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 P9 rail (not extended) - rail-mounted front sight work okay with receiver-mounted rear sight?
engineer2001  [Team Member]
4/23/2009 9:21:48 PM EDT
I just bought a Predator P9 rail - the P9, not the X model that covers the entire upper receiver. I love the P4 rail I bought last year, and I wanted one for my 9mm build. However, on this one, I want to use a rail-mounted front sight. My 9mm build has no gas block at all, so there's no way to use a front sight unless I mount it on the top rail.

I want to replace the MI rail in this pic with the Predator and not have to use the risers under the red dot:

Will the rail-height front sights like the Midwest Industries flip-up sights work on the Predator top rail and zero like it should, since it is ~1/2" higher than the receiver? The rear sight on the non-extended rails goes on the last notch of the receiver behind the Predator rail. I know from my P4-railed 5.56 build that the ARMS 40A2 sight like I have fits in that last slot behind the rail fine, but will it zero with the elevated front sight on the Predator's top rail?

Thanks for any info you can provide!

EDIT: Looking at what Google images turns up for "POF upper", it seems they used to have a railed sight block that the POF hooded front sight sat on with these non-extended rail systems behind them. Now, they seem to be using the extended rails on all the new upper halves, with the hooded POF sight on the top rail. Does this mean a rail-mount front sight wouldn't work with the receiver-mount rear sight, and they had to change the design to cover that rear sight area too? My Predator P4 is on a 5.56 upper with a standard fixed front sight. I may have to put this P9 on a middy build with the same.
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