cam pin hole in the bolt is reduced on the opposite side for the LH. One needs to open up the hole for the cam pin to fit and don't remove any more metal than necessary. Be warned that after modification it will be possible to install it backwards in either a RH or LH upper! Just make sure the extractor points out the ejection port and you're GTG. Edited correct information What carrier are you using? It is not a mirror image like the Stag. In the Stag L everything is backwards. IRRC the DPMS LH system just uses a regular carrier with a bolt 180 deg off. The LH bolt still rotates in the same direction as the RH one would but the ejector is in the proper position to flip the shell out the ejection port on the Left side of the rifle. ETA: If you don't believe me look at where the recess for the cam pin head is on a DPMS LH upper. The hump on the outside of the reciever is in the same location. They didn't invest a whole lot in tooling up for the Lefty Models. One of the older Paladin Press books had a suggestion about doing exactly this for a LH AR it was either: AR-15/M16 SUPER SYSTEMS or THE COMPLETE AR-15/M16 SOURCEBOOK Nope, they just cut the ejection port on the left side and changed the cam pin hole in the bolt so it can only be installed for LH ejection. Kind of half ass IMO. The bolt carrier then tries to exhaust into the upper RH side of the reciever instead of through the ejection port. 
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The cam pin hole in the bolt is reduced on the opposite side for the LH. One needs to open up the hole for the cam pin to fit and don't remove any more metal than necessary. Be warned that after modification it will be possible to install it backwards in either a RH or LH upper! Just make sure the extractor points out the ejection port and you're GTG.
I tried this last night...but when I rotated the bolt 180 degrees and inserted the cam pin, the ejector did not line up with the ejection port. The ejector is pointed slightly downward preventing the rounds from being ejected. Am I missing something? How did you get this to work? |
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I know it worked in mine; I used it as a match rifle for years for NRA Hi-power competition. Perhaps there were some changes between when my DPMS upper was made and yours. I am aware it is pointing downward as opposed to being at an upward ejection pattern, but it did work in my case. I am unable to put up a picture of my rifle as I sold it after getting the Stag LH uppers; however I don't doubt you're having a problem. I'll put my money where my mouth is and swap you a new bolt (if I can find one!) for your modified one if you wish since you followed my advice and are having issues.
See 3rd post for update! |
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I know it worked in mine; I used it as a match rifle for years for NRA Hi-power competition. Perhaps there were some changes between when my DPMS upper was made and yours. I am aware it is pointing downward as opposed to being at an upward ejection pattern, but it did work in my case. I am unable to put up a picture of my rifle as I sold it after getting the Stag LH uppers; however I don't doubt you're having a problem. I'll put my money where my mouth is and swap you a new bolt (if I can find one!) for your modified one if you wish since you followed my advice and are having issues.
I'd glad to trade my modified RH bolt for a DPMS lefty bolt. Do you have one? |
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Quoted:
The cam pin hole in the bolt is reduced on the opposite side for the LH. One needs to open up the hole for the cam pin to fit and don't remove any more metal than necessary. Be warned that after modification it will be possible to install it backwards in either a RH or LH upper! Just make sure the extractor points out the ejection port and you're GTG.
I tried this last night...but when I rotated the bolt 180 degrees and inserted the cam pin, the ejector did not line up with the ejection port. The ejector is pointed slightly downward preventing the rounds from being ejected. Am I missing something? How did you get this to work? That is what I was thinking. |
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Quoted:
I know it worked in mine; I used it as a match rifle for years for NRA Hi-power competition. Perhaps there were some changes between when my DPMS upper was made and yours. I am aware it is pointing downward as opposed to being at an upward ejection pattern, but it did work in my case. I am unable to put up a picture of my rifle as I sold it after getting the Stag LH uppers; however I don't doubt you're having a problem. I'll put my money where my mouth is and swap you a new bolt (if I can find one!) for your modified one if you wish since you followed my advice and are having issues.
I'd glad to trade my modified RH bolt for a DPMS lefty bolt. Do you have one? I'm afraid not and DPMS does'nt either. I might be able to find a RH for you someplace though. |
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Obviously there is or was a difference between my upper and the one that Quick Straw has, so don't try to modify a RH bolt for a LH upper! My apologies to all for what turned out to be bad technical advice.
So if you have a LH upper, use a LH bolt. Stag uses a special LH carrier and upper that are almost a mirror image of a RH upper (the ejection port door is upside down) so the carriers are not interchangeable with RH carriers(the bolt cam cut is also the opposite as where the spent gas tube exhaust holes in the bolt carrier)! However the good news is the Stag LH bolt will work in a RH carrier for the DPMS upper...that is unless they have changed something on that also. Check the link below for images of a RH and LH carrier with LH Stag bolt installed. http://s659.photobucket.com/albums/uu312/LynC2/AR15%20bolt%20carriers/ Edited to avoid any possible issues, I hope! Thanks for all your help....this is good info, and the pics are exactly what I needed. I will order a LH Stag bolt to use, since they are readily available. No worries about my modified bolt...I'll keep it as a spare. BADAZZAR15....will you sell me just a Stag LH bolt, without the carrier? edit....I just ordered one from Stag, ships in 1 week. |
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