James goes over barrel length and velocity for hunting long range with a 7 PRC

Very interesting velocity recording, very different from what Hornady advertises for that ammunition out of a 24" barrel, I would be all ears on your opinion on this
This Barrel is measured from chamber where where the case starts to muzzle
My guess is they measured from receiver / shoulder to muzzle and adds almost an inch
Also bore tightness differs.
 
Great information and gathering.

Maybe you can add another lever of data during same test of muzzle blast or decibels.
I had a thread going which petered out but wanted some kind of scientific answer to when short is too short for ears and muzzle jump. (target re-acqusition)

Looking forward to the rest of the series.
I think the .280AI has already proven what your going to see in conclusion.

Thanks again!
 
For the max range numbers are they at going into subsonic velocities for calculations? Just trying to see where you get numbers from. Not sure if you have the range (at your location or near by) to verify velocities per distance of what the computer projects? I know temp and humidity do play a part, but should still be within 100 yards possibly? Don't take any of these questions the wrong way as some might.
 
What I should also ask is are the maximum numbers posted include reliable expansion of the bullet?
Thanks for the reply
All bullets work a little different
This is a general rule that cup and core bullets (lead core copper jackets) will expand at a minimum retained velocities of 1600 fps left on impact on an animal
I base this discussion on experience and testing

Retained velocity also is different at different station pressure or elevations

Rotational rpms left to stabilize the bullet is used to make sure the bullet is stable near transonic, we dont hunt in transonic but it guarantees stabilization at mach 1.4 - hunting distance or velocity. This is why we use a stability factor
1.6 minimum is my guidelines for my students
 
Last edited:

Recent Posts

Top