Kablam
12-30-2001, 10:36 PM
Many of us have the new PSO-1 4x24 v scope. The scope's elevation turrent and bullet drop chevrons are set up for the 7.62x39 round. I liked the scope and have have one mounted on my .223 VEPR II.
Now, I figure we all know the 7.62x39 drops like a stone at anything past 300 yards, so the drop chevrons can't be right for the zippy .223. Here's a link to a nice diagram of the reticle in question.
http://www.nightvisionweb.com/images/posp_4x24_ret_400_descr.gif
The following link has some nice drop tables for our favorite rounds.
http://www.ada.ru/Guns/ballistic/index.htm
After reviewing the drop tables on the site, here's what I conclude. For a PSO-1 4x24 v with the 7.62x39 rangefinder/reticle mounted on a .223 rifle which has been zeroed in at 100 meters.
2nd chevron (200 meters): The .223 bullet strikes 4 cm high (or 1.6 inches high).
3rd chevron (300 meters): The .223 bullet strikes 16.3 cm (or 6.54 inches) high.
After playing around with some ballistics software, I have come up with some chevron dead-on range estimates for the .223 round in which I am fairly confident. Again, the scope in question is the PSO-1 4x24 v with 400 meter reticle/rangefinder calibrated for 7.62x39, but mounted on a .223 rifle.
Using the software I plotted a bullet path for a 55 gr .223 bullet. I then traced the curve out past 200 meters until the bullet had dropped the additional 1.6 inches. Rounding a bit, I get 220 meters. That is, on a .223 rifle - with the scope zeroed at 100 meters, the second chevron should be pretty close to dead-on at 220 meters.
Following the same approach, I followed the curve on past 300 meters until the bullet had dropped the additional 6.52 inches. I rounded to 335 meters.
In summary: (with both rifles zeroed in at 100 meters)
7.62x39: 1st chevron 100 m, 2nd chevron 200 m, 3rd chevron 300 m
.223 Rem: 1st chevron 100m, 2nd chevron 220 m, 3rd chevron 335 m
Somebody with some really good ballistic software, please plot the two rounds out and let us know for sure.
Now, I figure we all know the 7.62x39 drops like a stone at anything past 300 yards, so the drop chevrons can't be right for the zippy .223. Here's a link to a nice diagram of the reticle in question.
http://www.nightvisionweb.com/images/posp_4x24_ret_400_descr.gif
The following link has some nice drop tables for our favorite rounds.
http://www.ada.ru/Guns/ballistic/index.htm
After reviewing the drop tables on the site, here's what I conclude. For a PSO-1 4x24 v with the 7.62x39 rangefinder/reticle mounted on a .223 rifle which has been zeroed in at 100 meters.
2nd chevron (200 meters): The .223 bullet strikes 4 cm high (or 1.6 inches high).
3rd chevron (300 meters): The .223 bullet strikes 16.3 cm (or 6.54 inches) high.
After playing around with some ballistics software, I have come up with some chevron dead-on range estimates for the .223 round in which I am fairly confident. Again, the scope in question is the PSO-1 4x24 v with 400 meter reticle/rangefinder calibrated for 7.62x39, but mounted on a .223 rifle.
Using the software I plotted a bullet path for a 55 gr .223 bullet. I then traced the curve out past 200 meters until the bullet had dropped the additional 1.6 inches. Rounding a bit, I get 220 meters. That is, on a .223 rifle - with the scope zeroed at 100 meters, the second chevron should be pretty close to dead-on at 220 meters.
Following the same approach, I followed the curve on past 300 meters until the bullet had dropped the additional 6.52 inches. I rounded to 335 meters.
In summary: (with both rifles zeroed in at 100 meters)
7.62x39: 1st chevron 100 m, 2nd chevron 200 m, 3rd chevron 300 m
.223 Rem: 1st chevron 100m, 2nd chevron 220 m, 3rd chevron 335 m
Somebody with some really good ballistic software, please plot the two rounds out and let us know for sure.