Thinking about a 5 inch 300 BO with a folding brace.

KnotRight

KnotRight

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I got a wild hair up my a$$ to build a very short barrel 300 BO that will fit into a single sling back pack. I have a lower built out, just need the folder. I might have an upper somewhere ready to be built out. I know that I need a handguard, barrel and a comp to put on the end.also a gas block ( that I have in the parts bin). I am assuming I would need a pistol length tube. I do not want to SBR because I will be carrying it between states. And to save space, time and money, no suppressor. Thinking the additional parts should run around 300 dollars it I have to buy them new. Open to suggestiond!!!!@
 
KnotRight said:
I got a wild hair up my a$$ to build a very short barrel 300 BO that will fit into a single sling back pack. I have a lower built out, just need the folder. I might have an upper somewhere ready to be built out. I know that I need a handguard, barrel and a comp to put on the end.also a gas block ( that I have in the parts bin). I am assuming I would need a pistol length tube. I do not want to SBR because I will be carrying it between states. And to save space, time and money, no suppressor. Thinking the additional parts should run around 300 dollars it I have to buy them new. Open to suggestiond!!!!@
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Keeping it a pistol also allows for it to “legally” be stowed and ready to go in a backpack if you have a CCW. Can’t conceal a SBR AFAIK.
 
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barf said:
Keeping it a pistol also allows for it to “legally” be stowed and ready to go in a backpack if you have a CCW. Can’t conceal a SBR AFAIK.
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I do have 300 BOs, 16", 10" and 8.5 inch. 2 of the 3 have cans. One is a pistol, one is a SBR and the other is a carbine. None have a folder and if the 8.5" had a folder, it would still be about 2 inches too long. I got some 123 to 125 gr bullets already loaded. This builr might take a few months.
 
I had a 7” 1/5 twist Honey Badger upper for a little while, but ended up selling it because I liked my 8.5” Aero wanna-be better. The shorter you go the more finicky they get. My 8.5” eats anything, subs, supers, suppresses or not. The 7” wasn’t as forgiving. I wouldn’t bother with 5” myself but the 5.5” Sig Rattlers are popular for a reason.

I’m curious if 5” is still enough to make it worth going 300BLK vs something like an MP5K clone.
 
Jerzsubbie said:
I had a 7” 1/5 twist Honey Badger upper for a little while, but ended up selling it because I liked my 8.5” Aero wanna-be better. The shorter you go the more finicky they get. My 8.5” eats anything, subs, supers, suppresses or not. The 7” wasn’t as forgiving. I wouldn’t bother with 5” myself but the 5.5” Sig Rattlers are popular for a reason.

I’m curious if 5” is still enough to make it worth going 300BLK vs something like an MP5K clone.
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I’d think the 5 inch would need a tighter twist to keep it stable? Never looked at barrels that short.
 
For the muzzle blast/flash, reliability issues and drop in performance, I'd rather build a PCC/pistol or go with something a Desert Eagle in .357. I'm guessing that velocities for 125-150gr. projectiles are going to be around 1400-1500fps and 17-18gr of H110 is going to make a big blast in a 5" barrel. So, you'll want some sort of blast mitigation device.
 
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Color me surprised… 5.5” Rattlers chrono about 1700-1800fps for most supers! I found this on multiple sites so it doesn’t seem like this guys results are a fluke.

www.twobluescrews.com

Sig Rattler Chrono and Accuracy-ish Data — Two Blue Screws

Not many would consider the Sig Rattler a gun in which accuracy would be the main priority, but I decided to find out just how accurate this 5.5” barreled .300 Blackout could be. I thought it would also be a good time to run the chrono and see what type of velocities we could get from some of the mo
www.twobluescrews.com www.twobluescrews.com
 
OK so I posted folding dingus for this but deleted the post because buffer tube. Are you going with one of those buffer tube interrupter hinges or a bufferless upper?
 
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KnotRight said:
I got a wild hair up my a$$ to build a very short barrel 300 BO that will fit into a single sling back pack. I have a lower built out, just need the folder. I might have an upper somewhere ready to be built out. I know that I need a handguard, barrel and a comp to put on the end.also a gas block ( that I have in the parts bin). I am assuming I would need a pistol length tube. I do not want to SBR because I will be carrying it between states. And to save space, time and money, no suppressor. Thinking the additional parts should run around 300 dollars it I have to buy them new. Open to suggestiond!!!!@
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I've had the same wild hair for a while. BA does a 6" 300blk barrel that I think could be pretty awesome. I also have a Shield Arms folding AR lower that I don't really know what to do with...

Only thing that's held me back is that I already have a 8.3" 300blk upper on a sbr lower and I just can't justify a whole new build for that minor of a change.
 
Cole_McD said:
I've had the same wild hair for a while. BA does a 6" 300blk barrel that I think could be pretty awesome. I also have a Shield Arms folding AR lower that I don't really know what to do with...

Only thing that's held me back is that I already have a 8.3" 300blk upper on a sbr lower and I just can't justify a whole new build for that minor of a change.
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I have a 300blk with that BA barrel and a Nomad30 (no folding stock though). Love that thing. Shoots supers and subs without issue but did take a lot of trial and error to find the right buffer weight to get it to run reliably
 
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