Reply With QuoteWith Lapua brass your probably a little warm. With tight headspace and a short throat, I ran at 41-42 gr. IMR 4064 with 178 amax reaching 2800 fps. Using a 26" Shilen Select Match barrel.With Lapua brass.
I have used the Pressure Trace on just one cartridge and rifle so far -- the 6.5 Grendel in a TC Encore.
The first thing I discovered is that the lug under the chamber significantly reduces the strain seen even at the top of the chamber where my gage is located.
I therefore tested close to ten loads from two different powder manufacturers to calibrate. Now when the system says "50 ksi" I know that it means my load has a good chance of being within about 5% of that pressure when tested in the powder manufacturers' pressure breeches.
It dies NOT mean that actual pressure is 50ksi, only that the number has a good chance of being consistent with published data.
BOTTOM LINE: When possible, test against known loads before assessing your own loads. If you have a wildcat, try at least to pressure test with known loads in the parent case.
With Lapua brass your probably a little warm. With tight headspace and a short throat, I ran at 41-42 gr. IMR 4064 with 178 amax reaching 2800 fps. Using a 26" Shilen Select Match barrel.With Lapua brass.
I have run 44gr imr 4064 with a 175 SMK but it was in Winchester brass,, good load.
Yes, that gets cautioned against by the folks at RSI, you have to know exactly what the dimensions of the barrel outter diameter are. A lug will mess with that pretty good.Originally Posted by JASmith
We have used Ruger's or Savages without a nut on short action cartridges. You can also jump to the SAAMI website and they list all the various mfgrs part numbers for reference ammo. So you can call whichever you prefer and order tested reference ammo if you wish for a good calibration.
In the mid 1970s Paul Harvey on his radio program said "Research scientists have discovered that Orange Juice causes cancer in gay rats"
Are you saying these rats may have ingested fluoride or do you and Dakker live in Colorado and are on a John Denver rock mountain high.
In the mid 1970s Paul Harvey on his radio program said "Research scientists have discovered that Orange Juice causes cancer in gay rats"
Are you saying these rats may have ingested fluoride or do you and Dakker live in Colorado and both of you are on a John Denver rocky mountain high.
i think i will stick with sticky bolt lift and condition of the brass to tell me where my max is. It has worked for me for over 40 years. of course i am not one of those shooters seeking max velocity.
I am not one of those people who believe everything some computer spits out.
Just depends on what you want to call "max", and what you are after.
Assuming there is no soft brass, or other issues in the burning curve; my work with the 308 *TENDS* to show stiff bolt lift when you are above 70,000 PSI.
I also don't run full pressure on most things anymore. I'm more of a light and tight(groups) shooter. Keeps components lasting a loooooong time.
Still running some brass with heastamps from the 60's!
I went down the rabbit hole of trying to see how much speed I could get out of my various rifles/calibers. Didn't break anything but I did learn that when I stuck to working UP my loads from a modest start I usually found a load that was super accurate and had more than enough speed to get it to the target at any distance I was interested in. Any more powder, speed, pressure, was overkill and also a pain in the butt when it came to hot weather.
I figure that if I need to reach out farther I'll just get a rifle chambered with a cartridge designed to shoot that far.
Can have some challenging fun with slower moving stuff sometimes. Couple years back MZ5 came up and we did some shooting to a mile. My 308 was changing those barrel lids at something silly like 850fps.
Makes reading wind a real trick!
Best answer right there. Reason why I sold my 6.5 CM and picked up a 338LM.
Somewhere between the starting load and the maximum will show the best accuracy, I usually end up with a load that is about 2 grains off max, very safe, very accurate.
Last hunting season I tagged a nice buck and a huge black bear with my 308, both were taken with 165 grain bullets, one shot each.
The 308 doesn't have to be loaded to dangerous levels to be very effective and accurate.
When I get the urge to reach out there , I shoot 300 mag or borrow a buddy's 338 Lapua.
The 308 is not one of the above, when used as designed it will fill the freezer and still have enough in the tank to hit gongs at respectable distances.
Somewhere between the starting load and the maximum will show the best accuracy, I usually end up with a load that is about 2 grains off max,
Years ago one of the techs at Sierra suggested that if you start 2 grains below maximum with their bullet data more often than not you will end up with a very accurate load and I have found that to be true more often than not.
I have found that two grains below max works well for me, I do have some loads that are book max and find no difference in hunting situations.
i am saying that trying to make a 308 into a 300 mag isn't possible.
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