I am debating between a 8-9in barrel 300blk or 9mm carbine for a fun little range toy that would eventually get suppressed. There is no real intended purpose but I would like to have some accuracy (minute of groundhog) out to 50yrds.

Question:
Which one are you picking?

Choices:
300 blk
9mm

 

For ammo prices alone, 9mm. If you reload, it’s still cheaper to work up a quality subsonic 9mm load vs buying factory. A friend of mine has a clean burning load using Vihtavouri power and he said he’s about twelve to fourteen cents a round.

For “eventually” suppressing and “range toy,” I’d say especially 9mm over .300BO.

IMHO, 9mm wins big time from a cost per round perspective, but that’s it. It’ll make a great range toy, but the 300 will eat its lunch from 0-200 yards if you’re using it to hunt or for defense.

I chose 300 Blk for its versatility when I was pondering the same thing. I picked up a used DDM4PDW in 300 a few months back. Turns out I like it even more with Supers than I do with Subs. For me, it’s like having a 7.62x39 in a short barreled AR package that actually works reliably.

Inside of your specifications, the .300 wouldn’t move the needle for me. 9mm will win just about every category.

Mine:

https://share.icloud.com/photo...FEFXYkKFaELi_vfbJsgw

I sold the shorty upper as I was not shooting it much.

I do not shoot as much as I used to with work and my sports car hobby but it is the ultimate toy.

This is a 10” bbl integrally suppressed Colt 9mm AR15 by John Norrell, registered as a SBR and suppressor stamp.

It is the same length as a CAR and if you do not have a SBR with the short bbl, it would be too long and is as quiet as an air gun. I can only hear the bolt cycling.

I have used it w a PVS-14 on the long rail too.

The 32-round Colt pattern mags are good.

Given that you're looking at 50-yard max, a 9mm PCC wins hands down. Cheaper ammo, lower recoil, and likely better accuracy than sub-sonic 300blk. The 9mm actually flies well to 100 yards, even 150 yards with quality barrel & ammo.

From your parameters I think 9mm. But, I love suppressed subsonic 300 Blackout. It is so much fun to shoot and easy to reload. I shoot it out to 200 yards and still can do decent work w/ it. I like 9mm and shoot it a lot but, I think expecting to even come close to a suppressed subsonic 300 BLK. At 200 yards is a pipe dream.

ok so he says out to 50y. so why are we even discussing 300blk???

Yeah, I don’t get it. You guys advocating for .300BO aren’t touching on a single thing the OP said he wanted to use it for, and saying it’s better for everything he didn’t ask about.

quote:

Originally posted by 357fuzz:
From your parameters I think 9mm.

There shouldn't be a question here. 50 yards, plinking -- 9mm PCC it is. No discussions of the kinetic energy for defense or hunting. Just hitting a 50-yard target with reasonable accuracy -- maybe a groundhog.

quote:

Originally posted by 357fuzz:
I like 9mm and shoot it a lot but, I think expecting to even come close to a suppressed subsonic 300 BLK. At 200 yards is a pipe dream.

I disagree. First a little background. Here's my Wilson Combat 300blk SBR. From a Sigforum thread where we rotated among different drills -- using ARs, PCCs, rimfires, pistols.


Here's my Wilson Combat 9mm AR PCC SBR. I've also shot it for the Sigforum drills thread.


Here's a pic of 10 rounds of S&B 115 grain FMJ 9mm from the PCC at 200 yards. Wind blowing hard from the left, and I was holding on the 12" plate's left corner, or a little off plate to the left. The lateral dispersion is primarily due to wind drift. The vertical dispersion of 2.5" is due to system accuracy. That's 1.2 MOA vertical dispersion at 200 yards with cheap-ish FMJ ammo. Yep, 9mm flies just fine to 200 yards -- if the rifle/ammo/sights/shooter are up to the task.


I have attained this level of accuracy with 300blk at 200 yards with quality supersonic ammo. I can't even come close with 300blk subsonic ammo at 200 yards. I find that the heavy subsonic bullets occasionally keyhole on targets at 200 yards, which means they're not flying true, or accurately. When subsonic loads are done in a case with capacity for supersonic loads, the powder in the subsonic load isn't filling the case's volume. The powder could be more toward the rear, centered in the middle, or more towards the front of the case. This is a recipe for inconsistent MV -- which with a subsonic bullet's rainbow-like trajectory, leads to inconsistent vertical dispersion.

I find that subsonic 300blk's heavy bullets buck lateral wind quite well. But they're still not that accurate horizontally. The vertical dispersion is rarely equal to the meager horizontal dispersion on target -- especially from 75-200 yards, where I regularly see verticals that are double that of horizontals. Bottom line -- quality supersonic 300blk loads are at least twice as accurate as quality subsonic rounds -- at that's at only 50 yards.

Now I do get good accuracy from supersonic 300blk rounds with quality bullets, specifically Hornady 110 Vmax and Aussie Outback 125 HPBT. Roughly 1 MOA accuracy, even out to 450 yards, which is the farthest I shot my SBR.

*****
But back to the OP's stated wants:
- fun little range toy
- There is no real intended purpose but I would like to have some accuracy (minute of groundhog) out to 50yrds.
That's 9mm PCC in spades.

I stand corrected. Very nice Fritz. I would never guessed you could do that work at 20 yards w/ a 9mm. Now, to be fair I don’t think a 7.5” (or close to that) AR could do decent work at 200 yards w/ subsonic. But, it is capable in my 16” Ruger American Ranch.

