Long range big bore

[ccarson2]

Something i have always wondered about and havent been able to test yet, you can see online firearms like a 458 socom shooting subsonic 600 yards plus for deer hunting and dropping deer on the spot.

Wouldnt this be possible for a big bore airgun? People shoot subsonic 457 300gr projectiles accurately long rang at 800 fps from powder burners, whats the difference for an airgun? Is it just a quality issue?
What reason would essentially the same projectile going the same speed be accurate with powder caused expanding gas and not behave the same for hpa?

Pic for entertainment purposes

 

[iAMzehTOASTY1]

Key: shot placement
If you have put one in the ticker or the thinker; you are golden

 

[RM.510bigbore]

I watched that Long range deer kill on YouTube too. They were using and promoting ATN with laser range finder calibrated ballistic. Most all long range subsonic shooting is done with coldshot adjustable base because of the huge amount of moa or mil adjustment. Point being how much adjustment can be used on a ATN digital scope with automatic ballistic calibration. So I'm really sceptical of that video.... I have some experience slinging some lead long range with my 50 Texan...Its extremely challenging will so much drop...A Texan 50 with 4500 psi African Air Ordinance Upgrade will shoot 650 grains at over 900 fps in 34 inch barrel.

 

[ccarson2]

I watched that Long range deer kill on YouTube too. They were using and promoting ATN with laser range finder calibrated ballistic. Most all long range subsonic shooting is done with coldshot adjustable base because of the huge amount of moa or mil adjustment. Point being how much adjustment can be used on a ATN digital scope with automatic ballistic calibration. So I'm really sceptical of that video.... I have some experience slinging some lead long range with my 50 Texan...Its extremely challenging will so much drop...A Texan 50 with 4500 psi African Air Ordinance Upgrade will shoot 650 grains at over 900 fps in 34 inch barrel.

I have the atn 4k pro and the thor 4. I know with the calculator turned on and the data for my 357 rattler punched in it does give me a holdover point. From center crosshairs to bottom mil it has 144 mils on the reticle of my thor 4. Thats at 1 x magnification, when you zoom in you lose some of the bottom reticle.

But with a fx hybrid going 1050fps and a zero of 40 yards it has me holding 550 inches up, which ends up being less than a quarter of the reticle. The furthest ive shot it was 300 yards with the rattler and it was on target.

Cognitively i don't see why they shouldnt be somewhat decent?

For example this guy is shooting 900 fps. 220grain 300 blackout from a 9 inch barrel and a 10 power scope out to 600 and still getting good hit rate.

 

[RM.510bigbore]

There are many videos of long range target shooting out to 1200 yards up north air gunner and the best very big rifle on YouTube. If you have 144 mils you are golden. I figured adjustments on the screen would be limited like regular for scope most having 10 to 12 mils in recticle.

 

[RM.510bigbore]

Yes ballistics the same with African Air Ordinance 4500 psi upgrade in 30 Texan will shoot 230 at over 900 fps..the lee 230 grain vld has a .630 b.c.. The big 50 with upgrade is at 900+fps with 650 spire point boat tail .5 b.c. These valve's are safe with helium too. A booster pump is needed for 4500 psi big bores. Helium would get another 30% faster. So the 50 with a 650 grain has 1000 foot pounds of energy at 300 yards. So 1200 fps with a 650 grain is pretty sufficient with .5 b.c. I would say a custom real bench rest barrel needed Benchmark Krieger Hart Grid etc.. At minimum hand lapped factory barrel. My optical setup with 144 mils dialed in...

 

[ccarson2]

Yes ballistics the same with African Air Ordinance 4500 psi upgrade in 30 Texan will shoot 230 at over 900 fps..the lee 230 grain vld has a .630 b.c.. The big 50 with upgrade is at 900+fps with 650 spire point boat tail .5 b.c. These valve's are safe with helium too. A booster pump is needed for 4500 psi big bores. Helium would get another 30% faster. So the 50 with a 650 grain has 1000 foot pounds of energy at 300 yards. So 1200 fps with a 650 grain is pretty sufficient with .5 b.c. I would say a custom real bench rest barrel needed Benchmark Krieger Hart Grid etc.. At minimum hand lapped factory barrel. My optical setup with 144 mils dialed in..

336 yard shot today with .357 texan, shooting 174gr higharc hunters at 880fps

 

[ccarson2]

3 shot group at 150 yards

 

[RM.510bigbore]

Wow cool...I'm impressed with the atn ballistic software.....300 yards is tough with airgun... Thanks for making a video..... You could.see your bullet impact pretty easily at 330 yards with the .357

 

[steve123]

I have the atn 4k pro and the thor 4. I know with the calculator turned on and the data for my 357 rattler punched in it does give me a holdover point. From center crosshairs to bottom mil it has 144 mils on the reticle of my thor 4. Thats at 1 x magnification, when you zoom in you lose some of the bottom reticle.

But with a fx hybrid going 1050fps and a zero of 40 yards it has me holding 550 inches up, which ends up being less than a quarter of the reticle. The furthest ive shot it was 300 yards with the rattler and it was on target.

Cognitively i don't see why they shouldnt be somewhat decent?

For example this guy is shooting 900 fps. 220grain 300 blackout from a 9 inch barrel and a 10 power scope out to 600 and still getting good hit rate.

I experimented with 300BO for about a year with lots of long range involved.
It was a cartridge that intrigued me at first but I learned that it wasn't something I desired to stay with.

I tried to find a load with lower ES in the subsonic but it seemed that bullet friction?? would destroy the vertical at distance. I tried a half dozen different heavy copper jacketed bullets including Berger 230's, Hornady 225's, and others as light as 155gr all going subsonic. For me this is what happened. Out to 300Y I could stay on the steel which was also a 2/3 IPSC, past that things became much more inconsistent the farther out I went.

With the lighter copper jacketed bullets it wasn't much different going 2000-ish fps. Better vertical than subs but they also blew a lot in the wind.

What made me get discouraged was my friends with their 45-70 Buffalo guns using 535gr lead bullets and black powder at 1200 fps had way less vertical than I did at long range, specifically at 500M, LOL!! Going into our informal contest I thought I would come out ahead, nope not even close.

So there may be something to using lead bullets at subsonic velocities but that's just a guess.

Trying a powerful pcp like the ones mentioned would be interesting for me for sure.