I'm about to start reload for my Rem 700 in 308 and I noticed in the Hornady book that the powder info differs for the 308 and the 308 service rifle. Now is this cause "service rifles", which I assume are gas guns, require different powder loads than a bolt gun? Or is there other reasons?
Hornady load data
- Thread starter frank223
- Start date
Some of the ammo makers think 7.62 NATO isn't the same as .308 Win. As do some of the rifle makers. Before there was an Internet, the two cartridges were the same. Before it was declared evil, I used regular .308 loads in my semi'd Winchester M-14 with no fuss. Hornady et al think in terms of marketing only and don't want to get the people who think the two names are about different cartridges excited.
However, a bolt action can handle far higher pressures than any semi-auto.
However, a bolt action can handle far higher pressures than any semi-auto.
Sun ray"blah blah blah blah. Blaaaaah blah blah."
Big difference between the two comes down to headspace in the fire arm. 7.62 chambers will always be bigger starting some where around 1.634. .308 chambers are 1.630.
Generally mil spec brass is thicker and therefore you should start a grain or two lower when reloading.
I have done my own investigation with NATO surplus and store bought .308. NATO ran right on or slightly above 1.630. The .308 I measured was slight less then 1.630
Big difference between the two comes down to headspace in the fire arm. 7.62 chambers will always be bigger starting some where around 1.634. .308 chambers are 1.630.
Generally mil spec brass is thicker and therefore you should start a grain or two lower when reloading.
I have done my own investigation with NATO surplus and store bought .308. NATO ran right on or slightly above 1.630. The .308 I measured was slight less then 1.630
What I'm asking is why is the load, gr of powder for ###x fps differ for the same case dimensions and the same bullets. For example: 308 win, 165-168 bullets, Varget is 32.6gr to 44gr. 308 win service rifle, 168gr bullets, Varget is 35.5 to 42.7 gr. Both are for 2100-2600 fps. Is the internal dimensions that different that its take different powder loads to create the same fps?
gas systems use pressure to operate, this pressure is stolen from the pressure used to propel the bullet down the barrel, so semi's will always shoot slower with the same load......
Take note on the test firearm if it is listed and barrel length, that is another key factor in real world velocity......
Take note on the test firearm if it is listed and barrel length, that is another key factor in real world velocity......
That's what I was something I was wondering about too. And it does make sense. I'm curious cause I have powder that's listed on the service rifle side but not the 308 win side. I assume that with proper load development and a good chrony, the service rifle loads can be used in a bolt gun?
Yes starting low and working your way up is the way to go.
There are some like myself that will tell you by checking velocity, extraction (sticky bolt lift or pull), flattening of primers, and primer flow will tell you when you are going too far.
There is also the burn rate of the powder to consider. From what I've seen, powder no slower than IMR4320 is recommended for an M-14 (or is that an M-1 Garand???).....
Slower burns powders will still have a higher gas pressure at the gas port, and too high a pressure could damage the op rod. The load may be alright in a bolt gun, but the pressure curve is stretched out too much for a gas gun.
Stan
Slower burns powders will still have a higher gas pressure at the gas port, and too high a pressure could damage the op rod. The load may be alright in a bolt gun, but the pressure curve is stretched out too much for a gas gun.
Stan
yomomma, "blah blah blah blah. Blaaaaah blah blah."
The 308 Winchester and the Nato round is the same cartridge.
Here is a quote from Cartridges of the World, revised 2nd edition, on the 308 Winchester.
It is interesting to note that in the military section of Cartridges of the World, when they come to the Nato round, they simply say to look at the specifications on the 308 Winchester, in the sporting rifles section.
yomomma, "blah blah blah blah. Blaaaaah blah blah."
The 308 Winchester and the Nato round is the same cartridge.
Here is a quote from Cartridges of the World, revised 2nd edition, on the 308 Winchester.
It is interesting to note that in the military section of Cartridges of the World, when they come to the Nato round, they simply say to look at the specifications on the 308 Winchester, in the sporting rifles section.
H4831
yomomma didn't say there was a difference between the .308 and 7.62 NATO cartridge.
yomomma did say the biggest difference between them is military headspace settings, traditionally military chambers are larger in diameter and have longer headspace setting than their civilian counterparts.
yomomma's sarcasm was directed at sunrays stupid comment about using the same load data for gas operated firearms without regard for the burn rate of the powder and port pressure.
I see absolutely nothing wrong with what yomomma said below and agree 100% with his statement, and I do not understand why you posted your comments????????????
Below is from Handloader Magazine
Reloading Semiauto Rifles
By C.E. Harris
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It could very well be this first sentence in his prattle............Sun ray"blah blah blah blah. Blaaaaah blah blah."
Or did you prefer to miss it?
Gentlemen
Moon ray is notories for giving bad advice, my bad, I should learn to put him on my ignore list.
I respect H4831 greatly, but having a M14(just for you Sunday) I have done a lot of reading and there is a difference, ever so slight. For a bolt gun you may never notice. A military semi will let you know, sometimes in unpleasant forms.
So let's not let my momentary laps of reason concerning X-ray ruin this thread.
p.s. kamlooky.........I respect you too
Moon ray is notories for giving bad advice, my bad, I should learn to put him on my ignore list.
I respect H4831 greatly, but having a M14(just for you Sunday) I have done a lot of reading and there is a difference, ever so slight. For a bolt gun you may never notice. A military semi will let you know, sometimes in unpleasant forms.
So let's not let my momentary laps of reason concerning X-ray ruin this thread.
p.s. kamlooky.........I respect you too
It could very well be this first sentence in his prattle............Sun ray"blah blah blah blah. Blaaaaah blah blah."
Or did you prefer to miss it?
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Thanks a lot, yomomma, for your comments.
I don't like to get involved in such subjects, but since we are in it, I looked up the official SAAMI specifications for the 308 Winchester.
The figures look to me to be identical with the figures given in this thread for the Nato round.
Here are the SAAMI specs for the 308.
http://saami.org/PubResources/CC_Drawings/Rifle/308 Winchester.pdf
Bruce
I don't like to get involved in such subjects, but since we are in it, I looked up the official SAAMI specifications for the 308 Winchester.
The figures look to me to be identical with the figures given in this thread for the Nato round.
Here are the SAAMI specs for the 308.
http://saami.org/PubResources/CC_Drawings/Rifle/308 Winchester.pdf
Bruce