For subsonic range toy I think the answer is 9mm PCC, based on .75 cents vs. 25 cent ammo.

I have an 8.3" and 10.5" 300 Blackouts, and they are a blast to shoot suppressed. I'm glad I have them but the .75 cent per trigger pull adds up fast. I think 300 makes sense if you might also have the occasional use for 110 grain supersonic ammo for hunting or defense. That's the reason to get a 300, it can do both, but ammo is expensive. I'm now looking at getting a PCC for the range to keep ammo costs down.

I have a 300 BO SBR and Ruger Ranch rifle and they are a ton of fun to shoot suppressed and I reload my own subs to make it easier on the wallet. But I shoot my 9mm PCC's suppressed WAY more because 9mm ammo is so much more affordable.

fritz, does 9MM bullet shape and weight affect accuracy at 100 yards and beyond?

quote:

Originally posted by RichardC:
fritz, does 9MM bullet shape and weight affect accuracy at 100 yards and beyond?

Great question, and one that few shooters really test.

Let's start with ballistics coefficients. 9mm bullets don't have the high BCs of match rifle bullets.
- 115 grain FMJ is generally listed around .140 G1
- 124 grain FMJ tends to be around .165
- the 147s are often around .200, and it appears the flat-nosed versions can be similar to the HP versions

From a pure accuracy perspective, FMJ isn't the best. Awhile back, I heard the high-end pistol shooters like Hornady's HAP bullets, as evidently they are quite accurate. But definitely more expensive than FMJ.

So...the heavier bullets buck crosswinds better and the expensive defensive bullets are more accurate in 25-50 yard pistol matches. Honestly, I haven't tested Hornady's defensive 147 grain loads at distance. I suspect they will be quite accurate.

In reality, the FMJ ammo I've tested is definitely accurate enough for my training use with an SBR -- which is generally off-hand and barrier-supported shooting at multiple steel plates at 10-50 yards. The prone accuracy testing reveals that when I'm missing targets, it's not due to the ammo.

quote:

Originally posted by RichardC:
fritz, does 9MM bullet shape and weight affect accuracy at 100 yards and beyond?

I don’t have any personal experience with shooting the 9mm Luger cartridge from longer barrels or at long distances, but one simple ballistic solver comparison is how much wind would affect a 124 grain FMJ bullet with a G1 ballistic coefficient of 0.16 as compared with common 300 Blackout loads. I used the Applied Ballistics solver for the following:

Assuming a muzzle velocity of 1300 feet per second from a 9 inch barrel for the 9mm and a 10 mph full-value (90°) crosswind under “standard” atmospheric conditions, it would be deflected about 17.6 inches at 200 yards.

The MV I have for the Hornady 300 Blackout 110 grain V-MAX load from a 9" barrel is 2180 fps. The factory G7 BC of the bullet is 0.135, and according to the AB solver, the wind deflection would be virtually the same at 200 yards, about 17.6".

A subsonic 300 BLK load is the Hornady 190 grain Sub-X with a G1 BC of 0.437. The 9" MV I have is 1041 fps, and at 200 yards the wind deflection would be about 5.12 inches.

All that is of course based on ballistic calculations, not my own experience.

I have some different flight numbers -- based on my actual muzzle velocities and JBM calculations. Inputs are 9" barrel for the 9mm, 11.3" barrel for the 300blk, 2" sight height, 7500' DA, 50 yard zero, data at 200 yards, 10mph crosswind.

9mm SBR, 115 FMJ S&B, 1347 fps MV, BC of .139 G1 (note that Blazer 115 has MV of 1295)
- drop of 16.1 MOA -- 33.7 inches
- drift of 7.9 MOA -- 16.4 inches

9mm SBR, 147 FMJ Blazer, 1298 fps MV, BC of .183 G1 (using Winchester 145 grain FMJ data)
- drop of 16.0 MOA -- 33.4 inches
- drift of 6.0 MOA -- 12.6 inches

300blk SBR, Hornady 110 Vmax, 2347 fps MV, BC of .290 G1
- drop of 2.4 MOA -- 5.1 inches
- drift of 2.3 MOA -- 4.8 inches

300blk SBR, Hornady 190 SubX, 1109 fps MV, BC of .437 G1
- drop of 19.0 MOA -- 39.8 inches
- drift o f 2.2 MOA -- 4.6 inches

I shoot my two short 9mm carry guns at 100 yards pretty regularly.

They both like 115gr best at normal pistols distances.

They both shoot 147gr MUCH better at 100 yards and beyond. Why or what that means... I suppose it could be a few things.

For a fun range gun, 9mm and it isn't even a contest.

The only real advantage of 300blk is terminal energy and the ability to have moderate rifle ballistics with just a swap to a magazine full of supersonic ammo.

My 9mm PCC is my favorite range toy by far. It wouldn't be the worst choice for a defensive firearm either, although I have other rifles for that.

quote:

Originally posted by cas:
I shoot my two short 9mm carry guns at 100 yards pretty regularly.

They both like 115gr best at normal pistols distances.

They both shoot 147gr MUCH better at 100 yards and beyond. Why or what that means... I suppose it could be a few things.

How high do you have to aim on a carry gun at 100?

Also to OP - It all comes down to ammo costs. If you can afford it, the .300 would be a better all around gun IMO. Otherwise, the 9mm.