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nottelybill
November 21, 2008, 01:24 PM
the only place I have that i can get 40 yds with a back-up is where the target will be 15 ft. below the bench. I have no idea how to compensate when patterning my shotgun for that difference in the level. also what difference would it make with #4,#5, and #6 shot if any. I know it will not be an exact answer but any help is better than me guessing.

Brad Clodfelter
November 21, 2008, 01:47 PM
You gun barrel won't notice the difference in the 15ft difference to make it a concern.

Just shoot it and find what loads work well.

The shot size to me matters more to what the game you are trying to hunt. But my all means make sure the one you choose, patterns well.

I like using #4's on turkey, but others like #6's or maybe even 5's. It's just a matter of preference and what you and your gun seem to like.

BigJimP
November 21, 2008, 02:39 PM
Rather than shoot 15 feet downhill at 40 yards - what condition do you have say at 20 yards ? Can you get some indication of your point of impact at that range / then move back to 25 yards, 30 yards, 35 and 40 ..

Balistically, I don't think the shot column will rise that much as it leaves the barrel ( but I'm not positive either ) - so I don't think you're going to see a big difference in the point of impact, using birdshot, shooting downhill.

When you pattern a gun / first of all you're looking for the point of impact ( and I usually use a Full choke ) to make sure the gun hits where I'm looking. I would test it at 20, 25, 30 yards ... and see if it varies at all.

Secondly, you may be patterning how effective a choke is at 40 yards ( say a Modified choke ) so you draw a 30" circle around the point of impact / or you may be checking certain loads to see if there are any holes in the pattern that would let a target thru unharmed ( a reasonably dense 30" pattern is usually ideal at the respective kill range - so you vary the choke accordingly). For pattern / load testing I would suggest a Cyl choke at 20 yards, IC at 25 and 30yards, Mod at 35-40 and see how it looks.

Let us know what you find out about shooting downhill - we might all learn something.

zippy13
November 21, 2008, 03:10 PM
Consider competition shotguns: Most are patterned on the level, but the targets are typically higher, but sometimes lower. Slope doping is routine for snipers and long range riflemen but foreign to the majority of shotgunners. If you're in to slugs and have an adjustable sight, you might want to experiment for your own satisfaction.
+1 on BigJimP's recommended procedures.
Three statisticians purchase identical hunting rifles and take a newbies marksmanship course. After the book study, they head to the range for live fire training. The coach reminds them of the lesson on zeroing and calls the first statistician to the the line.
The fellow tries to remember everything he's recently learned and squeezes off his first string. The coach compliments him on the size of the group and says, "You're 6-inches to the left and 2-inches low. Make your adjustments, as you learned in class, and fire another string." The shooter complies, and his second group is dead center.
Next, the second statistician shoots his initial string and the coach announces, "You're 6-inches to the right and 2-inches high..." The second guy adjusts, fires, and his second group is dead center, too.
Then, the coach beckons the third statistician to the line; but, the guy replies, "No thanks, Coach. Statistically it's already dead on."

nottelybill
November 21, 2008, 05:43 PM
I have a good knowledge of sigthing in rifles. I was trying to get an idea what would happen with a shotgun, if I had to sight in under those conditions. I think I will go point blank with what i have and adjust my red dot accordingly. I am shooting a .665 choke and I usually use #5"s.

BigJimP
November 21, 2008, 07:03 PM
A red dot on a shotgun / I'm missing something obviously ...

nottelybill
November 21, 2008, 08:35 PM
I have a 20 guage that has been tapped and drilled for a picatinny rail and a red dot sight. It is a good aid since I have lost sight in my left eye. Just put the dot on target and pull the trigger. But I would have to zero or pattern my gun regardless of the sigthing mechcanisum.