4" group with a 4" barrel P-10C? No problem.

[Joe L]

I have had one of the original P-10C's since they were first available, but the barrel lockup was a little looser than my other pistols, so I have spent most of my range time with the P-10F and P-10S, mostly the P-10F, since it is just excellent every time I take it out.  A few weeks ago I experimented with a shim to take up some clearance, and that has seemed to work well, but the gun was still inconsistent.  This weekend, I replaced the original Burris FF3 3 moa red dot with an identical new one, and this seemed to have eliminated the inconsistencies I was seeing, even after installing the shim.  I shot a total of 80 rounds today with the P-10C, and I never had a shot that I couldn't explain.  A great day.  Here is a video of the second target of the day.  I spent most of target 1 fine tuning the 100 yard zero after a few rounds at 25 yards.   

https://youtu.be/RWY8_edKqAc

I shot another 30 rounds on target 3 after I pulled this one down, the only difference being I used my go-to Atlanta Arms 115 JHP ammo, with good results and very little zero shift, just not quite as good as target 2 with the IMI ammo.  My eyes were getting tired by that time, and that is all it takes to see a change in the results at 100 yards. 

I couldn't be happier with the pistol, now.  Maybe I can get some similar results with the P-10S next.  We'll see. 

Joe L

[Crawl]

I've found the Burris FF3 to have about the lowest parallax shift of any red dot out there for a pistol. Do you think your first one is defective?

(in my experience, the FF3 is at least as good as EOTech's new EFLX)

[Joe L]

Yes, I think something was loose in the adjustment mechanism.  I've seen the zero shift 6 moa with no external changes between range visits.  I have four of the FF3's, and this one is the only one I've noticed any problems with, from what I remember.  And I only noticed the shift at 100 and 200 yards in steady conditions, so I may not have ever noticed the small shift when plinking at 25 yards off hand, for example. 

I've not noticed the parallax differences between the Burris and Holosun sights I have, but I tend to shoot the pistols from the same position with the dot visible at the same location in the lens almost every range visit so it hasn't been an issue.  My only gripe with the Burris sights is the coarse dot intensity adjustment.  The dot is either too bright or too dim on an overcast day.  The Holosun sights have plenty of intensity adjustment range with small increments. 

Joe

[Crawl]

Agree on all points with the Holosun. I also find it to have low parallax shift except for at the very top of the window, which isn't a problem for me.

This does not include the Holosun K models though. Those have almost all had unacceptable shifts that make the optic unusable for proper zeroing.

[Joe L]

Crawl--I have a K on my P-10S.  I'll see if I can detect the parallax on it.  Maybe I got spoiled on the C models and haven't paid enough attention to my K.  Thanks.
I'll mark a spot on the K lens to place the dot every shot and see if that seems more consistent, unless you have a better idea. 

Joe