More of a PSA than anything. Might be obvious to some.
So I splurged on an 11.5" Virtus in 5.56 and since I already have a 10.5" ACR and I form 1'd the lower, I thought well hell, I'll buy the 6.75" 300 blk kit from the Sig Store and have some fun with it. Of course, none of my cans fit in the stock HG, so new HG on order. Got a 6" from MWI and it looks fantasic. So I thought well, I'll just dial my XTRII 1-5 in a G mount and note my zeros so I can run the same optic... Not even close. Not close enough to zero at 50 yards within a full rotation of the windage nor elevation knobs. So now I throw on a QD red dot (510c) for the .300 blk upper.
Was at my shooting spot yesterday and realized that I now had the 11.5" Virtus, a 1/2" wrench to remove the G mount, another barrel setup, another can, another HG, another optic, and Torx wrench to remove the barrel, etc... on top of all the usual mags, belts, staple guns, etc.
I say all that to say this: By the time I was done buying shit to be able to swap... I should have just bought a 2nd complete upper or a Hybrid in 300 for not much more. I was really disappointed that I wasn't able to use one optic and the 10" SD handguard. Expensive lesson.
Am I the only one whose barrels are feet apart @ 50 yards? 220gr. S&B subs. And for the obvious question, the 300 was 18" higher and 4-6" left of 556 POI. Also the 6.75 will only run on '+' with subs and Sandman-L