stabilize?

[model 12 toby]

is there any truth to a bullet not stabilizing till a couple of hundred yards. my nephew and i was getting better groups at 200 yesterday than i could get at 100 today.

 

[milboltnut]

Contrary to what some say from there sources, a guy from my gun club said that his groups tighten up at 300 verses at 100.

 

[rsilvers]

It may be true if you are using an incorrect twist.

What is your bullet, barrel length, twist, altitude, and temperature?

 

[model 12 toby]

1200 ft., 30 inch, 1 and 9.5, 162 grain a-max. got descent groups at 600. 300 not too bad. 100 terrible, 200, all right

 

[model 12 toby]

78 degrees

 

[rsilvers]

Muzzle velocity?

 

[milboltnut]

what caliber?

 

[Dgd6mm]

162 Amax is .284 = 7MM

 

[model 12 toby]

7 mm rem mag.
3050 fps

 

[cliffy]

as an example, a .223 Remington with a 60 grain Spitzer bullet fired out of a 22" barrel with 1-in-12" twist will not burn all its powder within this confinement, if the powder burns slower than Alliant RL-15. A faster powder: RL-10x will burn before the bullet exist the muzzle. Bullet upset is enhanced by several factors: barrel length, twist rate, ambient temperature primarily. Bullet stabilization occurs at various distances down range, but it must occur swiftly since .5 seconds is a LONG time downrange. Varget seems the slowest powder possible to complete this burning cycle depending on the weather and barrel length. Cliffy

 

[rsilvers]

As a bullet goes downrange, the RPMs drop at a slower rate than the forward motion - so bullets do get more stable in flight. However, if they start out stable enough, then I don't see a problem. 3050 fps with that twist should be good.

I am not sure what the deal is. Perhaps for a high round count the 100 would be as accurate as other distances and just a small group is being misleading.

 

[model 12 toby]

1 in 11 twist on 9mm rem mag? ???
my sierra software actually says a little faster would be better like 1 in nine.

 

[milboltnut]

Sorry, 1:9 is stanard. Keep trying other powders, you'll bound to get a good 100 yard load but keep the the other load for the 2,3, and 600 yard load for longer range hunting.

 

[model 12 toby]

that might be it. maybe just toning it down for 100 if i ever did. im pretty bored with 100. id just as well shoot my cooper 221 and not waste all the powder to drive er only 100 yards.
i got 1 3 shot group at 600 that was bout as big as my hand. that's pretty good for me. i usally shoot prone off a bi pod with no rear bag.

 

[milboltnut]

Definately in the kill zone, bro..... 1 3 shot group at 600....

For the 7 Rem Mag, that's real good.... especially with all that recoil.... LOL

 

[mikecr]

is there any truth to a bullet not stabilizing till a couple of hundred yards.

No
Gyroscopically unstable bullets whack paper sideways within ~25yds. It only gets worse from there.. And a marginally stable bullet might shoot bad, but it does not get better downrange.
So tighter MOA at distance is not due to stability.

Nobody seems to know for sure, but I'm sure it's parallax.
The reason?
It's easier to set parallax with precision at distance. For example, at 500yds you're either focused or not. Cut & dry.. But up close, you can be comfortable with a wider focus range that 'seems' as close.

That said, I have always with ANY gun, shot tighter MOA further out.
I attribute atleast part of this to my glasses.

 

[model 12 toby]

it doesn't bother me as bad as it used to. 15 pound gun helps. i like trying to tame it. it helps that im kind of a fat ass. ;D
all those years of trying to overhead press 200+ helps too i think.