The weather fairies looking upon today favorably, I was able to make it the range and try out the Armalite AR-180b with it's new StormWerkz scope mount base.
I'd like to start by making something clear. I'm not proud of my shooting today. With this rifle, using metallic sights and generic Federal ammunition I have regularly shot 100 yard groups under two inches.
(Excuse mode on)
That said, I was shooting plinker ammo today thrown together with mixed components, and doing so in weather cold enough that I was forced to wear gloves or lose feeling in my fingers altogether. The twenty mile an hour variable breeze did not help much either.
(Excuse mode off)
One major goal for the day was getting it sighted in properly on the paper an inch or so high at 100 yards giving me a reliable 200 yard dead on shooter. The other project was to explore the function of the mount itself. Since it's an easy on / easy off mount, I was curious what removing and reinstalling the optics would do to the rifles zero.
Towards that end I did a fairly simple test. Once sighted in and on the paper, I fired a ten round group from the bench taking care to follow the best procedure I know. Doing the same with my varmint rifle yields steady half inch groups at 100 yards.
After firing the control group, I fired another ten round group using exactly the same procedure with one large difference. In between each round (and before the first one) I dismounted the scope and reinstalled it by using the scope base. The base is spring loaded and dovetailed to the rifle, as described in a previous writing.
It should be noted that after firing even one round the scope and base is wedged quite tightly on the rifle's bracket. It requires a rather hard smack with the palm of the hand to dislodge it. I was concerned that this constituted mistreatment of the optics and fired another group when I was finished to make sure I wasn't damaging the scope. There is clearly no danger of the scope coming off during normal use.
The results are pretty clear. The control group measures right around two inches and is centered one inch to the right of the bull. The group fired while removing the scope after every round is about four inches and slightly over two inches to the right of the bull.
As mentioned, another group was fired after the testing to check the scope once again. It was shot with a more accurate load using a different bullet, but not the rifles favorite. As shown, it centered nicely just above the bullseye and measures just under two inches.
My conclusion: I need to test more, especially when I am not shivering. I suspect the mount settles in after a few shots and remains rock steady after that. I still intend to mount a holographic sight on this base, and of course I'll have to play some more once that's done.
Right now I see that removing and installing the optics with the base mount clearly changes the zero a recognizable amount. I will explore techniques for minimizing that tendency. Perhaps a settling smack with the hand after mounting the base will help.
I still like this mount set up, a lot, and I still intend to get at least one more.