Thoughts on subsonic 300 Blackout for deer hunting

[kselkhunter]

https://www.lehighdefense.com/308-maximum-expansion-194gr-subsonic-bullet

Very interesting -  Not cheap!

Midway carries that Lehigh bullet in loaded ammo from Underwood.  It's in stock, if you didn't want to reload.  They also have in stock the 260gr round nose soft point hunting ammo from Atomic that should work nicely on deer.

[Rob]

I am interested to see the results of this, so if you do end up using your blackout can you please post up some info and pictures?

you bet.

kselkhunter/KFhunter:  those Lehigh bullets are wicked looking.  I may have to play around with those.

[birdshooter1189]

My comparison to the 300 wm was just based on muzzle velocity, bullet weight, and the b.c. listed for the bullet in the first post.  I agree with others that it would not be the bullet of choice for 1100 yd shots.

I generally run 208gr A-max for the winmag and 110 gr z-max for the blackout.  I shoot mostly paper and an occasional coyote and mostly less than 100 yds.

If your primary concern is ricochet's and the bullet carrying far, I fully stand behind the previous comment of a small bullet going fast will be safer than a heavy bullet going slow.  Small bullets going fast break apart/deform and lose energy faster.

If noise (perception of neighbors) is the primary concern, then i'd go with the heavy and ultra fast expanding options that were mentioned. 

[Yondering]

I am interested to see the results of this, so if you do end up using your blackout can you please post up some info and pictures?

you bet.

kselkhunter/KFhunter:  those Lehigh bullets are wicked looking.  I may have to play around with those.

Not cheap, but if you're going to hunt with subsonic 30 cal, that's the bullet to use.

It sounds like there's a significant misunderstanding about heavy subsonics from both the landowner and yourself - a heavy subsonic 30 cal penetrates far FAR more than the same bullet pushed to reasonable hunting rifle velocity. I have some experience with this, and can say for sure that you will absolutely get complete pass through with that 220gr RN on deer from any angle, with the possible exception of a front or rear shot directly into and along the spine. The lack of expansion means very little energy transfer, i.e. not much force acting to slow down the bullet.

Using a non-expanding heavy subsonic (which means pretty much any 30 cal heavy, except those specifically designed for subsonic expansion) gives far more likelihood of excessive penetration, ricochets, and danger to homes than any other bullet or cartridge choice. It is literally the worst option you could possibly choose for that application.

Besides all that, it's a very poor choice for hunting because they do so little damage. If you insist on using them, you should plan on only taking head shots or spine shots. Other than the capability for better accuracy, you're better off using archery than a non-expanding subsonic 30 caliber.

[BULLBLASTER]

I used my google skills and saw that noveske and nosler developed some sub ammo that is supposed to expand to twice its original diameter. It might be worth a try?

This one looks similar but doesn’t have the fancy black paint. Maybe it’s good?

http://www.shootersproshop.com/ssa-300-aac-220-grain-ballistic-tip-round-nose-ammunition-blem-20ct.html

[KFhunter]

subsonics also don't stabilize in flight like a traditional supersonic, so I wouldn't recommend head shots unless you do a lot of work to get them dialed in.
(I still don't recommend head shots)

They're a different beast, so if you're a reloader you'll have to rethink/relearn to shoot small groups while subsonic.

Seems the guys getting the most accuracy are using bolt guns with a small amount of fast burn powder.     

So ya, it seems to be an art to shoot accurate while subsonic

[CP]

@CP

I think CP has done some low velocity testing in this. Not sure ifvhe has put the smack down though.

Yep.  I’ve shot the 220 grain Sierra Gamepro round nose into ballistics gel at 1050 fps and they just zip straight through and keep going.  You would be better off using a supersonic load that expands and stays in the deer, or better yet a shotgun with slugs.

[10mmg]

I took a mulie doe last year from a suppressed 300 blackout at 50 yards using the factory remington 220 grain suns. it was a head shot and she never stood up out of the bed. just an fyi.

[Rob]

Greatly appreciate the input to all who posted here.

I ordered some of the Lehigh bullets and will experiment with them to see if I can get them to shoot.  This will be my preferred bullet if I can get groups.  I did toy with these, but thought heavier would be better: https://www.midwayusa.com/product/1018299340?pid=829338.

Suppressed sub-sonic is a whole new world for sure.

A through and through shot is actually OK with me, if it groups - and at 50 to 75 yards I am happy with 2 MOA for deer.  I have taken 5-6 impala, a vervet, a klipspringer, a mule deer, a hippo, and probably several other animals with solids (large caliber, fast moving of course.)  All were dead in there tracks with pass-throughs and limited internal damage.  The issue comes when you have a poorly placed shot.

