Does anyone have numbers on how much material needs to be removed from the hooks on a factory lower to fit a semi upper receiver? I was thinking of trying the lower conversion myself.
I use an 11/32" end mill. They are actually a short slot. I plunge through the center, then move the table all the way out of the hooks, then back to 0,0. I have a fixture that holds the lower at an angle so that the Y travel is parallel to the magwell.
There are steel hooks embedded in the plastic. A tiny bit of the metal is machined out as well, maybe just .005"-.010 or so.
Last edited by AviatorDave; 10-20-2017 at 06:31 PM.
@AviatorDave I'm having a UMP clone built from an Omega Gideon Shadow receiver, but we're missing one last piece: the Heckler and Koch G36 / SL8 / USC Left Safety Lever (it's out of stock just about everywhere, atm). I read in the forums that you recut the UMP selector lever so it works with the USC internals. Is that a service you can provide? Can you PM details about that (new member)?
Email me - Dave dot Akins at akinsprecision dot com. My pm's are several hundred over the limit and I haven't taken time to clear old ones out.
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