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schambers
25 January 2016, 18:55
I've been playing with the idea of putting together a 300BLK bolt gun and am curious to know if the juice would really be worth the squeeze.

Right now I'm thinking of using a 16" barrel, suppressed. I'm trying to be realistic here so I don't expect to push farther than 500m... Although that would be nice.

I've been trying to find some solid data for ballistic coefficients, wind drift data, drop characteristics and energy retention on the 300BLK at 400-600m.

So far I'm having trouble finding info beyond anecdotal evidence and I'm assuming I'm having a hard time because of the wide variety of loads available for the round. Maybe I'm just looking in the wrong places.

Anybody here have the kind of info I'm looking for, or can point me in the right direction?

alamo5000
25 January 2016, 19:29
The main question I have is 'why'? Why 300BO? Especially trying to reach out to 500m... You won't have any extra suppression just because it's 300...not if you are shooting supers...

If you want the information though you can easily go extract what you want from hornaday's website. Look up all the 300 blackout cartridges they have, get the velocities, ballistics coefficients, and grain weights and plug them in to the calculator...That will give you a general idea...

http://www.hornady.com/store/300-Whisper

and the calculator is here:

http://www.hornady.com/ballistics-resource/ballistics-calculator

I plugged in the data for the 300 BO 208 grain sub that was shot out of a 16" barrel and at 500 yards there was a 71 MOA correction. That is pretty insane... you would need one hell of a scope to get there with that. The drop would be 31 FEET at 500 yards with that round...I've done many shots that had more than 30 feet of drop... but they were out to 800 or 1000 yards or whatever....

You can mix and match and see what you get though....use the basic and the advanced functions if you want to get into it and start figuring out windage and all that...

alamo5000
25 January 2016, 19:48
Just for comparison purposes 71 MOA is the same correction you would use for a .338 Lapua with a 285 grain match bullet to shoot an actual mile. 1760 yards....

schambers
25 January 2016, 19:59
The main question I have is 'why'? Why 300BO? Especially trying to reach out to 500m... You won't have any extra suppression just because it's 300...not if you are shooting supers...

Mostly as something to mess around with. No practical purpose really. Again, just trying to gather data to see if the project is something really worth pursuing.

The drop is a lot more drastic than I thought it would be. Going to dig into the Horniday site a little more to see what I can get from there

BoilerUp
25 January 2016, 22:24
You're asking a shepherd to retrieve. A bolt action in 300 BLK would make for fun little ranch gun or trainer for a young shooter, but putting holes in things out to 600 is asking a bit much, IMO. You CAN do it, but why would you? Bullet drop aside, there isn't much steam left in the 300 BLK past 350 yards. The 300 BLK was designed to achieve an objective within the constraints of the AR platform. Once you move to a bolt, those constraints don't apply.

I just pulled up the Barnes 300 BLK 110gr Tac-Tx round in the Swarovski ballistics program for the scope I use on my 6.8 SPC hunting rifle. With that round at 10x magnification, I run out of holdover on the reticle (15 MOA) at 434 yards.

That said, I think Ruger's American Ranch in 300 BLK would be a fun little rifle that I wouldn't hesitate to take deer hunting and use for shots within 200 yards.