I know how to read pressure gents. Never had a sticky extraction. Primers still had rounded edges. No ejector marks of any kind. No expansion near the web of the case. I found that TAC is only 20-40 FPS faster in my longer barreled 308s.
Velocity checked on Labradar and MagnetoSpeed. As a responsible sportsman and shooter I would not have posted a load that was marginal on pressure. I shoot some like that but would never post them for the world to see.
My copy was a little older, but the new load book from Ramshot sure isn't in the 75K MPSI range if he adds 0.3 grains to the Sierra load.
I know you were an officer, so I suppose I'll have to dumb it down for you. 46 grains is significantly different than the 57 to 61 in your post (that's more powder than a 30-06 will use with TAC and 155s). 2925 fps in an 18.5" barrel is more than Ramshot is achieving with their 24" barrel. A barrel 5.5" shorter than the test barrel is going to be slower, not faster. So, since velocity equals pressure, the 18.5" 2925 fps load in question is either a: significantly over pressure in order to achieve such high velocity, or b: the poster's chronograph is off.
The Barnes Data is what I used since the 155 Scenar is longer than the typical 155 grain bullet from any other maker because the entire nose is hollow almost to the ogive...maybe a little past. Maximum was 48.2 grains of powder to yield 2980ish FPS. Try it and see. In contrast a 46.2 grains of Varget with all the same components yields 2775 from the rifle above. 2812 from a 20 inch. And 2889 from a 22 inch. Some powders peak faster than others.
My copy was a little older, but the new load book from Ramshot sure isn't in the 75K MPSI range if he adds 0.3 grains to the Sierra load.
I know you were an officer, so I suppose I'll have to dumb it down for you. 46 grains is significantly different than the 57 to 61 in your post (that's more powder than a 30-06 will use with TAC and 155s). 2925 fps in an 18.5" barrel is more than Ramshot is achieving with their 24" barrel. A barrel 5.5" shorter than the test barrel is going to be slower, not faster. So, since velocity equals pressure, the 18.5" 2925 fps load in question is either a: significantly over pressure in order to achieve such high velocity, or b: the poster's chronograph is off.
The Barnes Data is what I used since the 155 Scenar is longer than the typical 155 grain bullet from any other maker because the entire nose is hollow almost to the ogive...maybe a little past. Maximum was 48.2 grains of powder to yield 2980ish FPS. Try it and see. In contrast a 46.2 grains of Varget with all the same components yields 2775 from the rifle above. 2812 from a 20 inch. And 2889 from a 22 inch. Some powders peak faster than others.
The online Barnes data showing 48.2 grains as max is with 150s. Their 155 Match Burner data tops out at 46.6 grains, for 2904 fps.....in a 24" barrel.
155 Matchburner is 1.256 in. long 155 Scenar is 1.290 in. long 150 Barnes TSX is 1.301 in. long
Might be an oversimplification, but it feels safer going with the longer bullet data and stop if I saw pressure or since this is a hunting gun, show any signs of flash. I actually went up to 47.5 and besides having a wide plateau in speed the SD and ES and group sizes were larger.
I have never tried to work up a fast 308 load. I work for accuracy and what ever speed the bullet goes ,it goes. I chronograph only after I get satisfactory accuracy. I like to have all my 150 grain bullets in the 2675 to 2750 range, and near the same for 165s. I like to see 180 go 2475 to 2550 from my 308s
If that for some reason seems as it it's not powerful enough I take out a more powerful rifle.
I I have 270s the shoot 150s at the top end of 2900 and one that touches 3000. I have a few 30-06 that can drive the same bullets as my 308s a bit faster with very good accuracy. (as if that mattered)
If even more is wanted I have a 358 Winchester, two 9.3X57s, a 9.3X74R a 9.3X62 and a 375H&H and a 404 Jeffery.
So I see no reason to hotrod any gun just to hot rod it.
If it shoots well with a hot safe load, that's great. My 25-06 and two of my 270s do just that,. But I shoot what seems to do well for accuracy with good game bullets' that don't break up badly on impact. I don't care about speed for speed's sake.
My 6.5, both of my 308s, one of my 30-06s and my 8X57 all shoot best with moderate loads and they kill things just fine. I have been doing it for a LOT of years and have learned that chancing more velocity just to make a bullet go faster is mostly a waist of time in the real world for hunting.
I’ve had good results, accuracy and on-game performance, running .308s a couple of grains off the top, pretty much like a .300 Savage, but my shots are close. With a new one on the way, I invested in some 130gr TTSXs just to see if they're all they’re cracked up to be. 3100 is supposed to be doable with those; even 3200. We shall see.
I use 46 of TAC over 150 NBT all the time. I think it's fairly common max load for TAC and 150s. I get 2850 fps from 20" barrel.
And easily Submoa most times you pull the trigger. Has that been your experience?
Yes. I used that combo for a few years on whitetail, hog, javelina and mule deer. Nothing took a step and it always exited even through both shoulders of an old mule deer.
I’ve had good results, accuracy and on-game performance, running .308s a couple of grains off the top, pretty much like a .300 Savage, but my shots are close. With a new one on the way, I invested in some 130gr TTSXs just to see if they're all they’re cracked up to be. 3100 is supposed to be doable with those; even 3200. We shall see.
Pappy348, you can do it with TAC.....those 130's are the ticket in a 308, can be pushed to 270 speed.