a shooter here on ARFCOM contacted me about making a 300 Blackout barrel from a "take-off" 1:10 30 cal. barrel they had....

the upper is going to be dedicated to 110gr and 125gr super-sonics (not interested in subs)....

there are a couple companies now offering uppers with mid-length clamshells with a lo-pro gas block at the carbine position....these usually use a 750" A2 sight tower at the mid position and a 850" or 875" lo-profile gas block at the carbine position....

what is unique about this build is it will be built on the lines of a light weight "pencil barrel" build using a 625" A1 type tower at the mid position and a 750" low-profile block at the carbine made from the previously mentioned 1:10 take-off barrel....

Turned this......



Into this.....



Extension detail...



Muzzle detail...



Gas block journal detail...



750" handguard cap adapter down to 625"



Adapter installed....



625" tower...



A2 hider.....



Probably put it together over the next couple days....




The uppers we've done like this in the past in different cartridges have turned out great and don't expect any less with this one....and it makes good use of a barrel that was just sitting otherwise....

Will post more pics of the finished upper and range results.....

Kurt  

When I saw 300 blackout and midlength I was worried. But I see it's just a dissipator type setup and a very nice looking one at that. Good job.

Got a little more work done on Bill's upper...

Checking the barrel nut alignment with the gas tube window in the upper....



Check fitting to ensure the gas block dimples in the barrel align the gas block exactly over the gas port....



One of our new gas blocks that we had custom sized and made for us....



Check fitting the tower components before final set.....




Getting closer......


Kurt

Getting closer.....still need to hard mount the sight tower....that's about it mechanically....probably dust the whole thing with matt black poly just to color match everything and add a little corrosion resistance to the steel parts....





Next will be a trip to the range....

the A2 hider is 1/2"x28?  I have a Stevens 200 take off barrel I have been thinking of doing this exact same thing to.....thanks for posting!

advntrjnky

Yep....1/2"x28......just be sure and check that it will pass a 30 cal bullet....all the A2s I've been getting for the last few years have worked fine.....then you could also use a 9mm....1/2"x36 if the Vodka serves me correctly....

Got a chance to take another project to the range today....

The "take off" barrel 300 Blackout is pretty much finished....

Ran it today with the Hornady 110 V-MAX load.....they were clocking a little over 2,400fps out of the 16" 1:10...

Its twin sister will probably end up on the EE in a couple weeks....

Recently finished another 300 Blackout from a recycled 'take-off' barrel....

This one started life as a stainless Remington 700 1:10 300SAUM and was re-birthed as a carbine length 300 Blackout....



Ported to run with loads as light as 110gr using a standard weight carbine buffer and spring...tested with 110gr M1carbine, 110gr factory VMAX load, and 120gr PSP....



We did our normal indexing of barrel curve to top dead center, ported for super-sonic loads, threaded the muzzle 5/8"x24, and put a 11 degree muzzle with lapped crown...







The factory Hornady load basically shot one ragged hole at a hundred....we had near perfect shooting conditions before a front came through, and the 20X sure helps my aging eyes....but all in all it's another great shooter...

my first 300 blk/ 300 whisper was from a Remington 700 .308 take off barrel, that a machinist friend of mine, made into a 16 inch 300 whisper AR 15 barrel.  I originally was just going to focus on lightweight super sonic loads but began to play with the subsonic loads and fell in love with it.  I have shot 220gr jacketed out of it with good accuracy.  It likes my 247 Cast boolits also.  I even have it working with subs with out the can on.

Nice work and good work at recycling those barrels.

Sweet!!!

Nice Stick!!

Seems like a good bit of what I've been working on for the last several months is 'recycle' jobs....which is fine with me, usually when the old chamber is cleaned off you start with a good pre-seasoned bore....put a straight chamber and muzzle on it and they usually shoot good from the git-go.....

We've run flat-base 220 subs through a can with a 1:10....just need to be very sure of the set-up (velocity,  alignment,  velocity. ...did I mention velocity )

The boat tail 220s you can visually see doing the duck-ball wobble on a clear day with the sun at your back...

Thanks.....it's always good when a plan comes together

Nice job! Great photos too!



How much would the cost be to spin down a .308 Rem 700 take off barrel if I you were so inclined?  Give me an excuse to put a really heavy sweet barrel on my 700 Sendero!