AR Sponsor
Posted: 1/2/2011 4:01:17 PM EDT
| I know this question has probably been asked a thousand times, I searched for it and couldn't find an answer. Im not even sure im posting in the correct forum but here goes. Im new to the AR system and I only have experience with optics mounted on bolt guns. So... Say you have two uppers, and both have optics mounted and zeroed. Would you experience a shift in point of impact when switching between the two on the same lower? |
It better not. Otherwise, anytime you set that rifle on different bench, different fence or on any other different support / platform, your POI would also shift. Your lower receiver is basically just that: a platform for your upper to sit on top (well, of course it has the FCG and all that good stuff, too  ).
Now, if you switched uppers on an FAL, that's a totally different story, because the rear sight on an FAL sits on the lower receiver and the front sight sits on the upper. |
|
Everything that has to do with your zero is completely contained in the upper receiver in the AR15 system, so there is no loss of zero switching lowers out. Hypothetically speaking, your upper would still have the same zero if you set it in a vise and used a metal dowel and hammer to fire it.
~Augee |
|
The very nature of the AR platform is such that the upper receiver acts independantly from the lower. Since your optics and the upper is a unit... no problem should be involved with this. I have switched as many as 4 uppers off one lower and never seen any change of impact point due to this. |
AR Sponsor