.300blk barrel lengths

Preparedness Depot in Acworth, GA

AtlMedic

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Mar 25, 2015
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i know that .300 is great in shorter barrels, but does it gain much if any useful velocity in a longer barrel?

I ask because I would like to build an upper in that caliber for hunting down the road and since I won't beer deer hunting in a cramped hallway would, say an 18 inch barrel give me some added velocity to help with dropping a deer or hog?
 

Righter13

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I believe anything over 9inch (don't remember if it's exactly 9) is a waste. As the 300 was designed so that all of the powder burned rather quickly.
 

AtlMedic

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I believe anything over 9inch (don't remember if it's exactly 9) is a waste. As the 300 was designed so that all of the powder burned rather quickly.

Thank you. That's kinda what I didn't know. I know some calibers be fit a little from longer barrels but I don't know enough about the caliber and ballistics to know if it would help in this case.

Do you know if longer length negatively effect balisitics? I don't want to go SBR so would a 16 inch hurt it?
 

becausefu

Woodsman
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16 is fine ...they are found in abundance at 16". What gets tricky with a 16 is whether to go pistol gas or carbine gas. Midlength does not work.

If you are going to plan on shooting subsonic thru a 16" barrel without a can, get a pistol length gas system.

If you are only going to shoot supersonic thru a 16 then a carbine gas is fine.

If you are going to run a can on a 16 and run subsonic then you can go a carbine gas.

If you plan on shooting supers thru a 16 with a pistol gas, go to an adjustable gas block because it could be over gassed. But a 16 with a pistol gas and adjustable gas block will probably run anything you feed it with or without a can. You may need to adjust the gas block a little bUT it should run.
 
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Righter13

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If you're going to stick w 16inch I'd consider 7.62 or 6.8

I loved my 6.8 but got rid of it bc I can't hunt with a semi auto up here.
 

Red Dawn

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I'm thinking of the same @AtlMedic hunting with the 300BLK and running subs through a can. I guess SBR is the way to go here. I though the 16" pistol gas system was the way to go.
 

Cudruln

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Sounds like a party I'm glad I missed. LoL
Oh you don't even want to know.

On a serious note I am not even sure if it will work with my can. It has to have the threads extend pass the rail.
 

Red Dawn

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I'm all in on a pistol build till SBR paperwork goes through. What buffer and spring to use will milspec work or not.
 
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