Let's talk PDW's

[TGS]

Very cool build. What magazines do you prefer for the Colt pattern guns? I've got a Colt 6951 on the way and need to lay in a supply of magazines.

Just wanted to follow up with this question now that I've done some function testing with dummies and also live fire. Note that the gun functioned fine with all mags using both 124gr FMJ and Speer Gold Dot G2.

Metalform/Colt:

-you can load these easily with the tap method
-heavier body, feels more robust
-Because of the heavier and thicker body, it locks up more smoothly and more securely than the Duramags.

Duramags:

-substantially cheaper in price
-substantially lighter in weight
-feed lips are closer together, so you can't use the tap method to load these
-substantially shorter, even with the 20 round mags. I can't monopod the mag. With a Magpul K-grip, the gun lays almost perfectly level sitting on the mag and grip equally. This actually led to me bump-firing the gun

I get the impression the Metalform is the to-hell-and-back option. Both worked fine. I wonder whether the shorter Duramag will have less spring life than the Metalform. Monopod use of the mag is not as important on a 9mm PDW as it is on a 5.56 carbine, whereas a lighter and shorter magazine is objectively mo'better. I'm not sure which one I'd order more of. On Brownells, the 20-round Duramag is $25 compared to over $50 for the Metalform.

Just my random observations.

[oregon45]

Thanks for the info!

[JRB]

Project that I just assembled. The paint you see on the lower is leftover Aluma-Hyde; this lower used to be part of a Filipino MSSR build.

When my agency ditched the Colt 635 for the Daniel Defense Mk18, I thought we should've kept the Colts and turned them into a PDW to complement the Mk18s. This is pretty much my vision of that. This has a 4" Foxtrot Mike upper, Magpul K-grip, Hahn Precision mag well adapter, and Strike Industries PDW stabilizer with a 9mm PDW buffer setup. The SI setup seems to be well made, and has spring loaded deployment via push button. For my optic, I'd like to source an ACRO P2 on a scalar works mount. This will be SBRd so I can add a VFG.

As for a light, I'm thinking a Streamlight RM1 w/laser, using the tape switch on the VFG for efficient use. I don't want to put a WML on the side of the rail, and I've already sized up my lights with offset mounts and they're still way too bulky for this diminutive gun. I'm thinking an RM1 at the 12 O'Clock position (replacing the BUIS) would give me a low-profile WML with the laser functioning as a backup aiming device. My only thought is whether the extra bump of the laser on the RM1 mounted upside down on the rail would interfere with my sight picture through an ACRO P2 on scalarworks mount.

Thoughts?Attachment 92555Attachment 92556

That's a fantastic little build! Where did you find the Colt-style FM upper? Everything I've seen from FM was Glock style, and I've got pointless wantsies for an essentially identical little 9mm AR build.

A friend of mine got an RM1-G that we were messing around with recently. I wasn't smart enough to measure the height, but I'd guess around 1.5" tall off the rail. So you might need one of the taller mount options.

[TGS]

That's a fantastic little build! Where did you find the Colt-style FM upper? Everything I've seen from FM was Glock style, and I've got pointless wantsies for an essentially identical little 9mm AR build.

A friend of mine got an RM1-G that we were messing around with recently. I wasn't smart enough to measure the height, but I'd guess around 1.5" tall off the rail. So you might need one of the taller mount options.

Thanks for the props.

The FM-9 upper is from Brownells, the 4" variant. The FM uppers are interchangeable between single-feed Glock mags and double-feed Colt mags, so I just slapped it onto a spare lower with a Hahn Precision bottom-insert mag well adapter (non-permanent).

Thanks for the info on the RM-1, as well. I think my two options that I'm down to are either Ranger-banding/velcroing my 4Sevens Quark handheld to the 10 O'Clock position on the rail, hugging nut-to-butt with the top pic-rail......or, buying a CT CMR-301, which is like similar to a Cloud Defensive OWL but not quite as large. I talked it over with @WobblyPossum, and he thinks it might be too big.

So, do I YOLO the purchase? I moved my Aimpoint H-2 to the 9mm PDW and bought a CompM5s to be my primary optic on the Mk18 since the Aimpoint RDS is still vaporware......so, now's as good a time as any, I guess.

[JRB]

Thanks for the props.

The FM-9 upper is from Brownells, the 4" variant. The FM uppers are interchangeable between single-feed Glock mags and double-feed Colt mags, so I just slapped it onto a spare lower with a Hahn Precision bottom-insert mag well adapter (non-permanent).

Thanks for the info on the RM-1, as well. I think my two options that I'm down to are either Ranger-banding/velcroing my 4Sevens Quark handheld to the 10 O'Clock position on the rail, hugging nut-to-butt with the top pic-rail......or, buying a CT CMR-301, which is like similar to a Cloud Defensive OWL but not quite as large. I talked it over with @WobblyPossum, and he thinks it might be too big.

So, do I YOLO the purchase? I moved my Aimpoint H-2 to the 9mm PDW and bought a CompM5s to be my primary optic on the Mk18 since the Aimpoint RDS is still vaporware......so, now's as good a time as any, I guess.

