PDW Cartridges

Suputin said:
I REALLY like the 300 Whisper in an AR based PDW. Subsonics give up nothing in terms of performance with very short barrels. Yet the thing can push a 110gr bullet to roughly 2200 fps or a 150gr bullet to about 1700 fps. The nice thing about the 300 Whisper is it uses all standard AR components except for the barrel itself.
Click to expand...

I was looking at some whisper info on the interwebs and came accross 300 blackout. Any thoughts? it seems to be able to push the bullets a little faster than whisper. (nearly duplicates 762x39 when using 123 grain pills) And uses the AR bolt and mag. Has any built a gun that uses this round? Also what brass is the case formed from is it 221?
 
I was looking at some whisper info on the interwebs and came accross 300 blackout. Any thoughts? it seems to be able to push the bullets a little faster than whisper. (nearly duplicates 762x39 when using 123 grain pills) And uses the AR bolt and mag. Has any built a gun that uses this round? Also what brass is the case formed from is it 221?
Click to expand...

The Black is the exact same thing as the Whisper. Just Remington got the round SAAMI spec'd.

Suggestions that the Black is somehow different or better than the Whisper is obsfucation designed to make you think the "new" round is somehow worth spending money on rather than just going with the original design.
 
fair enough i was just goin by what the numbers they gave for velocity and the different weight of bullets. It seemed hotter.
 
+1.

5.7x28, while it may be underpowered when using AP ammo, has no such issues with the civy Polymer tipped HP ammo.

The reduced recoil and ability to put multiple rounds on target with no muzzle climb, even in automatic, more then makes up for the lower powered cartridge.

If you need somthing for longer distances, why are you wasting time with a PDW? You should be using a full size rifle in an intermediate rifle caliber, Ie. .223 or 7.62x39, or .308 or better if longer range is desired.

The desired use must be taken into account when discussing these cartridges. They are designed for under 200 meters, and they are very effective in that range with the correct ammo.
 
There are a bunch of interesting PDW type rounds out there these days. A couple I came across while researching this project are 7.62x40 WT and 6.5 MPC. Both of which are based on a cut down .223 case.

The nice thing about working with the .223 case as a parent is that it fits AR mags and a standard bolt.
 
beltfed said:
I'd take .22 LR over 5.7x28....
Click to expand...

.22lr was my original choice for gotta run - SHTF - grab and go... But I'm a 5.7 convert since my testing of the P90 platform around 8 years ago... Strictly speaking from a PDW point of view, it's accurate, light, holds a considerable amount of ammunition (in un neutered form), and brings with it the ability to defeat armor (went through CRISAT like butter...). I also like that the pistol and carbine share the same rations....
 
kthomas said:
This seems like an odd choice, why not just go with the 7.62x39?

The swedish 6.5x25 CBJ seems like an interesting little cartrige:

http://www.gotavapen.se/gota/cbj/cbj_crtg.htm
Click to expand...

8x33 is really short. Like the overall lenth is 48mm so you could have a nice short action. The case head is ~11.95mm, so it's quite a bottle neck so it will feed easy but there isn't a whole lot of taper to it, so the magazine can be pretty straight.

It never really saw much service beyond WW2, so there must be a reason for that... but I still would use it, just because I think it is an attractive round.
 
PDW Catridges

I completely agree with rivetc78, a cartridge that matches your secondary, but I would pick the 5.7x28mm (P90 and Five-SeveN)

P90.png
,

800px-Five-seveN_USG.jpg
 
KevinB said:
Pick a cartridge that gives you your required performance.

I would NEVER recommend using a handgun round in a long gun. Want a handgun, carry one, put why in the earth would you limit your long gun to a unnecessarily anemic round?

I would never use 6.8 in a M16FOW -- just running the bolt thru ANSYS will show you the relief on the bolt rim does not allow sufficient strength -- 6.8 also offers a lot more recoil in small gun than really desired.
Keep in mind 6.8 was designed for a 12.5-16.5" bbl as a compromised cartridge that allowed use of the M16FOW architecture, key word compromise.


5.7x28 (FN) and 4.6x30 (Hk) where designed for a rather usless NATO cross hangun/PDW concept.
Basically you take a long gun, and dumb it down to be cross compatible.

Our (KAC) PDW was designed around an ammuntion that was purpose built for a PDW, a 0-300m requirement (PDW folks may have to shoot it out with AK weilding foes), and to function effectively in a short barreled weapon.
Click to expand...

