300 blk vs .308

[doubloon]

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

Looks like serviceable expansion out to around 150 yds.

[whiterussian1974]

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

Yes! The key is minimal frontal area and high BC until reaching the critical "vitals" section. Then and only then, MASSIVE upset via expansion/fragmentation/separation/tumbling.

Hitting a shoulder/rib/spine is a great way to limit movement and cause organ damage.

For humans I have long advocated a pelvic pt of aim for criminals holding edged/blunt weapons at close range. (Tueller Drill.) Much better than a head shot and often no kevlar in the way. (Also covered by Massad Ayoob in a Shooting Times article.)

Marshall, Evan; Sanow, Edwin (May 1, 1996). Street Stoppers: The Latest Handgun Stopping Power Street Results. Paladin Press. p. 142. ISBN 0873648722
This is why I switched from a 9mm SW369 to a .40SW Glock22. And loved it ever since for several other reasons. Weight, recoil, simple operation, easy disassembly, few parts, easy to aftermarket customize.

[JeffWard]

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

Yes! The key is minimal frontal area and high BC until reaching the critical "vitals" section. Then and only then, MASSIVE upset via expansion/fragmentation/separation/tumbling.

Hitting a shoulder/rib/spine is a great way to limit movement and cause organ damage.

For humans I have long advocated a pelvic pt of aim for criminals holding edged/blunt weapons at close range. (Tueller Drill.) Much better than a head shot and often no kevlar in the way. (Also covered by Massad Ayoob in a Shooting Times article.)

Marshall, Evan; Sanow, Edwin (May 1, 1996). Street Stoppers: The Latest Handgun Stopping Power Street Results. Paladin Press. p. 142. ISBN 0873648722
This is why I switched from a 9mm SW369 to a .40SW Glock22. And loved it ever since for several other reasons. Weight, recoil, simple operation, easy disassembly, few parts, easy to aftermarket customize.

1996 is well before the latest innovations in bullet technology. Modern 9mm will do the job as well as 40 or 45 95+% of the time... but with greater capacity, and faster follow-up shots.

To each their own...

JW

[RJT]

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

Looks like serviceable expansion out to around 150 yds.

I've had good results a little past 100 with outlaw state bullets, but I only have a 308.

[savagetactical]

Go for the 308 and forget about shooting subs at 300m, it would just be too frustrating. 300 blk subs should only be used within 100 yds. The bullet drop is just way too excessive after that. My 300 blackouts sighted in at 100 yds have 100 inches of bullet drop at 300 yds shooting my 220 grain subs. Time of flight also makes it much more susceptible to wind drift. By comparison, my 110 supers launched at 2350 fps sighted in the same distance have only 7" of drop at 200 yds and 24" at 300. My 16" AR308 has approximately half of that drop over those distances shooting a light 130 grain load at 2834 fps. I think you will be happier and have a much more flexible firearm if you go with a 308.

[eastern_hunter]

No magic here. You can't get 308 performance out of the 300 BLK in supersonic mode. You can get 300 BLK perfomance from a 308 in subsonic mode ... in fact you're pretty much limited to that.

In my humble opinion 30 cal subsonic regardless of the chambering is not a 300 yard tool. Drop and wind effects make it quite challenging.

Yes ... I have both ... 300 BLK in SBR and 16" rifle form, and 308 in AR and bolt rifle form. All suppressed.

Have killed deer with subsonic 300 BLK but at ranges under abt 100 yards. Have used the 308 at much longer ranges in supersonic mode.

[Capt. Link.]

Most of my experience in 30 caliber is the 7.62x51 which is very capable with super sonic loads.I also have a 300 whisper that can shoot the nuts off a squirrel at 300 yd with 240 gr SMK bullets.The original spec was full penetration on both sides of a Kevlar helmet at 300meters suppressed with these 250 and now 240gr match bullets.JD Jones was getting .25 moa or less out of short barreled M-16s years and years ago.These heavy loads are very precise and optics can be tuned to its rainbow trajectory.They don't get blown off course as much as lighter bullets either.You just can't get your average .308 to shoot a 240 match bullet with the standard twist rates of 1-10 to 1-12 with any accuracy.I could see major damage done to a suppressor even trying it.You really can't compare the two only one is quiet and accurate with the heavy bullets you need for deep penetration out to 300M.

-CL

[doubloon]

... You can get 300 BLK perfomance from a 308 in subsonic mode ... ...

Agree with all this other than the nit picking exception of reliably cycling an AR-10ish as far as I know.

If you want that ammo burning, semi-auto pop-pop-pop in a 308 caliber 300BLK gets you there.

There have been a couple people who have posted claims of reliably cycling subsonic 308 in an AR-10ish but I haven't seen it corroborated by a reliable member. I may have missed it so if anyone wants to rub my nose in the proof I would be grateful.

[rimshaker]

Go for the 308 and forget about shooting subs at 300m, it would just be too frustrating. 300 blk subs should only be used within 100 yds. The bullet drop is just way too excessive after that. My 300 blackouts sighted in at 100 yds have 100 inches of bullet drop at 300 yds shooting my 220 grain subs. Time of flight also makes it much more susceptible to wind drift. By comparison, my 110 supers launched at 2350 fps sighted in the same distance have only 7" of drop at 200 yds and 24" at 300. My 16" AR308 has approximately half of that drop over those distances shooting a light 130 grain load at 2834 fps. I think you will be happier and have a much more flexible firearm if you go with a 308.

My thoughts exactly. Except for the last sentence. Have both! Then you won't need 556 whatsoever.

[savagetactical]

My thoughts exactly. Except for the last sentence. Have both! Then you won't need 556 whatsoever.

Having both would be nice (I do) because anything suppressed in a bolt action is awesome. A 16" 300 blk bolt gun is a light, handy little gun to carry plus subs sound like an air rifle through it suppressed. However, If I had to choose one I'd go with 308 since it would give you the most flexibility. Also, the OP said he already had a 300 blk AR and was more interested in a intermediate precision rifle. 308 would fit that bill nicely.