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BALLISTIC COEFFICIENTS

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17 December 2002, 16:42
alaskadude
BALLISTIC COEFFICIENTS
DOES ANYONE HAVE ACCESS TO THE BC FOR .308 180 GR
TROPHY BONDED BEAR CLAW AND THE A FRAME(SAME DATA)
I CANT FIND THEM ANY WHERE? THANKS
17 December 2002, 17:43
Steve
From PointBlank bullet database:

; BRAND CALIBER WEIGHT TYPE B.C. S.D.
Swift .308 180 A-Frame .400 .271

Don't have the TBBC.

Sorry,

-Steve
17 December 2002, 17:53
alaskadude
thanks i just got the other one so ive got what i need appreciate it!!!!!!!!!!!
19 December 2002, 00:55
<Snout>
According to the tech. information Midway supplies on their web site the BC for the Swift 180 grain 308 A-Frame is .429, not 400.

The Bear Claw is listed as having a BC of .357
20 December 2002, 10:23
alaskadude
do you guys think there is a big difference in trajectory with the a frame at .429 and the bear claw with a some what smaller number of .357?
20 December 2002, 11:06
<bigcountry>
According to my trajectory program, if zeroed at 250yards moving at 3250fps from muzzle, makes a difference of -30.1" drop at 500 yards for the .427BC bullet and -32.8" drop at 500 yards for the .357BC bullet. Not enough difference for my hunting style of shots under 350 yards to make me need the higher BC bullet.
20 December 2002, 11:35
Fiftydriver
Alaskadude,

From the TBBC and A-Frames I have tested, I would have to say that for deer size critters, about 300 yards would be as far as I would shoot, for elk size and up, I would think about a 400 yard shot if everything was perfect.

This opinion has nothing to do with B.C. numbers or bullet performance on game. In fact these maybe to of the stoutest bullets for hunting heavy thin skinned game on the planet.

My problem with them is that I have only on one occasion witnessed a rifle shoot these bullets under an inch.

Most will hold around the 1 1/2" level though which is perfectly fine for the game they are intended for. This is simply because these are complicated bullet designs and the more complex a bullet, the harder it is to keep everything concentric and therefor accurate.

That said, these two companies do a fine job producing a hell for stout bullet with acceptable accuracy for big game hunting.

The difference in B.C. numbers will only be realized at ranges past 400 yards to any great extent. In all honestly, I would use the one that shot the best in your rifle and go with it.

Good Hunting and Shooting!!!

50
20 December 2002, 14:32
Jon A
To add to what Fiftydriver said, consider at 400 yds when launched at 3000 fps (I added a Scirocco in there for comparison):

10 MPH Wind Drift:

TBBC..........15.36"
A-Frame.....13.41
Scirocco........8.28

Retained Energy:

TBBC...........1640 ft-lbs
A-Frame......1799
Scirocco.......2310

What cartridge are you shooting and what ranges do you expect?

[ 12-20-2002, 05:33: Message edited by: Jon A ]
20 December 2002, 17:27
alaskadude
thanks for the input it really helps me.

im shooting a .300 win mag with a 180 grn bullet. i shot the scirocco in africa and it groups wonderfully and is great for lighter animals, and for the most part it did great job, but at close renage 140 yds i hit a gemsbok right on the shoulder bone, it just stood there and looked at us. we waited for it to fall over it never did and i finished it off with a neck shot. i took 11 animals and recovered 4 bullets. most of the bullets lost a lot of weight. some lost 90 grs. the gemsbok shoulder was just schrapnel not even recoverable. so i wanted a better bullet structure to hold together on bigger animals at higher velocity. the other big animals were all shot at a minimum of 225yds and longest 325. those bullets were on the opposite side (zebra,harebeest,kudu) but none were hit on the shoulder all rib shots. i live in alaska and go on combination hunts caribou, moose grizz. so good bullets are important, i dont hunt thin skinned game, unless its deer on kodiak island and then good bullets are still important because of the brown growlers
ive tried reloading barnes a lot. ive got boxes of that stuff and i cant get it to shoot at all.

i shot a black bear a number of years ago with a downhill texas heart shot, found the bullet in his throat and after weighing the 200 gr bullet it weighed 180 and dropped that critter hard. (same .300) so from that experience i liked what i saw. i shot a box of federal high energy and it grouped 1.5in, so i was hoping to shave off at least a .5 by reloading. still dont have the bullets yet. im itching to try it
20 December 2002, 18:19
Jon A
It sounds like you need a tough bullet. [Wink] Actually whatever type of bullet you choose you might be better off with 200's. In addition to the ones you mentioned, you might want to try the Northforks. People seem to get great accuracy from them and they are of a very similar construction to the TBBC's. Very tough but not that high a BC.

Since you seem worried about trajectory, etc, I'm guessing it isn't uncommon for you to have some fairly long shots. Even though nobody has tried them yet, I have high hopes that the new 200 Nosler Accubond will excell in that roll. An extremely high BC (.588), accuracy of Ballistic Tips and based on their construction I would guess they'll be quite a bit tougher than the Sciroccos (besides, they're heavier). I'll be ordering a few boxes for my 300 RUM as soon as they're available. I really hope they end up being as good as I think they will be.