A 55gr or even lighter will stabilize in a 1:7 barrel, no problem. However, if that bullet is frangible or is of an expanding type (SP/HP) it may fail to penetrate properly as the overspin can casue the projectile to prematurely split appart when it hits stuff.

If you're going to spend $730, might as well save up a little more and get a quality upper.

You could get a colt 6920 upper for $550

http://www.gandrtactical.com/cgi-bin/commerce.cgi?preadd=action&key=6920MPU

And a Troy Battlerail for $230

http://troyind.com/%20/rail-systemsaccessories/rails/ar15m16-rails/free-float-rails/troy-battlerail-12-mrf-cx

That'll only be $50 more than the Stag.

Sure it's LH, but it's still a Stag.

There will be people that will give you anecdotal evidence that Stag is just as good.

But it's not.

 

Thanks for the input. Im leaning towards just picking up a complete upper instead of the hassle of buying the tools for building the upper. Leaning towards a 16" chrome 1:7 chambered in 5.56 for greater versatility with rounds and bullet weight. Id like to buy one with a dual or quad rail on the handguard... havent narrowed down a manufacturer, but im trying to sell myself on the stag left handed 2htl for $730 its a 1:9 but i think something in my arsenal should be made for us gifted individuals that shoot southpaw. Any other suggestions as far as manufacturers go with the same setup for less dough? (im sure the RH'd ones would sell for less) im not opposed to having a rh upper, but if im paying say $650 for an upper, why not shell out the rest for a true LH.

 

http://www.stagarms....products_id=221

It's actually the length of the projectile that matters. Since the bore size is fixed, the only way to gain bullet weight is to go long. Long and thin projectiles need more spin and time to stabilize than short fat ones.

 

No it's not. Vld bullets are usually quite long, but taper rapidly. Now think of a wadcutter, which is basically a cylinder. Grain per grain, the wadcutter is going to have more bearing surface and thus more friction. The way to gain weight without having to go longer is to take up as much of the bore as possible. You can also go longer. Longer bullets can have pressure issues due to reduced case volume. Fat bullets can have pressure issues due to more friction with the bore due to a larger bearing surface. A grain isn't a grain, because bullet profile matters.

 

Why does this matter with barrel length and twist? Because a bullet is like the tires on a dragster. You want it to hook up just right, but just because you spin the tires doesn't mean you don't go anyplace.

 

A bullet that isn't optimal for 1:9 because it is too heavy ( has too short a bearing surface relative to mass) skids on the rifling like a car doing a burnout. There's still friction, but not optimal, so in a 14.5 inch barrel, it might not get enough spin going to stabIize. In a 20 inch, it might.

 

 

Please look up Alfred George Greenhill and his rifling equation.

Please look up Alfred George Greenhill and his rifling equation.

 

I'm aware of it. You do realize that density of the bullet matters and is included in the equation, right? You do also realize its not an equation lik F = m * v^2, right?

 

Because according to that I can't shoot 55gr out of my 1:7, and I do. So do a lot of other people