What the most effective / shortest barrel length for a 77gr bullet (using a 1/7 twist) out to 300M?
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What the most effective / shortest barrel length for a 77gr bullet (using a 1/7 twist) out to 300M?
Is 14.5" the ideal length for a 1/7 5.56 rifle using 77gr (SBR legal issues aside)?
I agree.
SBR and long range dont exactly go together...since 14.5/14.7" is the longest SBR length, I'd be incline to agree..
So the US Army made the best choice with a 14.5" barrel?
I thought I read somewhere that 16" is the best overall length, SBR issues aside.
A customer service rep from a manufacturer told me that most civilian SBR orders are for 12" instead of 14.5" because people feel that 1.5" isn't worth the tax stamp/registration.
If 'effective' for you is fragmentation max range, then 14.5" is the obvious answer.
If 'effective' for you simply means accuracy out to 300M, then there are other answers.
I think it has been answered above, but I will say that your question is apples and oranges........sort of.
you have 77gr pills, long range target and short barrels.
while any length barrel can get it there, the elusive part is "effective" at that 300 meter distance.
so the sum of your parts do not equal the total of the equation.
to get to the unqualified "effective" solution bigger is always better.
so within your parameters, as answered above 14.5 would be the best SBR length as it gives the best velocity down range.
but even better would be a 20-22 inch barrel with the same bullet.
even better would be a .50BMG at the same distance, and after that a 25mm bushmaster, and after that a 105mm sabot...see where this is going?
I thought there were diminishing returns past 18"?
I was interested in the shortest effective length for a 1/7 barrel using 77gr and a 1-4x scope out to 300M. I'd rather use a .308 any farther than that.
I'll SBR a 14.5" if it will be just as accurate and effective as a 16". Looking at the "Official SBR Picture Thread" it seems like most people that SBR go 12" and shorter.
Is it a waste to spend $200 + registration for 1.5"?
i think the OP is asking how long of a barrel is needed for effective fragmentation at 300 yards.
i don't have the data int front of me, but i'm sure someone does.
if you want as short a rifle as possible, while maintaining a 300 yard range, how long of a barrel do you want?
i'm thinking the 12.5 will probably do it.