My concern was that such a fat slow bullet would not have good penetration but it sounds like I was way off on that.  (this is why I ask lots of questions)

Will be spending Sept and early Oct. looking at load development and then hopefully field testing in late October!  Will post results.

[Yondering]

IMO you should be able to get 2 moa or better with any of the bullets mentioned here.

Fast moving solids are a whole different thing than subsonics; velocity actually does matter and plenty of it makes a solid still effective, especially on large heavy game and if you hit bone. When things slow down to 900-1000 fps with a RN or SP solid, not much damage happens in meat, unless bone is hit to create some secondary wounding fragments. A flat point does a little better, but a 30 cal flat point is still pretty small and does not work as well as a big bore handgun flat point. If you do some careful reading of subsonic 300 Blk hunting accounts, most guys who have success with traditional bullets (non-expanding at subsonic speeds) hit shoulder bone, spine, or head. The few who are willing to admit lost animals usually describe shots into meat and organs without hitting those areas.

You mention a "fat slow bullet", but heavy 30 calibers are not a "fat" bullet; they're thin with a lot of weight behind them, and at low speed there's not much happening in meat to slow them down. Even in wood target backers or live trees, depending on the bullet the penetration is a matter of feet, not inches. A heavy "fat" bullet like a 300 gr .45 for example is a whole different story, with enough frontal area to cause damage and slow down the bullet.

That Lehigh or other bullets designed for subsonic expansion give you a lot more margin for error, better chance at recovering the animal, and a lot less chance of over penetration. This is one area where cast hollow point bullets really shine since it's easier to get expansion with soft lead than with jacketed bullets. If you're not a bullet caster though that may not help, I don't know of a commercial source for any that really work well.

I do fully agree with the other recommendations for a light weight high velocity bullet if you're looking for reduced penetration. Convincing the land owner may be a different story though.

[meatwhack]

The bullets that are designed for subsonic use I’d use in a heart beat. You can kill a deer with a .22 what matters is shot placement. You poke a hole in the heart and that deer is dead.

[Rob]

Some velocity testing I did on the two bullets this weekend. (ignore the subtotals - they are averages and more or less meaningless here)

Looking like 9.3ish grains of Lil Gun will work for the Lehigh's.

[Rob]

I have a little more work to do... 

one more round of testing with the Lehighs to get it closer to 1050, some hotter loads with the Sierras to do the same, and perhaps some hotter loads for my plinker round (the plated bullets)


Then it is on to accuracy verification

Time is ticking!

[Yondering]

Rob, looking at your data, I'd want to use 9-9.1gr of Lil'Gun for about 1,000 fps or a hair less. There is not much ballistic advantage in going up to 1,050 fps, it's usually louder suppressed than 900-1,000 fps, and in cold weather you can still get the beginning of a supersonic crack at 1,050.

If you don't already know - the noise of a supersonic crack doesn't happen at one specific velocity number; it's a gradual range that is roughly between 1,000-1,200 fps where pushing faster makes the crack louder. This varies with temperature of course, in summer time we can push 1,050-1,080 fps fairly quietly, but in winter need to go slower. The sound of the shot is still less at lower velocity anyway. For my quietest subsonics I try to stick to about 900 fps; there is a noticeable difference between that and 1,000 fps. (when shooting suppressed of course)

[Rob]

Interesting -  I had noticed that actually.  when shooting in the 600 to 800 fps range it was very quiet.  minimal difference into the 900's.  once I started hitting 1000 it was definitely getting louder with a noticeable crack staring to form.  by the time I was at 1100 or 1200 it was pretty much there.

updated table with new data points below.  Again, ignore the averages (just a feature of the pivot tables)

Some observations:
-I had two failure to pick up velocity on the plated bullets (the #Div/0! cells).  They sounded sub-sonic though
-oddly my velocities dropped with the Sierra Pro hunter bullets in the 11.7 to 12.3 grain range.  no idea why.   Was also not getting the bolt to lock open at those speeds.  I was pretty careful with my loading and labeling process so I do not think they were mis-labeld or weighed...
-similar situation with the 9.3 and 9.2 grain loads with the Lehigh's  All the other readings are single shot strings - these two were 3 shot averages).  could just be that .1 grains is not enough to make a significant difference in speed for a 194 grain bullet.


Based on your comments, I think I agree... 9.1 grains of Lil Gun on the Lehigh's.  I might do a 9, 9.1, 9.2 and 9.3 load to see if the different charges group differently.