in2anity wrote:Your groups aren't terrible - about standard for a No1. Probs around 4moa? (which was spec). Patterning looks pretty ok. Time and again i witness the POI change over a couple of stages as the barrel heats, particularly noticeable at distance. Not sure about the AF mount - I've not had a lot of luck with them myself. A few very experienced shooters have told me they won't do much better than "minute of man" at 300m, but I'm not convinced it's the mount, rather the hot barrel.
Yes, I was surprised when I measured them to find they were tighter than they looked. Excluding the fliers I called, the groups with the Driver and Hornady are around 32mm, or just over two-minutes, the 6rd Bertram group is only 43mm. The 4rd Hornady group is 28mm.
The first three groups were fired resting across my jacket folded across a log. But I couldn't get my shoulder and wrist into anything resembling a comfortable position so the butt was not against my arm or shoulder, I had my left hand supporting the toe of the butt and it was free recoiling.
I went and got a couple more logs from the pile to make an adjustable pyramid, then spent fifteen minutes trying to determine the height I found most comfortable. If I get my shoulder too high then I can't roll my wrist enough to feel the trigger pull, if I get too low it pulls my palm away from the stock. Prone unsupported is much easier as I just allow my broken body to fall into its own comfortable position
The last three groups were shot rested directly on a log with my left hand wrapped around my right bicep and the toe rested in the V of my thumb. It's an SMLE in .303, not a precision rifle. A better load will group maybe two-inches at 100m, a poor one will group maybe three or four inches, which should be obvious without requiring a Lead Sled
If I remember I could take the MTM shooting rest up for the final group test.
I'm not impressed with the Arctic Fox mount either. Replacing the screws has made it fairly usable for load development, but is not something a customer should have to worry about. It has now held zero over 42rds, which is long enough for a deer shooter I guess, but I don't have enough confidence in it to ever take it hunting - I would have more confidence in the iron sights - even with the SMLE that offers you three front sights to choose from
The mount is held in place by jamming it longitudinally between two unmachined cast surfaces of the receiver, so it's never going to be a precision fit. If either of those surfaces has the slightest negative slope the screws are going to walk up the slope. Even a slight positive slope should lock it in nicely, but that generally requires filing such a slope into the surfaces, which defeats the entire purpose of spending $200 on a mount to avoid damaging the rifle. I did check the screws again and got another few degrees into them, but perhaps after a few hundred rounds it might finally settle in, who knows. I only need it for a few more groups. I could try it on the second SMLE but that would entail removing the PH aperture sight.