Gotcha - wish they'd say as much about those uppers instead of saying they're all 'Glock style'.

The CMR-301 and other PEQ-style combos are great at keeping the height low but they tend to be wide and heavy. I think I'd personally go for a taller optic mount and get it over a RM1-G or similar vs making it fatter and heavier at the muzzle end on a small PDW style build like that.

[Cool Breeze]

Hi y'all - with the rise of active shooter stuff going on in America, I'm contemplating this idea. After 200+ pages, what did you all decide were good options? I'm looking for something no more than 20in with muzzle device etc. (ok if folding stock). I think that it is the largest backpack I can get away with without looking like a weirdo. 18 inch to 19 inch would be even better (if possible). Hopefully I don't have to read this entire thing...but probably will anyway...eventually.

[HeavyDuty]

Hi y'all - with the rise of active shooter stuff going on in America, I'm contemplating this idea. After 200+ pages, what did you all decide were good options? I'm looking for something no more than 20in with muzzle device etc. (ok if folding stock). I think that it is the largest backpack I can get away with without looking like a weirdo. 18 inch to 19 inch would be even better (if possible). Hopefully I don't have to read this entire thing...but probably will anyway...eventually.

The whole thread is definitely worth a read over time. What chambering are you thinking?

[WobblyPossum]

Hi y'all - with the rise of active shooter stuff going on in America, I'm contemplating this idea. After 200+ pages, what did you all decide were good options? I'm looking for something no more than 20in with muzzle device etc. (ok if folding stock). I think that it is the largest backpack I can get away with without looking like a weirdo. 18 inch to 19 inch would be even better (if possible). Hopefully I don't have to read this entire thing...but probably will anyway...eventually.

Definitely read this thread because it’s cool. Probably one of the most fun gear-centric threads in the history of the forum.

Now for my answer to your actual question, and it’s not the answer you are probably hoping for. If your primary concern is responding to an active shooter that starts killing people at a place you happen to be, a long gun of any kind is not a great idea. Chances are, the active shooter is some white guy with a long gun and you will also be some white guy with a long gun. Whipping out your sweet backpack gun because you think someone just started shooting up the food court is a pretty good way to get shot by other armed citizens who happen to be there, off-duty LE who happen to be there, or responding uniformed LE who happen to be arriving. People don’t generally carry rifles or PCCs in bags out and about in public. If someone starts murdering people in a public location and someone else sees you taking a rifle or PCC out of a backpack, they’re going to make the reasonable assumption that you’re also an active shooter and they’re going to put a bullet into the back of your head before you have a chance to start murdering people too. Or you manage to successfully take out the active shooter and the first uniformed officer on scene shoots you in the back the second they arrive because you’re some dude, not in uniform, holding a rifle, surrounded by dead bodies, just like the guy who stopped the active shooter who murdered the police officer in Colorado recently.

If you decide that carrying a rifle or PCC in a bag with you everywhere is a huge hassle and you decide to just keep it in your vehicle, it’s even less useful in the event of an active shooter. If you manage to run out of the mall and reach your vehicle, would you really grab your bag gun and charge back into the scene? You’d be even more likely to get shot by any other good guy with a gun.

I think the bag gun concept is as neat as everyone else here. I’ve got a shorty AR with a LAW Tactical folder and a B&T APC9. I’ve got bags they could fit into also. I just think it’s much more LARP than realistic. I don’t carry these things around with me in backpacks. It’s a huge hassle. Maybe, just maybe, if we’re talking about 2020 rioting, cities on fire, and groups of rifle-armed “protestors” stopping traffic, carrying a bigger gun in a bag might make some sense. The real use for bigger guns that fit in normal sized backpacks is so people don’t immediately start paying attention to you when you’re moving the guns from the house to the car, the car to the hotel, etc. @rob_s have a great example at some point of evacuating during a hurricane and being forced to overnight at a shady motel surrounded by suspicious characters. Having a more capable gun in an inconspicuous bag to bring into the hotel with you would be great. If you aren’t someone actively assigned to a security detail, carrying a rifle or PCC in a backpack with you at all times will most likely negatively impact your life as opposed to positively impacting it.

[GyroF-16]

I decided on a 7.5-8” barreled 300 BLK AR pistol w/ LAW folder. With a SF3P muzzle device attached, it’s 19-19.5” overall (folded), which allows use of a normal-sized, laptop-carry backpack.
I mentioned a “range” of lengths because I’ve built one with a 7.5” barrel, and another with an 8” barrel.

[Caballoflaco]

I came to the same conclusions as @WobblyPossum re:backpack guns and active shooters. Locally a couple of years ago a dude got smoked by the cops as he was running away with pistol in hand from a dude/group of dudes who had shot at him. (This wasn’t a true “active shooter” situation, but dudes who brought their beef with them to the mall).

I’m not sorry I built one, but the real utility is discreet transportation for road trips or riding a motorcycle to the range or even backpacking in some areas where I don’t mind the weight and want a long gun in camp, but would rather other trail users don’t know that I’m armed.