Backpack rifle/pistol builds.

[trident3339]

Ok, so I've been working on building pdw type guns for a while in different formats. The criteria is the weapon has to fit into a backpack no more than 20.5 inches tall and it has to be able to be fired upon coming out of the bag. So far my configurations have been: 4.5 inch 9mm 6 inch 300blk and 7.5 inch 5.56 ar15 based guns utilizing the maxim pdw brace,usually with an Over all length (oal) between 19 and 21 inches.
the sig rattler using any collapsible or foldable brace option between 16 and 19 inches oal.
The p320 in a b&t chassis, oal is the length of the chassis as well as the x01 chassis which depending on brace or stock used comes out between 17 and 20 inches oal.
Glock roni setups.

Has anyone else done anything similar? What Was your configuration? What options am I not seeing? Aside from the atrocious flux brace for the glock, and mpx copperhead.

 

[SOLGardener]

IMO, caliber and the probable application makes a difference as well as muzzle blast.

5.56 in a really short barrel loses a lot with tiny ice pick bullets and muzzle blast is huge for not a lot of energy on target.

You know what 9mm brings to the table and it doesn't change much between 4.5" and 10" barrels.

300BLK has some edge in a short barrel and muzzle blast can mirror either of the above depending on whether you shoot supers or subs.

7.62x39 mimics 300BLK in supersonic fashion, and delivers good energy but with a hammer upside the head for muzzle blast.

If urban application is likely, a rifle caliber in a subgun size will make you deaf in short order, whereas a 9mm will take a little longer.

I have a few of these and some in the works:
MP5 clone is right at 19" or 26" suppressed
AR pistol in 10" 5.56 is around 23" (haven't measured) and around 27" suppressed
Yugo M92 will be around 19-21" when Form 1 comes through.

Both the MP5 and Yugo will fit in a backpack. AR could if I went with a shorter brace (using the SBA3 now)

 

[trident3339]

Urban applications are most probable. The idea is to be able to move freely with a "rifle" and not appear as such for edc, post shtf applications, and general portability of amore capable weapon Muzzle blast is a concern but not nearly as big a concern as the effect of the round on target. The m92 oal configuration I built was WAY TOO HEAVY. the mp5 is one gun i wish I'd never sold as it filled this role well.

 

[poopdaddy]

i know its a td,but you could do a non td or just not split it. its also a very small cal.
but you can carry a butt load of ammo and they are pretty dependable..
https://www.theoutdoorstrader.com/threads/poop’s-deuce-deuce.1951619/

 

[trident3339]

i know its a td,but you could do a non td or just not split it. its also a very small cal.
but you can carry a butt load of ammo and they are pretty dependable..
https://www.theoutdoorstrader.com/threads/poop’s-deuce-deuce.1951619/

That's a nifty set up. As a small game hunting implement, or stop gap weapon it could be a useful tool.

 

[41mag]

Go with Ruger Super Blackhawk .45lc/.45acp convertible with 10-1/2” bbl
..... very accurate!!

 

[trident3339]

Go with Ruger Super Blackhawk .45lc/.45acp convertible with 10-1/2” bbl
..... very accurate!!

ive looked at going with strictly pistols, but I find it far easier to shoot a rifle on the move.

 

[SOLGardener]

Looking at some numbers for 5.56 (77gr. @ 2,500 fps) and 7.62x39 (123gr at 2050fps) the energy out to 100 yards is very similar, around 900ft lbs, but the 77gr is more dependent on the bullet coming apart since it's only about 60% of the weight.

55gr in an AR pistol is down around 750ft lbs and with a bullet that will not likely diverge from it's path. 62gr M855 is about worthless when slow. Bullet choice matters a lot with 5.56.

My AR pistol is pretty light and around 5.5 pounds. My Yugo is barely heavier, but because there is no weight behind the grip, it feels front heavy.

The AR pistol with a suppressor feels 5 pounds heavier since the added weight is at the muzzle.

The MP5 checks a lot of boxes for me. It can be quiet and it can deliver a large enough hole to leak from.

There is no right answer which is why I have a few different choices in short guns.

FWIW, my HK91 will fit under a jacket and the sling can be worn backpack style. It'll deliver a lot of energy through anything.

 

[trident3339]

SOLGardener I'd be interested in seeing the ptr 91 setup.

 

[SOLGardener]

Bottom left method, but with a collapsible stock, the receiver is at the shoulder instead of the stock. On the 91, the muzzle is in the same place, just below the belt line, but that's with a 17.7" barrel. with the MP5 it's all against your back. Love those HK slings.

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