Author Topic: 16.25" Barreled Ballistics (Read 630 times)

Big Blue · « **on:** January 17, 2005, 12:42:37 PM »

What can I use to estimate the ballistics of a 16.25" barrel, when all of the load data for rifle calibers seems to be from 24" barrels? In particular a .308. I'd like to know where my bullet will hit at 250 yards, when the only range I have available is 100 yards. Looking at rifle data, I should set my scope for about 2.5" high at 100 for a maximum point blank range using a 6" diameter kill zone. But what about the 16.25" barrel?
Thanks,
Don

Gregory · « **Reply #1 on:** January 17, 2005, 12:48:42 PM »

Quote from: Big Blue

What can I use to estimate the ballistics of a 16.25" barrel, when all of the load data for rifle calibers seems to be from 24" barrels? In particular a .308. I'd like to know where my bullet will hit at 250 yards, when the only range I have available is 100 yards. Looking at rifle data, I should set my scope for about 2.5" high at 100 for a maximum point blank range using a 6" diameter kill zone. But what about the 16.25" barrel?
Thanks,
Don

What caliber are you shooting? I've owned 16.25" barrels in many calibers and may have chrono data for you. There is a rule of thumb that you lose 100 FPS for every 2" of barrel, if I'm remembering it correctly.

Big Blue · « **Reply #2 on:** January 17, 2005, 12:53:00 PM »

Greg,
That 100 FPS rule would help a lot. I can use some different load calculators to figure that in. I'm using a .308, and 150gr. Barnes X bullets.
Don

Gregory · « **Reply #3 on:** January 17, 2005, 01:06:35 PM »

Big blue

Sorry missed seeing the 308 in your original post. I've had 16.25" Contender barrels so can't help you there.

Here's a table that might be useful:
http://www.remington.com/ammo/ballistics/tableinfo.htm

Big Blue · « **Reply #4 on:** January 17, 2005, 01:18:05 PM »

Greg,
Thanks, that table does help a lot. There is a much lower loss of velocity than I originally thought.
Don

xphunter · « **Reply #5 on:** January 17, 2005, 03:04:02 PM »

About 35-40 fps loss per inch has been closer in my experience. I had also held to the 50 fps rule till my results that much--to my surprise and delight!