You know I was looking thru my old copies of Handloader. I came across the No. 174 April 1995 edition. It has some 7mmSTW loads wrote by Layne Simpson. Wow, there was some speeders in there. Let me point out a few.
140gr Sierra SBT, H4831, 78gr-81gr, 3348-3417fps (decently reasonable)
140gr Nosler BT, RL22, 78-80gr, 3404-3463fps (about right with current data)
140gr Nosler BT, H1000, 86-88gr, 3373-3516fps (getting hot in here)
140gr Nosler Partition, 7828, 80-83gr, 3407-3498fps (even hotter)
160gr Speer GS, RL22, 76-77gr, 3165-3219fps
160gr Speer GS, H1000, 80-85gr, 3149-3319fps (smokin)
160gr Partition, H5010, 87-90gr, 3182-3311fps, (wow)
A-Square factory loads in 26.5" Custom 700, Schnieder barrel, wow, look at these speeds.
140gr Nosler BT, 3512fps
160gr Partition, 3315fps
160gr Sierra SBT, 3303
I guess if I were "Big Green", or one of the other major firearms/ammunition companies, I would be real conservative on factory ammunition as well. One thing you don't hear much about is the degree to which an individual barrel can take hot loads. Most folks think that, if you have ten Shilen barrels all in the same caliber, and all chambered with the same reamer and screwed on the same action - they would all develop about the same velocity, right? Or at least develop about the same velocity at the same pressure. This is true most of the time, but . . .
Over the years, I have seen some pretty extreme examples of very "fast" or very "slow" barrels. In about 1995, I built a local rancher a 7 STW on a Remington action with a 27" Shilen SS barrel. He called me about a week later and reported getting almost 3500 fps. I said "Wow" - that's pretty fast for a 140 grain bullet. He replied he was using a 160 grain bullet. I immediately went through a series of questions regarding pressure signs, and concluded he must have faulty chronograph. So I loaned him mine. Almost the same velocity. Then we tried some factory Remington 7 STW loads with a 140 grain bullet. They were about 150 fps faster than they were supposed to be. I don't know what is so special about this barrel, but he has turned down $2000 for the rifle.
In about 1998, I put a Shilen 26" barrel on another Remington and chambered it for .300 Weatherby. This gun couldn't make 3,000 fps with any 180 grain bullet without showing pressure signs. The gun shoots pretty good and the barrel seems resonably smooth, but just can't make the speed. And factory ammunition is only going a little over 2900. I have used this reamer on a bunch of other rifles and they were able to reach what we expected in terms of velocity. This guy would probably let this gun go for a twelve pack of Miller light . . .
__________________
A man has got to know his limitations . . . . .
Laynes article was on three different rifles. He got that velocity on all of them. Of course when you are layne, you can do that. One was a TC with a factory barrel. Reason I posted this was this round puzzles me. There are two variations in load data. Hot and cold. No inbetween. I see pressure signs from factory winchester ammo on brass I bought off another guy. And his wasn't producing 3300fps with 160gr bullet. Thats the only reason I posted it. Hey if Layne can do it, I am sure we can.
I want this rifle I have a Sako75 stainless to last a long time. I don't plan on shooting the barrel out of it like I have other guns. At least in the next 20 years. So I have a few mild loads that work in the velocity range I wanted it to work. I have 160gr accubond load with 77gr of H1000 that works well and I get ~3050fps. I figure if I drop it down those extra 3 or 4 grains (compared to layne's and other published loads) with subMOA performance, I should get 1500 shots of real nice hunting accuracy.
That is some pretty sound logic, IMO. I doubt if any game animal is going to know the difference. Sometimes I think folks might be better off if they didn't own chronographs . . . .
__________________
A man has got to know his limitations . . . . .
layne's rifles were all custom barreled jobs, custom barrels run faster than production, this particular caliber seems to run 100-140 fps faster from a custom barrel, I tried the loads with the 140 gr nosler and 88 gr of H-1000 ran 3602 fps out of a 26" lilja barrel, just a lil bit sticky on the bolt lift so I cut it back to 86 gr and still get 3550 fps and about a .4 3 shot group with 16 fps extreme spread. to preserve barrel life try some AA8700, it doesn't burn nearly as hot as most powders and the ball powder is not as abrasive on the throat, just remember it is very dirty unless you load to around 60,000 psi, just the nature of ball powder
RR
I own a .22-284. It is fast (at the expense of barrel life) - might do 4,500 with a light bullet - but 6K just ain't possible. In fact, there is an upper limit of velocity based on the rate of the expanding gas - even the .50 BMG necked down to .17 won't go 6K.
__________________
A man has got to know his limitations . . . . .
own a .22-284. It is fast (at the expense of barrel life) - might do 4,500 with a light bullet - but 6K just ain't possible. In fact, there is an upper limit of velocity based on the rate of the expanding gas - even the .50 BMG necked down to .17 won't go 6K.
Totally agree. I know 5 guys with a 22-284 and noone gets 6K. Even people with a 22-243 middestead don't get near that.
Old 7mmSTW loads
