Curious..what are the highest chrono'd 308win velocities using a 26-28" barrel?

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sgt.rock

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I have a T/C prohunter 308win with 28" barrel that I have yet to really test drive. I have hundreds of 150/165/180gr bullets. What type of velocities can be gotten with the extra barrel? What is the highest velocity you have personally chrono'd and what bullet/powder/primer got that speed for you?
I am not asking for comments like "why need max speed" and accurate loads are usually less than max loads. This is pure curiosity as I truly wonder how much closer the gap is between 308 and 30-06 with all the newer components we have these days. Can a 308win literally equal the 30-06 with good powders and extra barrel?
 
shouldn't the comparison be limited to "all things equal except for the bbl length"?
because otherwise I can load a "slow 30-06" and a "bit over max 308" to prove it can be done :)
 
I guess I am just curious as to what the safe max speed is nowadays in the .308win using powders etc that werent available yesteryear. Combined with an extra 6-8" of barrel over standard tubes, I just wonder what can be achieved these days.
 
Keep in mind that there is no way to know what YOUR results will be unless you try them in your rifle.
I have seen two identical 30-06 rifle [both 110 Savages] with max safe loads. One produced 2840 with
a 180, the other only got to 2725 before pressure signs showed. These rifles both had 22" tubes. Dave.
 
Eagleye said:
Keep in mind that there is no way to know what YOUR results will be unless you try them in your rifle.
I have seen two identical 30-06 rifle [both 110 Savages] with max safe loads. One produced 2840 with
a 180, the other only got to 2725 before pressure signs showed. These rifles both had 22" tubes. Dave.
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Mainly looking to see what people have achieved with their own guns and what they used to get it. I fully understand fast/slow barrels and different chambers being wild variables in actual speed you get. Just looking for individual anecdotal data from nutters.
 
in the link I have provided, the most fps difference between 22 and 28" in 308 is 128fps
even with a better powder that's not enough to beat the 30-06 extra case capacity
 
sgt.rock said:
I have a T/C prohunter 308win with 28" barrel that I have yet to really test drive. I have hundreds of 150/165/180gr bullets. What type of velocities can be gotten with the extra barrel? What is the highest velocity you have personally chrono'd and what bullet/powder/primer got that speed for you?
I am not asking for comments like "why need max speed" and accurate loads are usually less than max loads. This is pure curiosity as I truly wonder how much closer the gap is between 308 and 30-06 with all the newer components we have these days. Can a 308win literally equal the 30-06 with good powders and extra barrel?
Click to expand...

No. As long as you are being fair and letting the 30-06 benefit from the good powers and extra barrel as well, then 06 will always outperform because it simply has more powder available.

How much longer is your 28" barrel over your last one? IN my experience, you get between 25-50 FPS per inch of barrel. This could be quite a bit less or quite a bit more depending on a bunch of things, but 50 FPS is a decent rough guide. Its also a diminishing return past 26".

I haven't done any 308 win load development. All of my experience with shooting 308 cal bullets at top speeds involved a 2" straight taper barrel @32" long set in a solid 4" universal receiver block with a custom cut 300 RUM chamber. Not even remotely applicable to your situation, but top speed with a 147 gr M80 was just shy of 4300 FPS with H4831 SC and CCI magnum rifle primers. I doubt the barrel would have lasted more than 100 shots at that velocity, IF that. I would be surprised if any 308 win could crack 3k, but then I get surprised all the time.
 
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Don't the Palma guys launch a 155gr around 3000 with a 308? But having to use high end brass with small primer pockets probably means high pressure too.
 
Ganderite said:
My Palma load (32" brl) is about 3050 fps. 47.5 Varget 155gr Berger. I would say a 28" would do around 2950 fps.
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I did a calibrated Quickload estimate for my 22" Savage 30-06 with 155AMAX and 62gr H4350 I should be able to beat that. If only my chrony worked in the rain...
 
legi0n said:
I did a calibrated Quickload estimate for my 22" Savage 30-06 with 155AMAX and 62gr H4350 I should be able to beat that. If only my chrony worked in the rain...
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That is a lot of powder in there. I shoot 150gr sst with h4350 someplace around 59-59.5gr (cant remember exactly) it runs a hair shy of 3000fps.
 
hometownhero said:
That is a lot of powder in there. I shoot 150gr sst with h4350 someplace around 59-59.5gr (cant remember exactly) it runs a hair shy of 3000fps.
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yep, it is, but that's the load both Lee and Hodgdon list as max.
I will work charges up until I either surpass the 308velocity (the purpose of this thread) or the rifle complains.
I usually shoot 180+gr in 30-06 but this time it's for the science :)
Like Eagle Eye said, there are fast barrels and slower ones. The savage I own is pretty fast. The Ruger American, not so much!
 
If we're talking about the 308 and 155 gr bullets, the highest MV at sane pressures will be with a slightly compressed load of Varget. With a 26" barrel I achieve 2900-2950 fps.

Probably the most reliable load for accuracy regardless of rifle. I've never heard of this load not being the most accurate or near most accurate.
 
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