11.5 or 10.5 AR barrel?
- Thread starter PanzerDriver
- Start date
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Rossiter93
Regular
- Location
- Nova Scotia
I run a krinkov style muzzle device on my 10.5", from what I understand the chamber in the muzzle device helps create extra back pressure to cycle the action even in SBR type rifles. I haven't put many rounds through my build yet, but I can say that it hasn't so much as hiccuped.
Whatever you want it to be
This. Length (i.e. dwell time) without discussion of gas port diameter is meaningless. A huge port with a 10' barrel may function fine. Adjusting the gas port can be accomplished with an adjustable gas block. You can also try lighter/heavier buffers and weaker/stronger buffer springs. The AR gas system is more complex than one variable.
The time between when the bullet passes the gas port and when it leaves the barrel is indeed important. Too short barrels may cause the bolt to unlock too early when the case is still completely expanded into the chamber before the pressure has had the time to lower a little bit, creating harder extraction because you are trying to extract a case still expanded and under more pressure from the chamber. Gas port size has nothing to do with it. This is why we put rubber D and O rings around the extractor springs to make the extractors work harder and to reduce the chances for the extractors to slip over the rims of the cases.
Using a 11.5" barrel instead of a 10.5" barrel with a carbine-length gas system is just enough to increase that reliability by a lot but this is all very technical and may not matter at all for what you do with your rifle.
Using a 11.5" barrel instead of a 10.5" barrel with a carbine-length gas system is just enough to increase that reliability by a lot but this is all very technical and may not matter at all for what you do with your rifle.
For most purposes it doesn't matter. It might take some tinkering of you build yourself.
For reliable lethality (wound channel) you need over 11.5"
But that is a moot point since we can't hunt with then here.
And that depends on ammo used.
For reliable lethality (wound channel) you need over 11.5"
But that is a moot point since we can't hunt with then here.
And that depends on ammo used.
crazyjackrabbit
CGN Regular
But she said size doesn't matter... 
But honestly how much of a differance would it make if the AR is built/tuned properly? I new to the whole AR world but, I doubt they would have all these different configurations if they couldnt be made reliable.
But honestly how much of a differance would it make if the AR is built/tuned properly? I new to the whole AR world but, I doubt they would have all these different configurations if they couldnt be made reliable.
But she said size doesn't matter...
But honestly how much of a differance would it make if the AR is built/tuned properly? I new to the whole AR world but, I doubt they would have all these different configurations if they couldnt be made reliable.
Like any item, reliable isn't always the goal, sales are. The 11.5 is a great improvement over the 10.5/10.3 guns. One inch accounts for around 4% of the overall length of the rifle. The reduced port pressure, the increased dwell time, reduced gas port errosion, reduced bolt carrier velocity, increased reliability and increased muzzle velocity greatly outweigh the 1 inch in extra length.
Aside from reliabilities ( gas port, dwell time etc). A 12.5 has better ballistic than 11.5 and 10.5 and then there were no increase until you get to about 14.5ish,15.7 inch. There was a chart done up in that manner over at the ar15 forum.
Now with regarding to reliabilities attributes, gas port size, dwell time, chamber size,headspacing and also buffer weight all has to do with reliabilities. Start with a really good barrel if you can afford it, LMT, DD. Guys over at ar15 forum saids that BCM,Noveske, Spike's has bigger than necessary gas port because they design their barrels to run with a H1 buffer at a minimum, one manufacture actually calls for H2 for a proper 3oclock ish ejection. Some of these manufactures will design to run it overgas because they are meant to go on a fighting gun and its better to be overgassed on a fighting gun that is in the middle of a sand pit then one that doesnt cycle with sands and mud in it. So do your research definitely and see what you are after.
Now with regarding to reliabilities attributes, gas port size, dwell time, chamber size,headspacing and also buffer weight all has to do with reliabilities. Start with a really good barrel if you can afford it, LMT, DD. Guys over at ar15 forum saids that BCM,Noveske, Spike's has bigger than necessary gas port because they design their barrels to run with a H1 buffer at a minimum, one manufacture actually calls for H2 for a proper 3oclock ish ejection. Some of these manufactures will design to run it overgas because they are meant to go on a fighting gun and its better to be overgassed on a fighting gun that is in the middle of a sand pit then one that doesnt cycle with sands and mud in it. So do your research definitely and see what you are after.
