Range Report Long- vs short-action

[Smithcollector]

Looking at the reloading manuals and comparing 30-06 to 308, or 280 to 7mm-08, the short-action cases are clearly more efficient, getting equal or more velocity from less powder. It seems like it's a free lunch to switch to the short-action version if there's one available. So what's the tradeoff - what does one give up by using the short-action version ie a 308 over a 30-06?

 

[MontanaMarine]

Re: Long- vs short-action

If you load the longer cases to their potential, they are good for about 200 fps gain over their short action counterparts.

 

[desertrat1979]

Re: Long- vs short-action

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: MontanaMarine</div><div class="ubbcode-body">If you load the longer cases to their potential, they are good for about 200 fps gain over their short action counterparts.</div></div>

ditto, you have more room to go if you want more speed. Sure you can reach the same velocitioes with a .308 as you do in an 06, but you will prolly be looking at some pressure signs when you get there. Also, with other calibers you mentioned you are comparing apples to oranges. Many of the .260, 6.5, 7mm and such are generally flatter shooters off the bat. Some can go the distance but most peter out past a specific range and lose stability/energy
For example the .208 AMAX, .308 can send em to a little over 1k at its best before it becomes unstable, barrel velocity 2400 to 2650 fps. 30-06 gets you to 1k and can go another 2-300 yds with around 2600-2800 fps. 300WM will net you 2800-3000+ fps and get you to 1200-1400 yds.

Not saying these are absolute numbers, but the general consensus of info I have seen puts these numbers in the laws of averages. Other factors, shooter, rifle, ammo, conditions all play a role as well.

Some prefer the short action for rigidity as well.

 

[GCMxVeGeTa]

Re: Long- vs short-action

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: MontanaMarine</div><div class="ubbcode-body">If you load the longer cases to their potential, they are good for about 200 fps gain over their short action counterparts.</div></div>

What about an AI short case? Difference in FPS on average?

 

[bohem]

Re: Long- vs short-action

AI cases gain more as the bore size decreases.

A 22-250 AI will gain more than a 300 Savage AI (300 Savage is the parent case to the 22-250) because there's more room that is taken by shoulder taper as opposed to bullet with the smaller case.

I have a 24" barreled 30-06 AI with a 24" barrel that runs about 25 fps than my 26" barreled 30-06 with the same bullet/powder. It picks up 1.4gr of water capacity in the fired cases.

Considering that you usually gain 25-50 fps per inch of barrel in that barrel length region, you're looking at a 75-100fps gain for the AI version in this case.

EDIT: Also, my dad has a 308 that's built with identical parts to my 30-06, the only difference is the case. My 30-06 gets easy (no overpressure signs) 2925 fps with 178 Amax and my dad's rifle is struggling to reach 2650 without stretching primer pockets. 275 fps muzzle velocity translates to the difference of a 223 vs. a 22-250. Many reloading manuals have extremely conservative 30-06 data because of the number of old rifles chambered in it that can't take modern loads. The garand is a very good example of that.