30 May 2009, 07:43
model7LSS.257 Roberts vs. .257 AI
My uncle is thinking about going with the Ackley improved in a custom he is getting done. I know the obvious gains in velocity, but is there any quirks or other drawbacks other than having to reload?
30 May 2009, 07:56
rolltopquote:
I know the obvious gains in velocity,
Please explain what this gain is.
30 May 2009, 08:29
ramrod340quote:
I know the obvious gains in velocity
You really need to take the 257AI gains with a grain of salt. Many are comparing a HOT AI load at or near the limit of brass and rifle to factory 257R data loaded to 54000psi. At equal pressure a gain of 1% velocity for 4% capacity is a decent rule of thumb.
.257 brass is had to find compare to .25/06 brass.
The 25/06 costs less and works fine.
30 May 2009, 09:45
Chop901I used to have a .257 AI. For me, the extra step of making the blown-out case was more aggravation than it was worth.
30 May 2009, 16:51
jeffeossotougher to feed
AT THE SAME PRESSURE
you only gain 50-75 fps
either load a normal to +p, which winchester sells brass for, and several books have modern loads for
or make it a 25-06 ..
or 257 weatherby
if you are only looking for max velocities
or load 115 gr nosler parts. at 2800 and kill any deer, at any reasonable distance, that he can hit them.
30 May 2009, 19:39
N. GarrettWith AI loads you don't have to trim brass very often (sometimes not at all).
You can still use factory loads.
The improved case allows you to operate more safely at the upper limits of design due to reduced bolt thrust and the "cling" of the brass to the chamber at peak pressure.
I like the design, and find it useful for certain shooting and hunting applications.
Garrett
30 May 2009, 22:16
rolltopquote:
Originally posted by rolltop:
quote:
I know the obvious gains in velocity,
Please explain what this gain is.
He must have all the answers. There is no reply.