Want a .22lr kit for my AR and am thinking about a SP1 upper and an M261 kit combo. What think ye? Good combo or not? Should I just go with the Ciener and my 6920 upper? Don't plan on doing any competition shooting, but I would like to track my marksmanship progress (or lack thereof). Will mostly use it at a 15yd indoor range, so don't necessarily need it to shoot 0.001 MOA at 100yds.

I have my 261 kit in an early M16 type upper with a 1:12 barrel.   It seems to shoot very well.  I havent tried any serious paperwork with it yet though.

M261 and a 1:12 SP1 upper work very well for me. You might have to test a bunch of ammo to find what it likes best--mine likes Winchester Dynapoints. Your plan sounds like it will work fine for you at 15 yards.

The M-16A1 barrel is a good choice for a .22 lr conversion because the 1\12 twist of the older barrels is much closer to the 1\14 twist that match rimfire rifles use. What ever you decide to do, be prepared to test as many different brands of ammo as you need to to get acceptable accuracy. I had some premimum 22 lr ammo that couldn't group for crap, and some budget stuff that shot really really well.

good news, I already have a sp1 upper and found a M261 kit for good price...
i'm not very familiar with the m261 kit, how does it work exactly ?

Kit slides into the upper in place of the .223 bolt carrier group.  It has a chamber adapter at the front that fits into the .223 chamber and rails running back to the buffer for the bolt to ride on.  Bolt cycles between the adapter and the back of the receiver.  Magazines are inserts that go into a .223 magazine.  

If you're going to "dedicate" the SP1 upper to .22LR then take the gas tube out and turn it upside down so it doesn't blow gas & dirt back into the upper receiver.  The M-261 kit is blowback operated so it doesn't need the tube and that 'll keep it a lot cleaner.


.22LR is 1/16" twist, not 1/14", BTW.