300 Blackout Bullet Selection

[BSDJoker]

Hello,

My first time posting on here. I tried looking through the forums to get some insight on this, but wasn't able to find anything quite like what I'm looking for. I'm new to reloading. I have the gear and have mt first 100 cases sized, trimmed, swaged, and thoroughly prepped. Now, I'm down to selecting what bullet I want to use for the loads and I've been trying to do my research on this.

My firearm is a 16" Anderson Arms 1:8 twist w/ pistol length gas. Non-suppressed, as Illinois still sucks about that. I'm running a nice Kinetitech brake, though. So, I'm sticking to supersonic loads for now. l plan to use Lil'Gun powder for my ammo. My question is...

With the research I was doing, I came across some calculations that I want to ensure that I'm reading right.

I was comparing 125gr or 150gr SMK HPBT to see which one I wanted to use. With the ballistic calculators I'm using, I'm seeing higher ft lb energy over distance from the 125gr than the 150gr bullets. Now these are almost max loads that I'm using as a basis, but I'm just using it for starting math.

125gr: 2375 FPS @ 1566 ft lb muzzle velocity / 1714 FPS @ 815ft lb @300yrd
150gr: 2000 FPS @ 1332 ft lb muzzle velocity / 1447 FPS @ 698 ft lb @300yrd

Now, I'm curious... because the additional mass from the 150gr, even with a lower ft lb energy would mean that it's still hitting as hard, or harder than, the 125gr bullet, correct?

Now, as I said, I'm new to this, and I know I'm going to have to do batch testing with my own chronograph and targets to get actually test things, and it's not really a big deal, as I'm going to be target shooting with this. But, if I'm loading ammo for a SHTF situation for protection and all that good stuff, which one would be the better round? Or are there any other recommendations or things that I'm not thinking of at the moment. I would appreciate any help on this.

Thank you,
Joker

[disseminator]

Consider the following bullet data I grabbed from Hodgdon:



Using these bullets for comparison I can see why it would seem as though the heavier bullet should have more energy but the answer is that it does not. The 125 Ballistic Tip is one of if not the best Hunting bullets for 300bo IMO and this data shows us why.

Using maximum loads, the 125 BT is reaching 2400 fps from the 16" barreled ar15. I have shot this load in my 300 many times and its a good accurate load and was 100% reliable for me.

@2400 fps we are developing about 1600 lb ft of energy at the muzzle.

@200 yards, were down to 1060#' and @300 yards, 848lb ft.

Contrast this to the 150 grain Hornady Interbond. Nevermind the terminal ballistic which are inferior in the 300 blk vs the 125 BT.

Using the maximum load we are seeing about 2062 fps at the muzzle and around 1422 ft lb of energy.

@200 yards, were down to 962 ft lb, and at 300 we are down to 785.

So in this case the 150 IB is not up to the same performance of the 125 BT even though it has an advantage of .415 vs .366 in the ballistic coefficient.

No 300 blackout is suitable for hunting IMO beyond 300 yards.

As time goes on, we will probably see more emphasis on terminal performance in bullets designed specifically for the 300bo. Until then, we'll get by.

Hope that answers your questions. And btw, I got a deal on 1000 150 Speer SP a while back really cheap from Midway USA and have been shooting them around 2000 fps and they are excellent for shooting, but I'd never hunt with them.

@

[Jimro]

Now, as I said, I'm new to this, and I know I'm going to have to do batch testing with my own chronograph and targets to get actually test things, and it's not really a big deal, as I'm going to be target shooting with this. But, if I'm loading ammo for a SHTF situation for protection and all that good stuff, which one would be the better round? Or are there any other recommendations or things that I'm not thinking of at the moment. I would appreciate any help on this.

We don't do SHTF here.

All bullets are lethal. The difference in terminal effects is at best, a measure of time for bleeding out for a "normal" hunting shot, and central nervous system hits will have identical effects.

The 300 BO doesn't have the energy to make a bullet fail on impact, so you penetration isn't a concern. Expansion is, as the BO has a pretty narrow impact velocity window with "normal" hunting bullets, which is why you see so many 110 to 125gr bullets marketed at the BO now.

So...load what you like to shoot. Your target loads are going to be "plenty lethal" if you need to use them for something other than target shooting.

Jimro

[Mobuck]

"Now, I'm curious... because the additional mass from the 150gr, even with a lower ft lb energy would mean that it's still hitting as hard, or harder than, the 125gr bullet, correct?"
I'd suggest you pay more attention to bullet effectiveness vs "paper" ballistics. Energy doesn't mean a whole lot if the bullet whizzes through headed for the next zipcode.

[rg1]

Don't think you'll be able to achieve 2375 with a 125 gr. At least my loads started to show high pressure going higher but that's with H110 powder. More likely in the 2150-2175 fps. Probably 150 gr. loads around 1950 and possibly 2000 fps. I load 147 gr. M80 FMJ's for a good plinking load. My favorite load for supersonic is Hornady's 110 gr V-Max. I'd choose Nosler's 125 gr. Ballistic Tip for your hunting, plinking, target loads. The 147 gr. FMJ's shoot well for me and can be found much cheaper than most 150 gr. premium bullets. Lot's shoot the Hornady 150 FMJ which can be bought in bulk. Some advice I've seen is H110/Win 296 works well for 110 to 150 grains and Lil Gun is better for 150 gr. and higher for supersonic loads.
Hodgdon says 125 gr. BT with Lil Gun 16.9 gr--2086 fps Maximum 18.0 gr--at 2185 fps. Rem case, Rem RP 7 1/2 primer. Oal with 125 BT as tested was 2.060". Hodgdon tested in a 1/8 16" barrel.
Using H110 or Win 296 Hodgdon says 16.7-2020 and 17.8 maximum for 2118 fps. I load 17.5 grains and get 2155 fps in my 16" AR 300 BLK.
You also have to look at the velocity that the bullet is recommended for. For instance Hornady says their 125 SST (also a great choice for BLK) is designed for 2400-3200 FPS while the 150 gr SST is designed for 2700-3600 fps the same as the Hornady 150 IB bullet. For reliable performance with expansion and penetration.
Hornady's max data with Lil Gun or H110/ Win 296 only gets 2000-2100 fps with 125 gr. bullets. I would test Hornady's 125 gr. SST bullets in your BLK. My data comes from Hornady 10th Manual and Hodgdon's 2017 Annual Manual. I do see on the Hodgdon web site they have higher maximums but be cautious and work up. Don't start at maximum.

[Chainsaw.]

Run what works best for you/your rifle. All the ballistic tests in the world to eek out a few more Lb/ft doesn't hardly mean squat when applied in an "OH #@$¥*#" situation.

[superspirit]

I've had awesome luck with the hornady 125 SST in my 300blk. Cant access my my load book right now, but I believe I'm running real close to the max of lil gun. Been very accurate with great terminal performance. Atleast on south Texas whitetail.