Posted: 8/3/2013 5:51:15 PM EDT
| Hey guys, hoping someone can help me out here. I'm having an issue with my an Evo 12" rail that I installed on my Sig M400, using the factory barrel nut. The past couple of times that I have shot it, the rail itself has slid forward away from the upper. Most recently, over the course of 160 rounds or so, its only a 16th of an inch but still enough to cause concern. I cranked down pretty good on the two screws but it still seems to slid forward. Is there something else I should be doing besides torque the screws down further? Seriously getting frustrated with it. Thanks in advance for your help guys! |
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Quoted: Did you tighten the set screw at the 6 o'clock position by the two tightening screws? |
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Hey guys thanks for stepping in here. you are all correct. First double check to make sure the thermal bushings are installed correctly. The full holes should be at the top next to the gas tube and the half holes at the bottom. If this is done correctly slide the rail back on and clock it properly. Then hold pressure downward on the muzzle end of the HG exaggerating it toward the barrel (this makes sure it aligns perfect with the upper receiver when you tighten it). Tighten each screw evenly until the clamp gap is completely closed (It will feel like a lot but the wrench is little). While you are tightening it you will feel the muzzle end push up against your hand. the rail should now be perfectly in line and tight. Now you can tighten the set screw at the 6 o'clock position. Give me a call anytime if you have any questions. 603-355-3903
Thanks, Andrew Dreher |
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Quoted: Hey guys thanks for stepping in here. you are all correct. First double check to make sure the thermal bushings are installed correctly. The full holes should be at the top next to the gas tube and the half holes at the bottom. If this is done correctly slide the rail back on and clock it properly. Then hold pressure downward on the muzzle end of the HG exaggerating it toward the barrel (this makes sure it aligns perfect with the upper receiver when you tighten it). Tighten each screw evenly until the clamp gap is completely closed (It will feel like a lot but the wrench is little). While you are tightening it you will feel the muzzle end push up against your hand. the rail should now be perfectly in line and tight. Now you can tighten the set screw at the 6 o'clock position. Give me a call anytime if you have any questions. 603-355-3903 Thanks, Andrew Dreher |
| We have not had any issues with any threads pulling out unless the thermal bushings were installed incorrectly. As long as you double check the original install you will be just fine. Also, alternate the tightening of the screws (first front, then back, repeat). If you ever had an issue we would also have your back 100% |
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Quoted:
Hey guys thanks for stepping in here. you are all correct. First double check to make sure the thermal bushings are installed correctly. The full holes should be at the top next to the gas tube and the half holes at the bottom. If this is done correctly slide the rail back on and clock it properly. Then hold pressure downward on the muzzle end of the HG exaggerating it toward the barrel (this makes sure it aligns perfect with the upper receiver when you tighten it). Tighten each screw evenly until the clamp gap is completely closed (It will feel like a lot but the wrench is little). While you are tightening it you will feel the muzzle end push up against your hand. the rail should now be perfectly in line and tight. Now you can tighten the set screw at the 6 o'clock position. Give me a call anytime if you have any questions. 603-355-3903 Thanks, Andrew Dreher Thanks everyone for the advise! I did have the setscrew tightened down, but the gap holding the rail in place wasn't nearly closed, but the bolts felt pretty tight. Going to give that a shot and hopefully it should be good. |
| Hello everybody! My Rainier Arms edition EVO 11" hg is having the same issue. I could not find a set screw on it by the 2 tightening screws. But I did have a noticeable gap. I will loosen the screws, check the thermal bushing and tighten screws evenly until the gap is no longer present. Thanks for the info!!!! |
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We install a TON of these plus we run them on our personal guns. We have never had any slide forward and have never heard of any of the ones we installed sliding, with and with out the set screws. The key is to install the thermal bushings correctly, as Andrew described above. Evos are awesome rails and Samson stands behind their stuff. |
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