Approximating 5.7x28 ballistics with 223 load for use in a PDW/8" AR

[newtriumph]

Hello this is my first post so please be gentle! (I have tried to research as much as I can but if this information is available with a better searching I apologize)

1. I really like 5.7x28 as a rifle cartridge (conceptually) for use in home defense

2. I can't sbr nor use a suppressor where I live, but I can use an ar pistol (which I do already own)

3. I'd like to avoid unwieldy options (like a hokey 30" california PS90 or a 16" ar-57 upper) which is what would be required to get something capable of shooting 5.7x28

4. I don't want the fiveseven pistol because the 5.7 ballistics seem poor with a pistol and i also am not a good shot with a pistol (which of course might be the easiest thing to remedy!)

My priorities for an ideal cartridge load are

1. terminal effectiveness
2. low flash
3. low overpenetration

lower priority but important to me...

4. lower destructive hearing damage potential (like 160db vs 168db is all i'd hope to achieve)


I'm not concerned with barrier penetration nor "heavy duty" threats as I have other rifles.

Varmint rounds seem to already be close to what i'm looking for, but there is a lot of powder in those loads, I believe, and they are designed for longer barrels

So i'm wondering if there's a way to load a 35 grain or 40 grain bullet in a 223 that would approximate the things I like about 5.7x28?

PS I did buy some 50 grain Black Hills TSX that is supposed to be lower flash.

thanks!

[yoni]

We tested the P90 in Israel and even though most of us thought the weapon was cool. The round flat sucked when it came to stopping people. I would rather carry a closed bolt mini or micro Uzi using 9mm ball than the 5.7 round to defend my life with.

[Leaveammoforme]

Full house 5.56 loads meet #1 and #3 of your priorities. #2 will be tough to meet with an 8 inch barrel. Although, #2 and #4 can be somewhat addressed with a linear compensator or blast shield style muzzle device.

Don't dumb down your defensive ammo.

[newtriumph]

Thanks for the replies

1. I did buy an mpx 9mm pistol to try and accomplish this goal - but as leaveammoforme alludes to, it isn't going to be as effective against over-penetration (over-penetration is probably more important to minimize than flash and noise as I think about?)

2. Sounds like some sort of muzzle device may be the best compromise and then just sticking with my 50 gr BH 556. I just need to see how that would work on my LWRC (which i know is not the most popular brand on here!)

(By the way - I hadn't come across the DocGKR 5.7 stuff - maybe I should have asked to approximate the ballistics of the KAC PDW 6x35 round? or the 5.56x30 mars type/ 5.56 short ? It seems like there is still demand for something in that space - but maybe the physics just don't end up working in the end!)

[TaterTot]

How about a 22tcm built on a glock pattern lower?

Sent from my SAMSUNG-SGH-I337 using Tapatalk

[Clint]

Yes, the 22TCM was created to duplicate or beat 5.7x28 ballistics with an OAL the same as .45 ACP.

In the end, I'm not sure it's worth going with an alternative cartridge or a custom download for HD purposes.

An 8" AR format PDW seems like a good match for the 300 BLK, but the easy choice is to bump the barrel length up to 11.5" and just use 5.56 with a low-blast muzzle device.

[newtriumph]

Yes, the 22TCM was created to duplicate or beat 5.7x28 ballistics with an OAL the same as .45 ACP.

In the end, I'm not sure it's worth going with an alternative cartridge or a custom download for HD purposes.

An 8" AR format PDW seems like a good match for the 300 BLK, but the easy choice is to bump the barrel length up to 11.5" and just use 5.56 with a low-blast muzzle device.

Would 110 gr 300 blk 8" penetrate more residential walls than 55 gr 16" 556 do you think?

[Auto-X Fil]

1. terminal effectiveness
2. low flash
3. low overpenetration
4. lower destructive hearing damage potential (like 160db vs 168db is all i'd hope to achieve)


2) and 4) are really bad in AR pistols, and there's not really a way around it. I would suggest a Sig Brace and 11.5" barrel if you want to go that way. Varmint rounds are indeed the best for what you want - 1) will suffer, but the fragmentation is still going to be real nasty.

I suggest using lightweight 9mm rounds in the MPX. It's actually manageable as a pistol (and can also be Sig-Braced if that's OK where you live), unlike the AR, and you can get get some low-penetration rounds:

http://www.midwayusa.com/product/133875/liberty-civil-defense-ammunition-9mm-luger-p-50-grain-fragmenting-hollow-point-lead-free-box-of-20

or

http://shopcorbon.com/pistol-calibers/9mm-luger/9mm-luger-p-80gr-glaser-blue

[Auto-X Fil]

Would 110 gr 300 blk 8" penetrate more residential walls than 55 gr 16" 556 do you think?