+1

I'm sold on the KAC PDW 6 x 35mm cartridge, is this gun in production yet....I hope so, would love a civi version of it..

http://www.knightarmco.com/pdw.html
 
I'm sure a P90 or Five-seven would be lots of fun for shooting gophers. The 5.7x28mm cartridge is slightly faster than the old .224 Harvey Kay-Chuk with equivalent weight bullets. It could also be described as providing performance equal to a .22WMR rifle, but out of shorter barrels.

I call that awfully weak sauce for anti-personnel use.
 
tjhaile said:
I'm sure a P90 or Five-seven would be lots of fun for shooting gophers. The 5.7x28mm cartridge is slightly faster than the old .224 Harvey Kay-Chuk with equivalent weight bullets. It could also be described as providing performance equal to a .22WMR rifle, but out of shorter barrels.

I call that awfully weak sauce for anti-personnel use.
Click to expand...

I can vouch for the fact that the PS90 (non restricted of course...) is fun for shooting ground hogging critters... With respect to ballistics, it will throw a 36 grain Barnes Varmint Grenade out at around 3050fps... with 743 ft/lbs of energy - and in a FiveseveN pistol, the round flies at just over 2200fps, and 388 ft/lbs of energy... I'm ok with that considering it's higher than my .40 cal, 9mm and my .45 acp. I'm working on a few other recipes for both 40 grain ballistic tip, and a 50 grain match to Elites ProtecTOR II... Let the math begin...

2zyzv9x.jpg
 
thanks Stormtrooper, I only wish my math skills were sharp enough to argue the point as you just did...well done, and well said. funny thing, I've found some people judge the 5.7 round as soft, not sure why, maybe because the round was designed for military use, to replace the 9mm, and not as a long range round, (this by some gets defined as insufficient) but for closer range and to penetrate eastern bloc armour if necessary (how you can say that and still believe its "soft" is beyond me). to most that have not fired this round, or used the FN P90 and Five SeveN, it can appear as soft, but as you pointed out very nicely, it has much more "punch" than 9, 40, or 45acp....I'm not suggesting it be used to hunt moose by any means, but it certainly is not a "useless NATO crossgun caliber" either, which goes to show, more than one gun for more than one purpose.
food for thought.
Cheers
:cheers:
 
tjhaile said:
I call that awfully weak sauce for anti-personnel use.
Click to expand...

stormtrooper1015 said:
I can vouch for the fact that the PS90 ... will throw a 36 grain Barnes Varmint Grenade out at around 3050fps... with 743 ft/lbs of energy - and in a FiveseveN pistol, the round flies at just over 2200fps, and 388 ft/lbs of energy.
Click to expand...

That is very interesting information. That is very respectable considering the round that KAC has made is only a little bit more powerful, at 848 ft-lbs out of a 10" barrel.

I will personally stick with my PS90 at ~750 ft-lbs, as I prefer the ergonomics of the rifle. (Not that I dislike the AR platform, quite the opposite)

Not the weak hitter that some call the cartridge. Still not the 2550 ft-lbs of a 7.62x51, but the intended purpose is not the same for a PDW as a full power rifle.
 
SCDL said:
.223 cut at the shoulder with a .357 bullet seated in it would be interesting.
Click to expand...
Its been tried in .40 already will less than stellar results.

Keep in mind the PS90 has a 16.1" barrel
The P90 has a 10" bbl, and velocity is a lot different.

I've got some rather disturbing images of the results of 5.7 and 4.6 bullets failures to stop in Afghan. They are close in headshot bullets, or you need to bullethose the target, and still don't get immediate incapicitation.
 
KevinB said:
Its been tried in .40 already will less than stellar results.

Keep in mind the PS90 has a 16.1" barrel
The P90 has a 10" bbl, and velocity is a lot different.

I've got some rather disturbing images of the results of 5.7 and 4.6 bullets failures to stop in Afghan. They are close in headshot bullets, or you need to bullethose the target, and still don't get immediate incapicitation.
Click to expand...

I have heard the same thing about the 5.7 x28 and the 4.6 a bullet that would better used as a target cartridge than a PDW .I seem to remember an incident that occured in Montreal a several years back Swat team officer shots a armed suspect with a P90 .The suspect after sustaining multiple hits asks police to stop shooting him and would he would surrender . Kind of makes you think about the valiabty of this cartridge for use of protecting ones life
 
You must log in or register to reply here.
Back
Top Bottom