300 blk vs .308

[cmac]

Dang. I have "buy a gun fever" again. This time looking for a medium range, up to 300 yards, bolt action precision rifle that I can suppress really well. Not so precise as trying to win matches, but to get a tight group within 75-300 yards. I already have a suppressed 300 blk in an AR platform, with the Omega, for up close, and a 700 Rem Mag, for long range (not supressed). And, I already a have reloading setup for 300 blk.

My two biggest questions are:
1) is the 300 blk really accurate out to 300 yards, using 210+ grain bullets?
2) is a .308 quiet with a suppressor (Omega)?
Thanks for your thoughts.

[whiterussian1974]

300 BLK: If you mean accurate as in repeatable, then yes.
However, since it is moving slower; wind and gravity have longer to act on it.

.308 Win: Supersonic bullets aren't nearly as quiet as subs. Mine sounds like a car door slamming shut even w earplugs. IE: no less than 138dB. You can get as low as 120-122dB with subs. (Theorhetically you could get down to 95dB or less, but practicality intervenes and size/weight limit suppression w standard loads.)

Why not just thread your 7mm and call it good? Or go for REAL longe range? (600m-1km w/ 6.5 Creedmore or .338 NormaMag)

[cmac]

whiterussian1974 how far out would you say your 300 blk with 210+ gr bullets, is repeatable?

[whiterussian1974]

I don't actually have one. I was going off of published tables in magazine articles and books.
Just wanted to give you an answer b/c sometimes people get discouraged when noone answers for several days, if ever.

[whiterussian1974]

W a solid action, excellent broken in barrel around 100-500rds and a developed load; .250MOA is achievable by the best out to 1/4mi. So 50-300m should be cake.

[cmac]

True. What you said though sounds correct. If anyone has a 10.5 barrel on a 300 blk, feel free to post how far out your rifle is really accurate.

[tsands974]

I have made several consecutive hits at 700m with my AAC 9" upper. It's obviously not designed for that range, as the groups are pretty spread out at that distance and energy is depleted, but it is possible.

[doubloon]

... and energy is depleted, ...

I would venture a guess that a hit on a soft target at that range would not go unnoticed?

[RJT]

If the wind is right, and I mean really right, I can wring out just under 2 moa with my .308 subs at 300 meters. I don't see 300BO being any different out of a bolt gun.

[whiterussian1974]

The 300 AAC Blackout Low Visibility Carbine by Robert S Silvers,
http://300aacblackout.com/resources/300-blk.pdf
Pg 10 states- "1–3MOA at 100M"
Pg 17 shows group sizes
These are for semi-ARs. So probably what your current rig is capable of. Not much reason to get a dedicated 300BLK bolt it seems.

[tsands974]

... and energy is depleted, ...

I would venture a guess that a hit on a soft target at that range would not go unnoticed?

I call about 200 ft lbs of energy at 700m pretty depleted, but I still wouldn't want to get hit by it.

[DKDravis]

My suppressed .308W uses an old Mauser 98 Action and an old target barrel cut down to 18" ..

I shoot subs in that, using Lapua 200 grain FMJ .. my best 200 meter groups with that rig and the subs are around 1,5 MOA --

When shooting the right "full power" load (168 SMK) I get 1/4 MOA -- Same rig and same ASE-UTRA Can ..

A friend has an AAC AR in 300BLK... He can not get much better than 3MOA at 200 m.

I would think that a dedicated short action bolt rifle (Like my Brno 525, which was originally .222) with a good quality 1:7 twist barrel would do quite a lot better using some of the heavier bullet sub loads --

[doubloon]

...
I call about 200 ft lbs of energy at 700m pretty depleted, but I still wouldn't want to get hit by it.

eh ... comparable to a fast moving 22lr so definitely an annoyance.

[TROOPER]

...
I call about 200 ft lbs of energy at 700m pretty depleted, but I still wouldn't want to get hit by it.

eh ... comparable to a fast moving 22lr so definitely an annoyance.

That'll blow your head clean off!

Sorry. I've been talking to a guy recently who bought a 357 Magnum because, and I quote, "If I shoot someone in the head it'll blow them in half!" I asked him if he meant a headshot would split someone equally into left and right halves, but he wasn't amused. I was amused, but apparently that's not always the standard for funny.

