Bullet Drop
#1
Bullet Drop
Here is my set up, CVA Kodiak with a Leupold 2-7x33 scope shooting 2 pellets of Tripple 7 (100grs) pushing the 350gr hornady FPB,and my CVA has a 28in barrel..I've been shooting the FPB since they came out and absolutly love them,my Kodiak will put them in 1 to 1.5inche groups all day long at 100yds.I love the bullet,but have never felt the need to shoot past 100yds..Well I recently got on a new hunting lease and a longer shot can be expected,its fairly open..So im wanting to strech my shot a little bit..How much drop could I expect from a 100yd zero to 150yds? Im gonna try it at 150 to see for myself,but I would like to know a general idea of how much it will drop..Do you think I otta maybe try 150grs of powder? I've always heard that 150grs of powder is really a waste.
#4
Boone & Crockett
Join Date: Apr 2007
Location: River Ridge, LA (Suburb of New Orleans)
Posts: 10,917
That load should be giving you something around 1650 fps brushbustin, which is plenty of energy out past 200 yards.
Trajectory is the issue. With a 100 yard zero you will be about an inch high at 50 and 75 yards and five or six inches below point of aim at 150 yards (fifteen inches low at 200). You might consider adjusting your impact point to something like and inch and a half high at 100. That should put you about two inches high at 50 and 75 and only three inches low at 150. It will still be about six inches low at 175 and almost a foot low at 200.
None of that is a problem if you have a good feel for the load's trajectory and a decent estimate of the range you're shooting.
Trajectory is the issue. With a 100 yard zero you will be about an inch high at 50 and 75 yards and five or six inches below point of aim at 150 yards (fifteen inches low at 200). You might consider adjusting your impact point to something like and inch and a half high at 100. That should put you about two inches high at 50 and 75 and only three inches low at 150. It will still be about six inches low at 175 and almost a foot low at 200.
None of that is a problem if you have a good feel for the load's trajectory and a decent estimate of the range you're shooting.
#5
Nontypical Buck
Join Date: Aug 2008
Location: Rapid City, South Dakota
Posts: 3,732
In order to make ballistic calculation, one needs to know the muzzle velocity. I don't know what your muzzle velocity is, but will guess it is around 1750 feet per second. Calling this the muzzle velocity results in the following calculation.
Another option is to sight your rifle so that the bullet impacts 3" high at 100 yard. This allows for hits at longer range with a center of chest hold. Here is a calculation for that situation.
Sighting in 3" high at 100 yard results in a dead deer with a center of chest hold out to about 175 yard. Of course if your bullet does not start at 1750 fps, but instead is slower, the bullet will not fly as flat as the calculations predict.
Another option is to sight your rifle so that the bullet impacts 3" high at 100 yard. This allows for hits at longer range with a center of chest hold. Here is a calculation for that situation.
Sighting in 3" high at 100 yard results in a dead deer with a center of chest hold out to about 175 yard. Of course if your bullet does not start at 1750 fps, but instead is slower, the bullet will not fly as flat as the calculations predict.
#6
brushbustin
One thing i would remind you is that really are not shooting a 100 grains of T7 since you are shooting pellets. Your load would be close to the equivelent of 100 grain of true BP (other than Swiss it is closer to T7 than any other BP) or Pyrodex. The load would be equivelent of 85 grains of T7.
I think that Semi's estimate of 1600 fps second to be very close to your actual velocity. As an example I shoot a 400 grain Bull Shop conical with 100 grains of loose T7-3f and the average velocity runs right at 1550 fps.
If you are or might sight your rifle in again I would suggest you follow Ron's thoughts and sight the gun it @ 2.5" high at 100 that will easily cover you at 150 to 175.
There still is no replacing making the shots on a target to verify your POI.
One thing i would remind you is that really are not shooting a 100 grains of T7 since you are shooting pellets. Your load would be close to the equivelent of 100 grain of true BP (other than Swiss it is closer to T7 than any other BP) or Pyrodex. The load would be equivelent of 85 grains of T7.
I think that Semi's estimate of 1600 fps second to be very close to your actual velocity. As an example I shoot a 400 grain Bull Shop conical with 100 grains of loose T7-3f and the average velocity runs right at 1550 fps.
If you are or might sight your rifle in again I would suggest you follow Ron's thoughts and sight the gun it @ 2.5" high at 100 that will easily cover you at 150 to 175.
There still is no replacing making the shots on a target to verify your POI.
Last edited by sabotloader; 10-27-2010 at 08:55 AM.
#8
#9
Nontypical Buck
Join Date: Aug 2006
Location: Rivesville, WV
Posts: 3,192
Point Blank trajectory is normally figured at 5" in a big game rifle, and 2.5" for a varmint round.
You are shooting your rifle at big game. So a 5" point blank range would work just fine for you.
Getting out to 150 with a 5" point blank range is easy. You should be able to do it with a 3" PB range. So set your rifle 3" high at 100 yards then keep moving your target backwards until you are 3" low. That will give your max distance.
Personally I do not like charts. Rarely are they correct. Too many other variable involved. One being the height of the scope off the bore. Only real way to know is to shoot it.
But IMO 3" will work great. And should get you just past 150 yards. Tom.
You are shooting your rifle at big game. So a 5" point blank range would work just fine for you.
Getting out to 150 with a 5" point blank range is easy. You should be able to do it with a 3" PB range. So set your rifle 3" high at 100 yards then keep moving your target backwards until you are 3" low. That will give your max distance.
Personally I do not like charts. Rarely are they correct. Too many other variable involved. One being the height of the scope off the bore. Only real way to know is to shoot it.
But IMO 3" will work great. And should get you just past 150 yards. Tom.