I know a lot of guys that have a lot of nice guns that hang on their office walls or they sit in a safe, but they never shoot them. I'm talking VERY expensive setups that they've put together on theory with input from folks, but they've never shot them, or at best, they've shot them at the 25yd indoor range to get the optic "on paper."
You can't set something 80% of the way up, and then declare it "good to go." You need to shoot it and confirm. Zero distance, optic, irons, suppressed and not, with the ammo(s) you plan to use. When you do this, you learn things. One of the things folks quickly learn when they do this is that different guns respond differently to the same inputs.
Here's my story for the week:
I recently put together 2 new AR configurations as pictured below. Both of these are built with top notch components including Geissele triggers and rails, all Colt upper parts including SOCOM barrels (one shortened to 10.3), Nightforce and Aimpoint optics, etc. They look good, and the build lists are impressive, but do they work????
Well, the short one works well. Target is 100yds in an indoor range (I know, cool concept, right? but the lighting still isn't great). Red circled hits are without suppressor, un-circled hits are with suppressor using a 2MOA Aimpoint T1, bipod and rear bag with 64gr Gold Dots. I'll take that!
On to the long one. 5 shots at 100yds outdoors (from a couple weeks ago), 64gr Gold Dots, no suppressor. Grid squares are 1/2", so again, I'll take that all day!
So then I screwed the can on expecting to see the same negligible, if any, shift from the suppressor. I mean, after all I have a thick SOCOM barrel to mitigate droop, etc with the suppressor. WRONG! My rounds wouldn't even hit the IDPA silhouette I was using as a backer. Since this is a recently pinned-welded brake, I assumed it was a mount issue and took the gun back to the shop who did the work (no need to mention their name, but they're a well-known precision rifle shop). 2 hours later they called me to say the muzzle device checks out fine, but they found the problem:
You see, friends, it turns out that hanging a suppressor off even a heavyweight barrel can cause it to move and flex differently and what was enough clearance between gas block and handguard before, no longer is. Apparently having your barrel slap the side of your handguard will have negative impact on your accuracy. So off to home I ran and proceeded to further trim and then refinish the gas block. I then proceeded to the aforementioned 100yd indoor range to confirm correct zero.
100yds unsuppressed with 64gr Gold Dot:
Then I put the suppressor on and was amazed by what I saw:
That is the result of 3 rounds fired aiming at the top target, unmounting and remounting the suppressor, and firing 3 additional rounds aiming at the top target. At least it's repeatable I guess. So, when shooting suppressed with this rifle, I'll dial up 1.6mil (I'll probably make a mark on the turret) and for all other times it'll be zeroed.
Same POA with 1.6mil elevation dialed. I attribute the slighted opened group to the mirage I was seeing off the suppressor at this point.:
Don't assume anything and test all your gear in every condition possible.