Sorry to derail, but the measures for energy on target reminded me of that conversation. It also reminds of a youtube video where a guy was making a case for 45 (over 9mm, I think) based on the longest sniper kill in history. Apparently he calculated the energy of the 338 LM at that range, saw that it dropped a guy instantly, and therefore.... wait for it.... waaaaaaaiit for it.... A 45 WILL ALSO INSTANTLY DROP A MAN!

Science, bitch!

I love everything and everyone.

[whiterussian1974]

... "If I shoot someone in the head it'll blow them in half!" I asked him if he meant a headshot would split someone equally into left and right halves, but he wasn't amused. I was amused, but apparently that's not always the standard for funny.

... a guy was making a case for 45 (over 9mm, I think) based on the longest sniper kill in history. Apparently he calculated the energy of the 338 LM at that range, saw that it dropped a guy instantly, and therefore.... wait for it.... waaaaaaaiit for it.... A 45 WILL ALSO INSTANTLY DROP A MAN!

Science, bitch!

My first mental image was everything above the belt turning to pink mist.
Totally unrealistic.
Then I saw him running head-on into the edge of a sheet of glass; and left/right splitting like Sci-Fi movies. Too funny!!!
---
.22lr @100m into left eye cavity vs. .308 to my pinky toe? All about shot placement.

[doubloon]

...
Science, bitch!
...

I hate it when I get scienced.

There is no arguing logic with a man holding a boner-fyed manstopper like the 45. The 45 killed more men in the Pacific theater than Hillary Clinton in Benghazi.

I've read somewhere that over 300 fl-lbs is required for enough penetration to get the job once and done but I don't think Bill was ever that tall or that fat and he didn't have any penetration problems back in the day.

And if people really wanted to stop drunk driving they'd get rid of parking at bars.

[JeffWard]

How much suppression do you need?

Assuming you're talking shooting sub-sonic suppressed, then there is ZERO difference between a 308 and a 300. They're both launching the same bullet at the same velocity.

If you go supersonic in the 308, it still suppresses well. Mine is a 16" Howa Targetmaster. It sounds like a 22LR shooting 175gr SMK at over 2500FPS. And it shoots inside 3/4" when I do my part with factory ammo.

JeffWard

[TROOPER]

How much suppression do you need?

Assuming you're talking shooting sub-sonic suppressed, then there is ZERO difference between a 308 and a 300. They're both launching the same bullet at the same velocity.

If you go supersonic in the 308, it still suppresses well. Mine is a 16" Howa Targetmaster. It sounds like a 22LR shooting 175gr SMK at over 2500FPS. And it shoots inside 3/4" when I do my part with factory ammo.

JeffWard

The only thing I'd add to the above is that it's not common to see subsonic 308 as a factory loading, and even the handloaders don't get their subsonic at 220 grains since most factory barrels won't stabilize that. Meaning that subsonic 220 grain 300 blk will outperform 308 subsonic in 180 grain.

I don't do either of those cartridges, so it's possible that I'm wrong about the heaviest 308s and their stabilization from a normal factory barrel.

[Joker31D]

My 10.5 is Accurate to about 150m after that, its lost some energy and I dont feel its able to drop an animal, much less god forbid a human being. The 220gr factory stuff I am using is decent but my handloads are better. I use a red dot and a magnifier if its over 100m, dot if under 100 My skill level allows me more room than the other guys I hunt with (Not bragging by any stretch but I have a lot of training) They use a 16" to the same 150m mark with a 3-9X with good results. it does depend on the barrel a lot and of course your comfort level behind the trigger, you have to live with your shots, not anyone else. If you wound an animal and it runs are you ok with it? When in doubt try it on a Hog (our Deer Camp motto)

I never understood this:
a 30 cal bullet (200gr) moving 1100fps is acceptable for shooting deer/hogs but...
a 45ACP +P (200gr) moving at 1100 isnt

Never made sense to me at all.

[TROOPER]

I never understood this:
a 30 cal bullet (200gr) moving 1100fps is acceptable for shooting deer/hogs but...
a 45ACP +P (200gr) moving at 1100 isnt

Never made sense to me at all.

Sectional density. If you wanted to throw a coin into a block of ballistic gel, would you try to throw it in flat .... or edge-wise? Same weight, both thrown as hard as you can, but one will penetrate more than the other. Sectional density.

It's misleading to think simply in terms of "power on target". What are you really shooting at? The deer? Or the deer's vitals? One has 300 hundred feet of air protecting it... the other has 300 feet of air, some hide, some muzzle, some bone, some fluid.... penetration matters.