Yes. By far.

[MegademiC]

Don't sacrifice terminal performance. Thats #1 priority. Over penetration with a good round is a non issue if you get a hit. I don't know how 300blk performs through walls. I havnt seen any testing yet. But it satisfies the other 3.

[newtriumph]

Don't sacrifice terminal performance. Thats #1 priority. Over penetration with a good round is a non issue if you get a hit. I don't know how 300blk performs through walls. I havnt seen any testing yet. But it satisfies the other 3.

110 grain 300 blk out of an 8" barrel is looking very appealing as the pistol/rifle "in betweener" that i'm looking for.

And it seems like it would be fun to dial in, to boot!

thanks all

[MegademiC]

Howdy Newtruimp,

To offer a different suggestion for HD since you are worried about overpenetration inside your home:

A 18.5" barreled 12ga shotgun with #6 to #4 high brass squirrel/turkey loads.

The squirrel/turkey loads are deadly at HD ranges inside your home and will not overpenetrate through sheetrock walls.

Plus you can have a ammo sleeve on the stock or forearm that contains buckshot and slugs if needed.

HTH

Paul

Even though this has been discussed various places, I'll post it here for you. NO!

Both loads are terrible choices as they fail to adequately penetrate enough to hit vitals or cns... not to mention followup, capacity, length, weight, etc.

If your using a shotgun load, #1 shot is what you should be looking at., according to people who study the effects of actual shootings involving shotguns.

[Ryno12]

Wow. [emoji57]

[Ryno12]

It's not even legal where I live to deer hunt with buckshot, much less birdshot. You can't even be in possession* of it while deer hunting.

Take a wild guess why.

[Ryno12]

Howdy Ryno,



Sounds like you need to move to a more gun friendly state.

Paul

Edited:

I live in rural Arkansas and around here it's hunting season.

I realize this might be an impossible task but if you can get your Mom's permission to buy a gun, find somewhere to hunt, most states have public hunting lands, and kill a few things. It just might change your POV a little.

HTH.

I was going to be civil with you up until I read your edit. At that point I realized you're a bigger ***** than I thought and therefore not worth any more of my time.

[Kain]

I don't even know where to start with this. This ain't even questions that the OP is even asking, which begins to make me wonder if we don't have Uncle Joe here trying to push his shotgun ideology.

I suppose I will go with this. People have managed to kill moose with a .22lr. Does that mean I should grab my 10/22 and head for Maine? No! Just because it is possible doesn't make it practical or cause it to make sense. One should pick the best tool for the job, unless there is no other option. I have also known guys who have laid a load of heavy bird loads into deer and did dick all to the deer other than cause it to run just that much faster, which pretty much is the point that one finds when they look at birdshot shootings, sure people have been killed with it, but plenty have had minimal injuries making it a bad choice for trying to kill someone who is intently and actively trying to kill you. I will also add that using or trying to use birdshot while hunting big game is at best unethical, and at worst criminal, especially when there are readily available purpose designed loads. Yes, in a pinch everything becomes defensive ammo and, but if you have better more proven options, and better tools for the job they should be chosen first, to do otherwise reeks of stupidity.

I would suggest that one do some reading up on why a shotgun has fallen out of favor as a defensive firearm in a majority of circles. Again, some reading will enlighten one, and one might understand that while a shotgun can be used, there are often better options out there for various reasons.

So in short, while a load may be lethal, it doesn't make it practical, a choice load, or even intelligent to use when there are other options. Also, I can speak from experience that a pheasant load isn't a load I would recommend for defensive work. I say this because I have been shot with a #5 pheasant load. Most of the load that hit bounced, what did penetrate didn't make it much past cause bleeding.

[MegademiC]

Edited sarcasm out.

Kain's response was much better than mine.

OP sorry for hikacking, I suggest you do in depth research before taking advice in this thread.

I'm out of this one.

[newtriumph]

No problem at all. None of this internet stuff ever bothers me and appreciate all the help.

i bought a kx3 to direct blast forward out of my 556 8.5" lwrc for now. With lower flash defense ammo and a weapons light anyway i hope to keep my vision. (i would have bought Clint's, but the faux suppresor appeal of the kx3 was just too much since i'm in a non-supressor state!)

300 blk also is gonna be in my future.

5.7" x 28 doesn't seem like the way to go the more i research.

thanks again!

NT