| DUGABOY1 |
| (.400 member) |
| 11/06/06 04:03 AM |
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Re: What is causing this - any ideas?
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In reply to:
What puzzles me tho is that the opposite to normal is happening as the powder charge increases. The first group of 2.5 inches had the barrels crossing - the bullets from the right barrel hitting to the left of the bullets of the left barrel. As the powder charge got heavier the group shrank down to the 1" but the barrels are still crossing - not that it is a problem now that the group is down to 1 inch but I am curious to know whats happening - any one else ever had this occur?
GG375, you have no worries! What is happening is what is supossed to happen. you are just about perfect, but if you speed it up just a little more till the individule barrel groups trade places, you will have a perfectly regulated rifle. When perfect, in the 1" composit group the two shots from the right barrel will hit on the right, and the two from the left will hit on the left, all still in the 1" composit group.
place the barrels in a vice, with the sights on the target Aim point. take two emty cases with no primers and chamber them. Now look through the primer flash holes at the target. You will see the RIGHT barrel will be pointing at a spot that is low, and on the LEFT of the aiming point. The LEFT barrel will be pointing to a spot that is low and on the RIGHT of point of aim on the target. This is line of sight through the bore, but not line of bullet flight when fired.
When the RIGHT barrel is fired, it will rise, up, and to the RIGHT , and vice-versa for the left barrel. The time it takes the bullet to get to the point where it exits the muzzle, is called barrel time, and this speed, and recoil arch determens where the bullet hits the target! If slow, it will print high, and WIDE, if fast it will print low, and cross (left on the right, and right on the left) the shooting wide is proper, if both barrels are hitting close enough to form a tight composit group, without crossing! You need to speed up just a little to have it perfect!
What you are experiencing is proper. As the speed goes up, the bullets leave the barrels sooner in the recoil arch, so if the right is hitting on the left, and the left is hitting on the right, the speed needs to go UP till they don't not cross, but each barrel shoot it's own group right beside the other barrel, with the right on the right, and the left on the left on the target. But still close enough together to make a tight composit group. Then the rifle will shoot paralel till it comes to Earth, and never cross! It is a falicy that all double rifles cross at some point! They don't if they are loaded with loads that match the regulation.
