# BC's for SMKs??

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by cdmorten, Dec 4, 2004.

1. ### cdmortenWell-Known Member

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Oct 13, 2003
BC\'s for SMKs??

I'm still in the learning phase of this long range gig. I'd like to know where to find the ballistic coefficient of both a 168 SMK and a 190 SMK.

Also, any thoughts on where to find some good ballistics calculators?

Thanks.

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Feb 27, 2004

3. ### GuestGuest

Re: BC\'s for SMKs??

Try the link below, it's a real good ballistics calculator.
Wayne

JBM

[ 12-04-2004: Message edited by: Wayne McD ]

4. ### Rob01Active Member

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Re: BC\'s for SMKs??

And here's a very good ballistics program JBM

5. ### cdmortenWell-Known Member

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Oct 13, 2003
Re: BC\'s for SMKs??

On that caculator it asks for sight height. How do you measure that. It doesn't give a clear direction on the site. It's from the centerline of the barrel, but to what, bottom of the scope, middle of the scope or what. Thanks for the help.

Corb

6. ### milanukWell-Known Member

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Jan 21, 2002
Re: BC\'s for SMKs??

mid line of the sight path, in the case of a scope, the middle of the scope tube.

Lessee if I remember this right...

a) Take a pair of calipers, measure the diameter of your receiver, write that down, divide by two.

b) Take pair of calipers, measure the diameter of the scope tube (just to be sure), write that down, divide by two.

c) Take pair of calipers, measure from bottom of receiver to top of scope tube, write that down.

d) sight height should equal results from c) minus the results from b) minus the results from a), or d=c-b-a, where d= sight height.

Think thats right. I'm someone else will jump in and correct me if I'm wrong

Oh, and Sierra makes a pretty serviceable ballistics program: Infinity 5.0 (current version). RSI sells Shooting Lab at www.shootingsoftware.com, which is somewhat more advanced than Infinity, but is a little more involved to use as well.

Monte

[ 12-04-2004: Message edited by: milanuk ]

7. ### brian bWell-Known Member

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Aug 15, 2004
Re: BC\'s for SMKs??

Corbett,
You still have to be a little careful with published B.C.'s they seem to vary from manufacturer to manufacturer. Sierra seems to rate them a little more conservatively than Berger and some others.
B