I've seen many threads on this topic and all of them discuss the theory, but I have not seen one with shooting results. So I thought since I have all the stuff, why dont I just go give it a try.
This post is not just about accu wedge.
I have the following items:
Accu wedge: $4.95 USD
Griffin Armament over sized pins: $25 CAD
Brownells reciever shims $23.99 USD
I installed all of these. If accu wedge does improve accuracy, then having all 3 of these installed should be much more effective than just the wedge.
So, now onto the other stuff.
Rifle: HK MR223A3 14.5 inch
Optic: Minox ZP5 5-25
Ammo: FGMM 223, 77
Shooter: Me. I don't compete in any way. Never taken any rifle classes. Less than 10,000 rounds down the pipe in my whole life. Visit range 1-2 times per month.
Setup: Rifle resting on wooden block in front, rice bag in the rear. Here is picture:
Shooting done from prone at target 100 yards away. I bought a box of 20 rounds. Wasted 2 rounds, so I had enough ammo to shoot 2 5 round groups and 2 4 round groups. I installed the shim, wedge, and pins at home. When I arrived at the range, I first shot a 5 round group and then a 4 round group, with all the stuff installed:
Then I disassembled the rifle, took out the wedge, installed the stock pin, removed the shim and shot another group of 5 and 4:
As you guys can see, there is a difference. The 2 groups with the devices are better than the 2 groups with the stock rifle, thats a fact.
Now, could this be within the margin of error of the weather condition, rifle, optic, and me? 100%. So take a look and think about what you will be doing with your rifle. I took off the 5-25 optic right after this test and dont intend on installing it back onto this rifle anymore. For my purposes, I will not notice this difference again as I will not be using this high power optic and this expensive ammo for my regular shooting. And the cost to me is not simply $4. If I can travel back in time, I would of stopped myself from buying these things.
But maybe some people will think that improvement is worth it for their intended purpose, in which case I would say dont just get the wedge, get all the receiver tightening devices that you can get. Or just epoxy them together.