7mm-08 muzzle velocities

I really don't think those velocity numbers are real. I'd plug the numbers into a ballistic calculator and shoot it at distance. If the actual drops are what the table tells you for the velocity the chrono is telling than I'm wrong, but 5R won't turn a 7mm-08 into a .280...
 
Well at this point the only thing that could be off is the chronograph , I will still use that load due to it's accuracy, I loaded more and took great care ensuring everything is what it is supposed to be. It's no problem getting 2700 ft with a 150 grain out of that caliber. I'm just curious as to as many changing variables as I had, it is amazing that this all can happen. I have some factory Hornady light mag ammunition that is rated for 3000 ft/sec, and some of my previous hand loads that did 2870 with the old barrel. I will test these and see what the increases are again. I did obtain 3030 ft/sec with my old hand loads in my new barrel. So i do know that there IS an increase of 160 ft sec. at the very least with those loads. I'll set the chrono at 100, 200 and my zero of 250 and see what i get. But with as many things that did change I can see these numbers being possible.

Hopefully i don't shoot the chronograph!!
 
there is an easier way, and it does not risk your chronograph, but if you are confident that the the velocity is accurate, then you won't be worried about a low shot centerpuching the chrono...
 
Ok folks here is what I did.

I went out with my 7WSM and my newly barreled 7mm-08
I checked 5 different loads on the chronograph to see what was happening.I measured and set up my muzzle to chrono at exactly 15ft to the front sensor.

Here are the results.

7WSM Winchester Ballistic Silver Tip 140gr.
my average speed-3124 ft/sec published speed-3225 ft/sec

7WSM Federal Power Shock 150gr
my average speed-2982 ft/sec published speed 3100 ft/sec

7mm-08 Hornady LT MAG 139gr
my average speed-3025 ft/sec published speed 3100 ft/sec

7mm-08 Previous handloads for my factory barrel
my average speed-3005 ft/sec previous tested in new barrel-3030 ft/sec

7mm-08 NEW LOAD 150gr Swift Scirocco
my average speed-2729 ft sec previous tested at 2780 ft/sec.

So, to all that think something is wrong, I can't see it. I cannot do anything more short of doing a full ballistics test at long and specific distances to see what bullet drop is measured at.

I believe these speeds to be accurate within the limits of the chronograph and environmental changes. This load as previously stated shot a 5 shot group of .488" and that was using my coveralls and rubber mats for rests.
I am confident that i can use this on all game aside from large man eating salmon breath bears. which I do not have to worry about in Saskatchewan!! :)


Any questions about my load or setup feel free to contact me.
Anyways Thanks for the guidance I received here. it did ease my mind.
 
Looking at the figures in your last post,it appears that there is nothing wrong with your chronograph,and that your velocities are real.For those that still refuse to believe your numbers,I suggest that they spend some more time reloading for different rifles,so that they learn for themselves that reloading is not as predictable as they think that it is.
 
a smooth barrel and a tight chamber can certainly bump up the velocity...
I know of a 24-1/4" Gaillard barrel in 7mm Rem Mag that has pegged the chrony at 3414 with a 140 and almost 3200 with a 160.....some barrels are faster than others but a good smooth custom barrel is almost always on the fast side. I had a 23" PacNor in 22-250 that pushed a 50 to 3900

I have a 26" 7mm08 here but haven't had time to shoot it yet...hoping it's as fast as yours...
 
It is a very versatile little cartridge , I don't doubt you see velocities of other factory match ammunition, or even a bit higher. I do know that my factory barrel liked bullets moving almost 2900 ft/sec. On some of my test loads(new barrel)a had 150 grain bullets going 2855 ft/sec, with a 5 shot group of 1.3" and .859" with the flyer removed from that, and no pressure signs.and still 3 grains below max load. A guy could work that one too.
 
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