High BC .257 bullets?

skip AI · #8 10-14-2006, 11:02 PM

Brian, thanks for the link. Lol it sure gets windy when it wants to!

What do you reccomend for my intended purpose?

cheers

Ernie · #9 10-15-2006, 03:15 AM

Kirby what twist rates would the 142 & or 156 require say out of a 18" Specialty Handgun in say a 25 WSM?

skip AI · #10 10-15-2006, 04:27 AM

I've been playing with the ballistics software and have found that if I can get the Berger VLD 115gn going 3400fps, it would half the drift of the Nosler BT 85gn at 3600fps that I am currently using.

Do you think I could achieve such velocity?

cheers

brianwinzor · #11 10-15-2006, 05:42 AM

Skip AI, Yes! You could get 3,400 fps with the 115 Berger VLD in your 25/06AI, extraction would be stiff, and the cases would almost certainly last just the 1 shot, maybe 2 if the primer doesn't fall out when seating.

My 20 years experience with the 25/06AI, has taught me that if I run the 100 grain bullets in the 3,600 - 3,650 fps range, or the 115/120 grain bullets in the 3,300 - 3,400 fps range, then case life deteriorates fast and 3 - 4 shots is about the norm. I have learnt that if I restrict the velocity to about 3,550 fps with the 100 grain bullet and 3,250 - 3,275 fps with the 115 grain bullet then I can expect at least 7 reloads from my cases. Currently have got over 500 shots from 60 cases, with only about 2 failures. Hope the above helps. Brian.

skip AI · #12 10-15-2006, 06:15 AM

Brian, are you saying that running them at 3400fps would not be within safe working pressure, which could lead to something going wrong?
What powders have you found to work best with the 115gn mark? I prefer ADI powder myself.
Just out of interest what have you been using your 06 for? target shooting?

cheers

remingtonman_25_06 · #13 10-15-2006, 11:18 AM

3400fps sounds a bit high, but maybe. The bigger bullets as someone already stated have the benefit of a lot less wind drift at longer ranges. They also hit harder and have more retained velocity.

brianwinzor · #14 10-15-2006, 12:09 PM

Skip AI, Yes! I am definitely saying that 3,400 fps is way too hot for the 115 grain bullet in a 24 inch barrel, and at least 100 fps over what is normally a safe maximum. 3,400 fps may be just achievable in a 30 inch barrel.

I found that with the Nosler 115BT, 63.0 grains of H1000 gave consistent sub 0.5 moa accuracy, velocities in the 3,240 - 3,275 range (depending on temp), and life was sweet.

However, I ran out of my supply of H1000, and even though ADI AR2217 is supposed to be the same powder, I paid the price for not working up again, as it took just 1 shot, 3,482 fps, and a blown primer with 63.0 grains of AR2217 to quickly discover that there is significant lot to lot variation. Now 60.0 grains became the maximum, but velocity is down and accuracy isn't the same.

I then switched to using 62.0/Reloader 25 as on first test it gave 3,292 fps at maximum pressure. However, I have now abandoned that powder with this bullet weight, as since the original test it is all over the place, as velocities are varying by as much as 100 - 150 fps depending on temperature.

Since then I have mainly been using Richard Graves Wildcat 125 grain ULD's. However, if I did for some reason return to using the Nosler 115BT, I would try some AR2225 (HRetumbo) next as I think there is a reasonable chance of
cramming enough in (about 64.0 grains) to produce enough pressure and velocity.

I have done a lot testing with my custom 25/06AI (SakoL61R, Shilen 24 in barrel, Fajen Laminated stock) to see what the case is capable of, but have been using it on medium game here in Oz. If you are interested I could email you a file with the data I have collated on bullets from 100 - 156 grains. Regards, Brian.