185 Juggernauht Velocities?

[TrxR]

Does anyone know what their velocity is and the target at a 1000yds with a 185 juggernauht out of a .308? If so what is your starting velocity ? What twist and what length barrel?

I got a new rifle being put a together with a 30" 10.33 twist and am going to be using 185's. The only concern is that we are using Electronic targets and need to be above the speed of sound at the target for it to register.


Thanks

 

[skiutah02]

Even with my "slow" velocity at the muzzle of 2685fps at 60oF and 960 alt they make it to 1000 supersonic no problem. Kriger 28 in, 1:11 twist. Drew

 

[watercam]

Fortunately you need to be supersonic to be stable as well. If you do not know about JMB Ballistics you should. An online ballistics program that is quite good at telling you what you need to know. From my experience I was able to start them at 2660 fps w/ Varget and roughly 2750 or so with H4350 (30-32" barrels). Either one will be supersonic out to a grand (about 1400 fps). They are a lesson in heavy vs. lighter bullets at long range as even though the 155s start around 3000 fps they fall down to about 1300 @ 1000 while the 185s, while starting slower, maintain a higher down range velocity. Good luck with your shoot!

 

[Dos XX]

Go here. Select your bullet. Plug in your environmental info and it will output what you need. The 30" and 32" barrels I have shot that bullet out of have liked it around 2750 fps.


http://www.jbmballistics.com/cgi-bin/jbmtraj_drift-5.1.cgi

 

[Tempest]

Just did a chrono yesterday.

90F, 680ft corrected alt, around 2705 FPS w/ a 29" barrel.

Typically 2670 in cooler weather.

 

[barefooter56]

TrxR,
Go to our website and access the BALLISTIC CALCULATOR under the BALLISTICS tab on our main page. Be sure to enter your ALTITUDE! 1226 fps at at the target is a safe number. A 28-30 inch barrel and a slow burning powder can be your friends in this endeavor. Check out the TWIST RATE CALCULATOR also to get the stability factor information for your barrel twist also. 1.5 and up is good!

 

[savageshooter86]

I'm at 202 ft elevation. 30" barrel pushed them 2755fps at muzzle. At 1000 yards target velocity is 1350. 1:10 twist

 

[TrxR]

Thank everyone. Im at under 500 feet above sea level. It looks like I should be fine with the 10.33 twist.

Thanks