Bubonic Upper

[AKA-Spook]

Had a ridiculously fast twist piece of 338 barrel laying around, a few other junk parts and a free afternoon.



Grendle case necked up to 338, 7.62 x 39 bolt , carbon fiber tube and some aluminum tubing....spare barrel nut, oh and a junk JP gas block that split from the other direction. So I cut it in half and used the other end.



Cant decide which side to slot the upper on and I'll likely have to do a little gas port tuning. Probably cut the barrel back too.
cases loaded @ magazine length with 250 hornady and 300 SMK , 25 G shown for comparrison.
it'll probably use somewhere in the vicinity of 8.5 grs of Enforcer to get it to 1060 fps so it'll be pretty quiet....and diameter wise, work well with a 9mm can.
.375 version coming up next.
For some reason I want to paint it industrial gloss grey ?

[Great-Kazoo]

Had a ridiculously fast twist piece of 338 barrel laying around, a few other junk parts and a free afternoon.



Grendle case necked up to 338, 7.62 x 39 bolt , carbon fiber tube and some aluminum tubing....spare barrel nut, oh and a junk JP gas block that split from the other direction. So I cut it in half and used the other end.



Cant decide which side to slot the upper on and I'll likely have to do a little gas port tuning. Probably cut the barrel back too.
cases loaded @ magazine length with 250 hornady and 300 SMK , 25 G shown for comparrison.
it'll probably use somewhere in the vicinity of 8.5 grs of Enforcer to get it to 1060 fps so it'll be pretty quiet....and diameter wise, work well with a 9mm can.
.375 version coming up next.
For some reason I want to paint it industrial gloss grey ?

Some yellow pinstripes to accent the warehouse flooring finish.

Awaiting videos of it in action.

[Hoser]

Awaiting videos of it in action.

I agree. Cant wait to see it al finished up.

[spqrzilla]

It needs flames.

[CS1983]

Is that some known caliber combo or something you came up with? Looks interesting, either way!

[AKA-Spook]

Is that some known caliber combo or something you came up with? Looks interesting, either way!

I came up with it. Looking for something like the Soviet 9x39 cartridge that would feed through an AR and have a wide selection of projectiles.
Dave at CH4D made the dies.

Im a little OCD with the Grendle case, so far Ive got reamers for .204,224,243,.257,6.5Grendle,284,308,338 and .375 X Grendle.
They are all really functional on the AR platform....as well as being pretty accurate in both AR's and bolt guns.
Getting free brass from 7.62 x 39 range pickup doesnt hurt my feelings either.

Now Kazoo has me thinking about those colored sprinkles for garage floors under a gloss clear coat? wonder how well they'ed stick on wet Krylon?

[dzeke]

Fascinating! It always blows my mind what people that are quite a bit more knowledgeable than I am come up with. Would love to see it shoot!