I just got a new upper (a Vltor VIS), and the front push-pin hole seems to be tight or misaligned. I could not push it in with finger pressure, and had to tap in place with a small mallet. Like wise pushing it out; I had to use a punch and mallet. I tried the upper out on two different lowers and the fit was the same. Is this within the limit of acceptability? Will it hurt the lower any with such a tight fit?
fwiw i’m new to ar platform …
my vis upper came from Grant and Stag lower from local gunshop.
Front pin was easy on first try but rear takedown needed a little help from a mallet.
After a few times rear pin now easily pushes out with finger or nose of a round.
Again i’m a newb so I have nothing else to compare to.
Ed
Same here as NY45. Easy on the pivot in front but tight in the rear.
Could this be a misalignment issue? I thought these CNC billet jobs were to be super in-spec. I have another VIS I bought last year and had no such problems with it.
I would think that a complete upper/lower package would be spot on when it comes to fit. You are correct as they are really precise in spec. However I’m running a different lower than the Vltor lower. Is your rifle a full Vltor assembly?
Are you sure its the Upper, and not:
Out of spec detent, or detent spring?
I was swapping uppers and lowers around, and it is just this VIS that hangs up at the front pushpin. The other VIS goes on no problem, as do my other uppers- in fact I can push the front pin out with only finger pressure on the older VIS.
I recently built a precision AR using a RRA 20" bull barrel upper. The upper fits very tight on all of my AR lowers. The front pin goes in fine, but the rear pin must be tapped in/out with a mallet.
In this case, I don’t really mind, as I believe the firm receiver/receiver fit makes for a better precision platform. However, although it’s mainly a range/bench gun, it concerns me that if I have a malfunction which requires me to pop the pins, I wouldn’t be able to do it quickly without tools.
On a defensive carbine, I don’t think a firm fit is a good thing…
I’ve the same “problem” when swapping various uppers and lowers. I am in agreement with the previous poster; precision bench gun, no problem, defensive/tactical weapon, I’d prefer a looser fit. Figure out what is important to you.