I guess stance and hold is pretty important to guage the grouping. My IHP did not do well until I crossed the 300-400 mark, after which, I started improving on the grouping.
I check on the grouping of all my airguns in the following way:
1. Fixed target, at height of the how I place/hold the gun.
2. Preferably 'rest' the front of the rifle on a padding (I use hardened foam).
3. Hold the gun at the same place for all teh shots, with the same hold and pressure. (Same with cheek rest and pressure on butt). I prefer to sit down on a chair, and have the gun rest on a steady table.
4. Use only pellets that fit in correctly (guaged to as well as the user can judge). I dont use the pellet if it is very smooth or very tight fit.
5. Repeat the H.A.T (Holding, Aiming, Trigger Operation) methood exactly (or close) for every shot.
6. Check groupings for 5 and 10 shots, two or three times.
The .177 IHP improved grouping in about 300-400 shots.
The .177 IHP Pistol came in a used condition. So no comments on this.
The .177 HW77K has just about crossed around 300 shots, and am yet to find substancial difference, but anyday beats the IHP (of course
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)
What I aim to find out is:
1. Variation (for the better) of grouping.
2. Variation of recoil - especially the position of the aim after the shot has been fired.
3. Trigger operation.
It would be hard to simulate the exact strategy for all guns you try, but keep close in ensuring that human body inconsistencies (change in grip, hold, aim, cheek pressure, stance etc) dont reflect on the grouping, which may hamper your judgement.
Looking forward to the 10K german make
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