Estimating muzzle velocity for dope chart

[pattimusprime22]

I have a Browning X-bolt hells canyon speed in 6.5 creedmoor and will be taking it out to CO for my first pronghorn hunt. I'm fairly new to long range shooting and no ranges near me in California allow shooting beyond 100yds, so I haven't been able to validate my rifle's dope with Barnes Vor-TX 120gr TTSX BT by shooting at range. Without a chrono is there any good way of estimating muzzle velocity for my 22" barrel? The Barnes box advertises 2910FPS, but I'm assuming that's out of a longer barrel.

I was able to take an axis deer out in Lanai, HI but as that was only a 225 yard shot, I just held a smidge high (with a 100yd zero). Seeing as the pronghorn hunt may be stretching it out a bit further than 200 yards I'd like to have some good estimate for muzzle velocity to plug into the Strelok app to develop a dope chart. This doesn't need to be perfect, just need to be minute of deer (or antelope) out to say 300-350.

Any help is appreciated!

 

[davsco]

hang out at your range this weekend and surely someone will have a chrono you can use. i think rule of thumb is 25-50fps per inch and yeah they prob use 24" though perhaps 26" to make their numbers look better.

 

[mt100gr.]

In my opinion you're walking a dangerous line using an estimate to build a dope chart and in turn hope that minute of critter is good enough.

I would say your effective range for your coming hunt is out to 225ish yards since that's the furthest you have validated. Good luck.

 

[amassi]

Where are you located? If near Sacramento I have a chrono you can use. If not, go to your nearest national forest and bust some rocks to verify your drops. You may also consider going with a mpbr zero instead of dialing since your missing vital inputs

Sent from my SM-G892A using Tapatalk

 

[AkMtnRunner]

Personally, I wouldn't aim at an animal more than about ~100yds farther than what I have verified with actual trajectory. Chronos can be off and BC's can be full of BS. After 100 yards beyond that verification point, the errors can be big enough to wound and lose an animal.

 

[pattimusprime22]

Where are you located? If near Sacramento I have a chrono you can use. If not, go to your nearest national forest and bust some rocks to verify your drops. You may also consider going with a mpbr zero instead of dialing since your missing vital inputs

Sent from my SM-G892A using Tapatalk

I'm in the Bay Area. The only place I've gone to shoot out at range was Panoche Hills and that was bulk ammo (not the brand I'll be using on my hunt), and it's under fire restriction now so no target shooting. I'll check around for national forest area I can shoot. Any recommendations?

 

[pattimusprime22]

Personally, I wouldn't aim at an animal more than about ~100yds farther than what I have verified with actual trajectory. Chronos can be off and BC's can be full of BS. After 100 yards beyond that verification point, the errors can be big enough to wound and lose an animal.

Okay, so the estimating velocity is a no go. I'll try to figure out someplace to shoot at range to validate dope before my trip. Should be able to squeeze in one day somewhere before I leave and if not, then find some place en route to CO.

 

[amassi]

I'm in the Bay Area. The only place I've gone to shoot out at range was Panoche Hills and that was bulk ammo (not the brand I'll be using on my hunt), and it's under fire restriction now so no target shooting. I'll check around for national forest area I can shoot. Any recommendations?

If schedule allows take a day and head up to sac valley shooting center. Get a solid 300÷/- yard zero and have fun in colorado. Take next year to figure out dope for that rifle and get some serious trigger time.
Most of the sierra mountain range is public and plenty of large rocks that want to be smaller rocks

Sent from my SM-G892A using Tapatalk

 

[Gunnersdad49]

What part of Colorado are you heading to?

 

[Reburn]

In my opinion you're walking a dangerous line using an estimate to build a dope chart and in turn hope that minute of critter is good enough.

I would say your effective range for your coming hunt is out to 225ish yards since that's the furthest you have validated. Good luck.

Please heed this advice. If you have only shot 225 yards please don't go out and poke 300-400 yards. MPBR is a great system and I use it on some of my guns. But there is no replacement for practicing at the ranges you would like to shoot at.

 

[wildcat33]

https://cpw.state.co.us/thingstodo/Pages/ShootingRanges.aspx

 

[pattimusprime22]

Please heed this advice. If you have only shot 225 yards please don't go out and poke 300-400 yards. MPBR is a great system and I use it on some of my guns. But there is no replacement for practicing at the ranges you would like to shoot at.

Will do! Currently convincing the significant other that I'll be gone shooting again this weekend

 

[pattimusprime22]

What part of Colorado are you heading to?

Heading to Southeastern CO. Shot in the dark tag application as this was my first year applying in CO, but drew units 120, 121, 125, 126. Doesn't seem like the BEST unit in terms of available public land, however it's a hunting trip so I'm happy to be getting out there!

 

[Gunnersdad49]

Copy. If you were passing through the front range, I was going to offer up a chrono and some range time.

 

[deerkiller]

I know time can be a valuable commodity but busting rocks isn't going to tell you what you need to know as you extend your ranges - you need to know your ranges, 100, 200, 300, 400 on paper to KNOW what your trajectories are then establish a repeatable aim point in YOUR scope picture - antelope aren't very large making the error margin that much more important - limiting yourself to 225 is good advice, wary goats will often draw their line at around 300 (how they know I'll never understand) so don't put too much expectation on your distance, pay at least SOME attention to terrain and antelope weaknesses (CURIOSITY) If you get them running it's a recipe for disaster, they run ALOT but they don't go far normally - also keep in mind that prone shooting in the prairie grass doesn't work too well, practice bipod or sticks kneeling or sitting back on one leg
Antelope hunting is a kick in the ass, enjoy THE HUNT ….

 

[wildcat33]

Heading to Southeastern CO. Shot in the dark tag application as this was my first year applying in CO, but drew units 120, 121, 125, 126. Doesn't seem like the BEST unit in terms of available public land, however it's a hunting trip so I'm happy to be getting out there!

Best of luck. VERY limited access out there. You will get a good taste of how much state owned (public) land is not open to the public, but that's a different thread....

 

[jolemons]

Don't shoot further than you have validated and proven to be competent; it's not fair to the animal.

Sent from my SM-G960U using Tapatalk

 

[Mulyhuntr]

What type of scope do you have? If it has turrets that you can dial, you can get a really good estimate of velocity by zeroing at 100 and then figuring out how many mils/moa it takes to hit at a further distance.

If it doesn't have turrets that you can dial, just zero the rifle at 225 yards and then you'll be a dead on hold out to 250 and ~6" low at 300.

 

[deerkiller]

What type of scope do you have? If it has turrets that you can dial, you can get a really good estimate of velocity by zeroing at 100 and then figuring out how many mils/moa it takes to hit at a further distance.

If it doesn't have turrets that you can dial, just zero the rifle at 225 yards and then you'll be a dead on hold out to 250 and ~6" low at 300.

why not a 300 yd zero then ?

 

[Mulyhuntr]

why not a 300 yd zero then ?

Then you'd be ~5.5" high at 125 to 200 yards, which is too much imo. With a 225 yard zero, you're only 2.5" high at those distances, so you can still hold dead on, but just have to hold slightly high at 300.