I did some more tinkering trying get the scope mounting more solid. I milled a piece 140mm length of 4mm aluminium alloy plate to a taper and put that between the scope rail and the wooden latch cover of the crossbow. That is much more solid than just shimming one end of the rail.I checked the sighting at 10 yards and confirmed it was pretty good vertically (aiming 3 dots low).
While my better half was out ;-) I set up in the garden, the target boss placed in the doorway of the garage and I put my workmate and a chair near the summer house giving a 20 yard range.
Resting the fore-end on a tightly rolled old duvet and just holding the pistol grip of the crossbow in my right hand and the left cupping the butt of the pistol grip, gave a really steady picture through the scope. I was hoping for a cross hairs on target at 20 yards so that's how I was aiming.
1st shot right height but a couple of inches left. I adjusted the cross hairs on the scope having removed the protective cover. It had an arrow with "L" but does that move the crosshairs left or where the bolt impacts? Anyhow, try it and see.. I turned it 1/4 of a turn left (anticlockwise).
2nd shot, plus 2 others, to see how it grouped... 2" right and all bolts within a finger width of each other... click the adjustment back a bit.
The subsequent shots slowly walked left towards the 10mm black dot I was aiming at as I slowly adjusted the sight.
I cocked the bow for a final shot and though I'd see how it shot off hand (standing with no support).
The image was waving about all over the place compared to how it was when supported, but I relaxed a bit and brought the cross hairs smoothly onto the spot... now theoretically you should squeeze a trigger, well that's fine when you are supported and steady... conversely you don't want to snatch at it... BUT if the trigger is built and set up correctly it should pull in line with the shot and not kick the shot out of line.
(I'm no authority on this sort of thing and have little experience*... it's all just my opinion, so feel fee to disagree, comment etc).
So as I came onto target and popped off the shot... trying to stay relaxed, both eyes open.. it looked good as I saw it hit home through the scope, but it was hard to see exactly amongst the other bolts and holes in the target. A careful look though the scope revealed it had clipped the spot!
I was certainly happy with that, I'll have to try it at 30 and 40 yards sometime and maybe go round a field course, although it is to a great extent just an academic exercise.
Of course it was just one shot...
* I have spent a good deal of time however discussing these things with my brother who is a good shot with shot gun, air rifle and has even shot 303 at Bisley.
Hi Derek. i always follow with interest on your posts and for what it's worth i thought i would comment on your comments on trigger control. Whilst never having shot a crossbow i would think that the theory is exactly the same for air rifles, shotguns, centrefire rifles. i am a qualified BASC shotgun and air rifle coach and shoot my centrefire .243 rifle out to 800yds. You are quite right the trigger should be squeezed and not snatched at. The way i coach clients is to when the thumb on the shooting hand is through the thumbhole of the stock or over the stock grip slowly squeeze the thumb and trigger finger together until the trigger pressure breaks and the shot is sent. Shooting off a rest or freehand still requires good trigger technique to minimise as much as possible the variables in the shot. Snatching at the trigger when shooting can send the shot left if there is any tension in shooting wrist (right handed), and to the right if the shooting wrist is controlled but the trigger finger pulls the shot right...Either way lots of variables are controlled with good trigger technique in the firearms world and i would have thought that transfers to crossbows but happy to defer to experienced crossbow shots if this is not the case...every day is a school day! rgds Adrian
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