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Posted: 2/20/2011 1:51:11 PM EDT
| I've got a Tac Sol .22 M4 upper that everytime I want to change the handguards (I like variety) and depress the delta ring, the delta spring clip dissengages. I don't have any tools per se and the local shop is kind enough to reinstall it for me gratis (about twice a year) but this gets annoying. Am I looking at having to get another clip so this doesn't happen again or is there a quick fix? This is the only upper I have, that this problem happens to. |
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Not the end of the world, but the barrel needs to be pulled, and maybe the delta C clip channel back edge re-lathed on the barrel nut so the edge is clean/square edge). I could be that when the barrel nut C clip channel was lathed, they did not use the correct tool and instead of the both sides of the edges of the channel being cut square, they are cut with the edge walls more of a degree instead. It happens once in a while when the programmer is writing G code for the CNC machine, with the machine not being told to switch out to the correct cutter to produce a squared edge for the side, but instead the machine using some other cutter instead, or just the insert tip of the cutter being worn out/chipped, and instead of producing a shape edge end of cut, leave behind rolled edge instead.
Not sure if you have seen lathe tooling, but when there is a left hand cutter, right hand cutter (edge of the insert flush for that side), a center cutting tool (both sides are angled back) and will not produce a square edge cut, and off degrees of such as well. Basic insert lathe cutters with a center cutter in the middle, a left hand square cutter to the right of the center tool, a right hand square edge cutter to the left hand side of the center tool, and off degree cutters on the ends (if the index of the cutter is set 908 to the stock being turned). Just think of the tools as sticking straight forward, and what side edge on the work piece that the cutter is going to leave. 
If that not the problem, then the C clip replace or installed with the sharp edges towards the receiver if not installed that way. The C clip is a stamp part, and the top edge that was stamped is rounded and needs to be facing the muzzle so the bottom side which will have the shape edges will not slip past the barrel nut delta clip channel if the the retaining edge is square and sharp. |
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I used to work in a machine shop and actually wrote code for CNC work so I'm familiar with what your trying to say. The retaining clip groove edges look sharp so I took a look at the retaining clip and you're right; the clip does have a rounded edge and a sharp edge (I had not considered this prior to your post) and sure enough the rounded edge is facing towards the upper receiver which might be what's allowing the clip to slip outside the retaining groove each time the delta ring is compressed. I learn something everyday!
Quoted:
Not the end of the world, but the barrel needs to be pulled, and maybe the delta C clip channel back edge re-lathed on the barrel nut so the edge is clean/square edge). I could be that when the barrel nut C clip channel was lathed, they did not use the correct tool and instead of the both sides of the edges of the channel being cut square, they are cut with the edge walls more of a degree instead. It happens once in a while when the programmer is writing G code for the CNC machine, with the machine not being told to switch out to the correct cutter to produce a squared edge for the side, but instead the machine using some other cutter instead, or just the insert tip of the cutter being worn out/chipped, and instead of producing a shape edge end of cut, leave behind rolled edge instead. Not sure if you have seen lathe tooling, but when there is a left hand cutter, right hand cutter (edge of the insert flush for that side), a center cutting tool (both sides are angled back) and will not produce a square edge cut, and off degrees of such as well. Basic insert lathe cutters with a center cutter in the middle, a left hand square cutter to the right of the center tool, a right hand square edge cutter to the left hand side of the center tool, and off degree cutters on the ends (if the index of the cutter is set 908 to the stock being turned). Just think of the tools as sticking straight forward, and what side edge on the work piece that the cutter is going to leave. http://www.tools4cheap.net/prodimages/sm14carb.jpg If that not the problem, then the C clip replace or installed with the sharp edges towards the receiver if not installed that way. The C clip is a stamp part, and the top edge that was stamped is rounded and needs to be facing the muzzle so the bottom side which will have the shape edges will not slip past the barrel nut delta clip channel if the the retaining edge is square and sharp. |
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Going to school you again,
The bolt gas rings are also stamp cut, and when installed, you want the sharp ends facing the butt stock ( for semi the same reason, being that the sharp edges will seal better as the rings see pressure, and with the front of the rolled edges forward towards the muzzle. |
| I spoke with Tac Sol today and they said that a year or so ago they had an employee mistakenly build some uppers without checking which direction the delta spring retaining clip was facing which would put my upper right in the middle of that time frame. They told me to send it in for warranty work but I just checked with UPS and the shipping is like $15-20 after buying packaging, etc. It just might be easier and cheaper to have my local gunsmith change it for me. I'll be getting a quote tomorrow. Thanks for all the help! |
| After buying a TacSol .22M4 upper I decided to change out their hand guards with Magpul Moe hand guards and experienced the same problem, but was able to reset the ring myself. When I changed out the guards on my Stag it took 5 min., With the TacSol it took 2 of us over half an hour to do the job..............Ed |
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