Chuffed at my Bloop Tube!

Today was a good day for a range trip.  Sunny and quite calm.  I wanted to spend all my effort on playing with the bloop tube, so all groups are 10 shots of Eley Target.  I know Target isn’t the highest dollar ammo out there, but I’ve tried almost all the Eley and Lapua offerings, and this shoots well in my gun.  Right now in America, we’re in a situation where we take what we can get.  Also, all the groups are off a rest and rabbit ear bag, so my personal wobbling isn’t really much of the equation.  The last detail of note is that I was using 50 Meter targets at 50 yards, so the targets were about 5 meters too close.  One deals with the hand one is given.

First out of the gate, I shoot a couple groups with my standard setup.  This uses the 20mm of sight riser I’ve grown accustomed to.  The groups were “meh” at 18mm and 20mm center-to-center of worst holes.  Like so:

 

I put on the bloop tube.  Everything fitted up nicely.    The aimpoint moved significantly.  This is to be expected as the design kept the sight at the same height from bore center, so it “flattened” out the triangle between the sight line and the bore when it moved forward.  I needed a total of 75 clicks left and 40 clicks up, to get somewhat recentered.  Interestingly, I forgot to tighten the nose screw for the first group. This configuration shot a nice 15mm group.  All groups after this were done with the screw tightened and I did shoot another  15, as well as some 19’s, so I’m assuming no effect on group size unless I do more rigorous testing.  Tightening the screw  did move the aim point up about 5 bullet diameters.

The next test was to remove and replace the tube and see how the point of aim changed.  Zoinks!  Jinkies!  The group moved 70 mm straight to the left.  I didn’t repeat the test any.  I know for certain that if I use this in a match I’ll be doing a thorough re-zeroing.

 

The above 2 targets  are only different in that the tube was removed and replaced.

One other item popped up that I’ll need to address.  The front aperture appears smaller as you move it forward.  This decreases the band of light around the bull.  I'm on my maximum insert now, so I'll need to get my hands on some more discs or a different front sight.  I’m leaning toward the sight because the huge bubble level blocks a lot of the circle that aligns to the rear sight, just a visual thing.

So am I pleased?  Taking 18-20 mm groups down to 15-19 mm groups is nothing to sneeze at.  If fixing the aperture problem can help a bit more, I’d say I’m very pleased.  Or, as the British say, “chuffed as a fart.”