MkIII 22/45 Upper to MKIII lower

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Simon6101
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MkIII 22/45 Upper to MKIII lower

Post by Simon6101 » Thu Sep 10, 2009 9:26 pm

I have a friend that wants to install a MKIII 22/45 upper on a MKIII metal lower. We can not get the upper on the frame at all. Can someone post pics of what needs to be done to make it fit. Thanks

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Bullseye
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Post by Bullseye » Thu Sep 10, 2009 11:40 pm

The front underside of the 22/45 receiver has been peened at the factory to keep the receiver tight on the polymer frame. You can see this if you remove the receiver, flip it over and look at the front lug area.

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What you can do is swage out the dent to allow the front lug to seat. Some folks have been successful with grinding out some of the material inside the receiver tube lug recess for the front mounting lug. Either way will work but once the receiver is modified it will not sit tightly on a polymer frame again.

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Simon6101
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Thank you

Post by Simon6101 » Fri Sep 11, 2009 8:29 am

I thought that was the area everyone was talking about but needed to be sure. Bullseye comes through again

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