[whiterussian1974]

It's misleading to think simply in terms of "power on target". What are you really shooting at? The deer? Or the deer's vitals? One has 300 hundred feet of air protecting it... the other has 300 feet of air, some hide, some muzzle, some bone, some fluid.... penetration matters.

He means "muscle."

[RJT]

Expansion is the key, plain and simple. Regular rifle bullets will not expand at subsonic velocities.

[Joker31D]

the difference in sectional density .140 vs 300 should be somewhat compensated by the diameter of the bullet. I know its a complicated trig question and the factors are infinite but there should be very little difference considering the fact that most people accept the 357 magnum as acceptable on small deer and at one point in our history it was thought to be too much gun for LEO's. I'm not advocating small caliber pistols for hunting, just proposing the question as a ballistics exercise. I personally have used 357 as personal protection in the field and dropped 2 charging hogs but only because I had left the rifle in the swamp buggy. I now carry a 10mm because I hunt sometimes in my wheelchair when my body doesnt cooperate and have seen aggressive bears in the field. one of which was in the mood for a doe I shot and I wasnt going to fight him for it. I backed out slowly and let him have that section of woods. later it was killed by a Game warden who was checking a game camera for poachers with a 9mm (34 rounds of Winchester SXT's) I didnt see it but he quit a month later after he shot it and his replacement told me. He told me that he shot it with 2 whole mags then had to beat it with his ASP to kill it. Thats what made me switch to 10mm.

[JeffWard]

Expansion is the key, plain and simple. Regular rifle bullets will not expand at subsonic velocities.

http://www.blackoutbullets.com/
http://www.lehighdefense.com/products/3 ... 1073832868
http://outlawstatebullets.com/2.html
http://www.makerbullets.com/proddetail. ... 308200SBLK

All expand reliably at subsonic velocity... Bullet design for the 300BLK has come a LONG way.

JeffWard

[DKDravis]

Yup -- Science is an annoying intrusion into our firearms fantasies ...

The difference between an 230 FMJ 45ACP close up, and the 338LM 300 grainer at a mile, is "SD" or "Sectional density" --

Put simply the .338 -300 grn has 300 grains to push a significantly smaller area (pointed too!!) through some(ones/things) skull than the roundnosed 230 grn 45ACP ..

I just did the test ... in soaking wet phonebooks .. (poor mans ballistic gel .. ) a subsonic 300 grain .338 Lapua Scenar went completely through the small stack .. 55 cm (1.5 ft) even though it tumbled part way through!! The 230 grn FMJ 45 ACP stopped in the last phonebook .. so did only just over a foot ..

Expansion is the key to a quick kill on smaller animals, when using subs ... no doubt .. but larger animals require that the bullet makes it to, and through vital organs .. This is the same for any velocity bullet .. So: to ensure a positive (maybe not dropped on the spot) kill, the bullet has to penetrate deeply enough and make sufficiently large holes in vital organs ..

The whole "energy on/in target" becomes a question of MASS when shooting SUBS ... since the bullets are all travelling at speeds below 1000 - 1100 fps.
950 fps is still enough to cause a lot of damage from a sufficiently heavy and readily expanding bullet, like the ones for .300BLK ..

But: If you have a .300BLK 210 grain bullet leaving the muzzle at 1050 fps .. then you have to compromise between a good BC to keep the velocity from dropping too fast and a shape and construction of the bullet that promotes good subsonic expansion .. those two factors WILL be opposing each other .. In total this limits the distance at which a subsonic round is feasible as having a good expansion ..

I have just recently shot two roe deer (just under 50 lbs live weight ) using my .376Steyr.. one was shot with a 300 grain Sub-load using a plain Hornady SP-- lung hit, through & through .. broken ribs on both sides .. dropped on the spot .. No sign of significant bullet expansion...!
Number 2. roe deer: shot with the same rig, but with a 250 grain Barnes TTSX at 2700fps+ Same shot placement ... the roe deer ran more than 60 meters (180 feet) ... Textbook "Barnes-X" star expansion with the characteristic "square" exit wound ...
deer do NOT always react according to "science" ..

I have worked extensively with trying to create good consistent subsonic rounds for the .338LM .. for use in the standard 1:10" twist 20-something" long barrels used by military snipers ..
I have been able to get very good results with modified cases and Trailboss and VV "Tinstar" powders .. but the twist-rate is a limiting factor, as is the expansion properties of the heavy .338 bullets with a good BC ..