Slowest STW known to man
#22
Join Date: Jan 2006
Location: Colorado
Posts: 113
RE: Slowest STW known to man
I use one quite often and usually set it up 10-12 feet away. I don't even know it is there now.
This is from their manual:
4. To safeguard the instrument (and to obtain the best results), the projectile must pass between 6 and 4 inches (15 and 10 cm) directly OVER the Twin Lenses in the black plastic boxes at the front and back of the chronograph. These are the chronograph’s "eyes". Attaching pieces of dark-coloured tape on the guide rods (wire rods) at these heights, will help you to accurately aim your shots.
5. The Shooting Area. Every Shooting Chrony and Master Chrony comes equipped with an adjustable-size, triangular shooting area (actually an upside down trapezium) from 8"X8" to 14.5"X14.5" (Fig. 2). All Chronys come equipped with four 9.25" wire rods as well as four 6.5" wire rods with brass connectors attached. The 9.25" wire rods are to be inserted at an angle into the outer holes visible on the black plastic boxes of the unit. On bright, sunny (blue sky) days, install the white plastic diffusers on top of the wire rods (to simulate clouds). The photo-sensors are pointed at the diffusers, which create a white background (clouds or diffusers). On cloudy days, use wire rods for alignment, but without the diffusers.
6. Chronographs should be at least 10 feet (3 m) from the muzzle of a high-powered rifle, but can be closer to guns with a lesser blast. Five feet (1.5 m) is about right for .22 rimfire firearms. Shotguns should be fired at 5 feet because of the spreading pattern of the shot and errant wads. Arrows must be clear of the bowstring before passing over the first "eye".
Hope this helps
This is from their manual:
4. To safeguard the instrument (and to obtain the best results), the projectile must pass between 6 and 4 inches (15 and 10 cm) directly OVER the Twin Lenses in the black plastic boxes at the front and back of the chronograph. These are the chronograph’s "eyes". Attaching pieces of dark-coloured tape on the guide rods (wire rods) at these heights, will help you to accurately aim your shots.
5. The Shooting Area. Every Shooting Chrony and Master Chrony comes equipped with an adjustable-size, triangular shooting area (actually an upside down trapezium) from 8"X8" to 14.5"X14.5" (Fig. 2). All Chronys come equipped with four 9.25" wire rods as well as four 6.5" wire rods with brass connectors attached. The 9.25" wire rods are to be inserted at an angle into the outer holes visible on the black plastic boxes of the unit. On bright, sunny (blue sky) days, install the white plastic diffusers on top of the wire rods (to simulate clouds). The photo-sensors are pointed at the diffusers, which create a white background (clouds or diffusers). On cloudy days, use wire rods for alignment, but without the diffusers.
6. Chronographs should be at least 10 feet (3 m) from the muzzle of a high-powered rifle, but can be closer to guns with a lesser blast. Five feet (1.5 m) is about right for .22 rimfire firearms. Shotguns should be fired at 5 feet because of the spreading pattern of the shot and errant wads. Arrows must be clear of the bowstring before passing over the first "eye".
Hope this helps
#23
Join Date: Jan 2005
Location:
Posts: 505
RE: Slowest STW known to man
I had the same problem with mine. You need to carefully bump up the powder on the STW. The maufactures are waaaaaay too conservative. I own a Sako 75 and was getting anemic velocities with mine. A fellow on another forum had the same problem until he bumped it up a full grain and 1/2.......then 3300+ was achieved instantly. I did the same with mine, and there are no pressure signs at all....none nada. I had to quit before deer season, however, when the weather gets better, I'll be doing some futher testing.....the bottom line is this.....7mm STW published loads are so conservative it isn't even funny.....it's pathetic! I have narrowed my powders to RL22 and IMR 4831.....this story is far from over. The factory Federal premium 150 grainers chronied at 3280 in my sako......wonder what they are using? Not Hodgdon data that's for sure!!! PM me for other findings. Regards, Rick.
#25
Guest
Posts: n/a
RE: Slowest STW known to man
ORIGINAL: jeepkid
Big Country- I got it out of the Nosler book. It's H870, 79.5 grains, at 3112 fps. Little slower then I remembered, but still pretty quick for a rem mag.
Big Country- I got it out of the Nosler book. It's H870, 79.5 grains, at 3112 fps. Little slower then I remembered, but still pretty quick for a rem mag.
#26
Fork Horn
Join Date: Dec 2004
Location:
Posts: 202
RE: Slowest STW known to man
You Need to go Over to Longrangehunting .com and ask Kirby Allen or Fifty Driver he has built a Ton of STW's .
Sounds like the wrong bullet for the Twist of the Barrel. He specializes in that kind of Calibers , He makes a smoking 257 STW at 3900 fps.
Sounds like the wrong bullet for the Twist of the Barrel. He specializes in that kind of Calibers , He makes a smoking 257 STW at 3900 fps.
#27
Guest
Posts: n/a
RE: Slowest STW known to man
ORIGINAL: blaserman
You Need to go Over to Longrangehunting .com and ask Kirby Allen or Fifty Driver he has built a Ton of STW's .
Sounds like the wrong bullet for the Twist of the Barrel. He specializes in that kind of Calibers , He makes a smoking 257 STW at 3900 fps.
You Need to go Over to Longrangehunting .com and ask Kirby Allen or Fifty Driver he has built a Ton of STW's .
Sounds like the wrong bullet for the Twist of the Barrel. He specializes in that kind of Calibers , He makes a smoking 257 STW at 3900 fps.
#28
Guest
Posts: n/a
RE: Slowest STW known to man
ORIGINAL: Ridge Runner
Big,
you at book max big or did you work up a max load for your rifle? sounds like your chamber is oversized causing pressures to run lower, I loaded for a guys 7 RM once like that, was shooting 280 rem velocities so I kept going up while watching for pressure signs, finaly got it where it was sposed to be.
RR
Big,
you at book max big or did you work up a max load for your rifle? sounds like your chamber is oversized causing pressures to run lower, I loaded for a guys 7 RM once like that, was shooting 280 rem velocities so I kept going up while watching for pressure signs, finaly got it where it was sposed to be.
RR
So tonight I loaded up several different combos to try. One was with RL25 78gr to 80gr, and another was H1000 78gr to 80gr. I was getting 3050fps with 78gr of H1000 last year and got average 1MOA accuracy but didn't go past 78gr. Well see how accuracy goes with 80gr.
#29
Guest
Posts: n/a
RE: Slowest STW known to man
ORIGINAL: Ridge Runner
ok big, keep us posted, when I first started loading for my STW in 96, I wasn't getting the velocity I thought I should, kept getting flattened primers, finally out of frustration I called sierra, talked to a tech, he got me straightened out and I'm well satisfied with my STW.
My loads are rem. case/140 gr nosler bt/fed. 215/86 gr. H1000/3550 fps
/160 gr nosler accubns/fed 215/94 gr. wc872/3430 fps
THESE ARE MAX IN MY RIFLE CUT THEM 10%, AND WORK UP!!!!
RR
ok big, keep us posted, when I first started loading for my STW in 96, I wasn't getting the velocity I thought I should, kept getting flattened primers, finally out of frustration I called sierra, talked to a tech, he got me straightened out and I'm well satisfied with my STW.
My loads are rem. case/140 gr nosler bt/fed. 215/86 gr. H1000/3550 fps
/160 gr nosler accubns/fed 215/94 gr. wc872/3430 fps
THESE ARE MAX IN MY RIFLE CUT THEM 10%, AND WORK UP!!!!
RR