I got out the Chrony on Sunday and set out to check a bunch of loads in my Model 8 in 30 rem. I learned that what the fps are in one rifle is not necessarily the same as another. I have a handloads that I used 35.5 grains of 748 with a 150 grain Speer Hot Core round nose that registered 2215fps in my 81, but a five shot average in the 8 was 2352 fps. Only a 17.5 fps standard deviation on a five shot string and accurate. But I think I need to back off the throttle a grain or two, after all, my model 8 is 104 years old!
I also check some 1960's vintage Remington factory ammo with the 170 gr bullet and they ran a five shot average of 1959 fps. I think that load was rated at 2000 fps, so 50 years later, I'd say the ammo held up fine. Std. Dev. was only 34.
And finally I checked the velocity of the last 5 rounds of a 1950's box of Remington 160 grain full metal jacket ammo. Time must be catching up with the ammo, five shot average was 2199 fps, but had a 330 fps spread with a 144 fps std dev. One round clocked 2336 fps! Quite a warm load.
Questions or comments welcome.
Mike
Chronographing the Model 8
Re: Chronographing the Model 8
Nothing unusual about varying chronograph results. My brother has a Marlin 1894 41 Magnum identical to mine-about 50 numbers later by serial number. His chrongraphs 50 fps faster than mine with factory loads from the same box and the same difference with my identical handloads. At one time I had two SKS-45's and one was consistantly 40-50 fps faster.