Ya,the back portion will be a breeze with the reamer tool I'm having made.What I mean is the cylinders will not even slide in up to the thickened back part of the cylinders.you would think they should slide in for the first 5" till they hit that point you need to mill out.After lapping with a 1" steel dowel for about 15 minutes ,the blue slides in to the ridge,the gold slides about half way and the two red ones I have to twist them in.So the cylinders vary in diameter a few thou .Just wondering if anyone else has run into this before.4 RS uppers ,4 cylinders what are the odds I'm the only one
.Just saying I haven't read anything about this. That's all. lapping is working.
The Colt upper with the bigger front take down pin hole,I have a bushing with an off set hole.I plan on loctiteing it in perm, when and if I use that upper.I'm leaning more to the flat top armalite for now.But am planing on spare complete uppers later
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