bullet weight and precision shooting

Goose25

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besides what a particular rifle might prefer...

what bullet weight is best suited for target shooting with an '06?

150's = faster, flatter, less recoil, ect...
180's = less wind shift, more recoil, less velocity, longer (more stability??), ect..
ect
 
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I might have not been clear what info I was seeking....

For the .30-06 cartridge what is the ideal bullet weight for precision shooting at 100, 200, 600, ect...yards and WHY? The "why" is what I'm concerned with... In the future I will be exploring into greater detail the advantages/disadvatages of the different types of bullet construction, calibre's, cartridges, ect....


an example;

150's are shorter and lighter, therefor they would need a slightly longer distance of travel to stabalize (I think) but on the other hand they are lighter and gain speed faster when compaired to a heavier bullet right? at shorter ranges (100yards) would they have an advantage/disadvatage over it's heavier brothers? ect...

other example:

180's are slower and heavier, they lose speed quicker and drop faster. but wouldn't a heavier bullet be more resilient to wind at longer ranges even though they are traveling at a slower speed? ect...




I'm just trying to figure stuff out.... maybe I'm over thinking this a little:D
 
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A bullet's ballistic coefficient is a useful guide to tell which bullet overcomes the effects of gravity, wind, and friction in the air the best. A 200 gr .30 caliber round nosed, flat base bullet has a low to medium BC., but if we take that 200 gr bullet, and make it as long as possible, so that the surface which bears upon the bore of the rifle is a short as possible, we have designed a bullet with a very high BC. If two bullets of the same weight but different BC's are fired simultaneously, at the same muzzle velocity, the bullet with the higher BC gets to the target first. It gets to the target first because it is less effected by friction in the air, so looses velocity at a lower rate. Because it gets to the target quicker, there is less time for the wind or gravity to act on it.

This get a little complicated when you have bullets of vastly different weights available, as is the case with the .30-06. Thirty caliber bullets can be lighter than 100 grs, and be heavier than 240 grs. A lighter bullet, with a slightly lower BC might give better results at long range because it starts with a higher muzzle velocity. In target shooting, a lighter bullet can be a benefit because it might generate less recoil. The heavier bullet has the advantage of a smaller powder column providing the push to the bullet, so the variences in velocity from shot to shot might be a little smaller, producing less vertical spread at long range.

In long range shooting, another issue is that bullets often become unstable when they drop below the speed of sound. It is to the marksman's advantage to try to choose a bullet which remains supersonic out to and beyond the range at which he is shooting. Some shooters believe their best bet is a medium weight bullet like the Sierra 155 gr Palma bullet. Others like the idea of a big heavy bullet which lumbers along, but gives up it's velocity more grudgingly. There is no right answer, just personal preference, once a quality bullet and an accurate load are chosen.
 
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Goose25

I think you answered your own question, your thinking to much. You didn't state what kind of target shooting so I'll ramble a bit here. When I started shooting metalic silhoutte I asked around at the club what weight bullets guys were ahooting in .308. Answer was 168gr at the chickens to turkeys and 190gr on the rams. I bought some sierra 168gr(match king) and worked up a load . Did the same on hornady 190s and good to go.

One thing I will say speed and accuracy usually don't go together----cowboy
 
"...ideal bullet weight for precision shooting..." 168 grain match bullets out to about 600. 175 match bullets past 600.
150 and 180 grain bullets tend to be hunting bullets. Accurate, if loaded properly, but not as accurate as a match grade bullet.
 
you may have to try different weights to find what your rifle likes.

I have a 308 Win70HB that won't shoot a decent group with light bullets, even 180grn were more of a pattern then a group :(

I'm using 200grn now and IF I do everything right I can normally get 3 of 5 touching at 100.

147 grn was about 6-8" :eek:

and if I recall I think the twist is someting like 1:11.5
 
Boomer's summary of exterior ballistic considerations was well stated. Another consideration is jacket to core concentricity, as excentricity here will result in wobble even with proper spin rate. Match grade bullets are supposed to have a tighter concentricity spec. compared to regular grade.

On the interior ballistic side of the equation, bullet mass and its response to the particular pressure time curve of the load will determine the barrels vibration characteristics upon firing. This will determine where and what the muzzle is doing at the most important instant when the bullet is exiting the muzzle. For precision shooting (ie. small groups) this muzzle exit event MUST be consistently reproduced from shot to shot. Sweet loads for any particular barrel are probably loads that are resulting in a vibrational node at or near the muzzle during bullet exit. This is why diddling with all the load parmeters for aparticular barrel can pay big accuracy dividends.
 
Here's a bit of history: the original match/sniper load for the .30-06 featured a 172- or 173-grain boattail. It was most famously loaded by Lake City Arsenal, and this load was used for most of the famous military sniper shooting with the '06, including Carlos Hathcock's legendary 800-yard shot of the Viet Cong general.

The modern equivalent of this bullet (even better, actually) is the Sierra 175-grain Matchking. The Sierra bullet is used (surprise, surprise) on U.S. long-range sniper ammunition in the .308. It has already been used successfully at ranges over 1,000 yards in Iraq.

Therefore, your first and obvious choice for precision shooting in the .30-06 would be the Sierra 175. A ton of other bullets will work, also, but the Sierra would be my first choice. The Hornady 178-grain AMAX would also be way up there, as would the Lapua 185-grain Scenar.

Actually, the Sierra, Nosler, Lapua or Hornady 155-grain match bullets would also be great. We Palma shooters use those bullets out of .308 match rifles all the way out to 1,000 yards. The advantage of these bullets is that they have less recoil than the heavier bullets, and you should have no problem zipping them out at 3,000 feet-per-second out of a decent .30-06. However, they do drift a bit more in the wind than the heavier bullets, and they don't need the fast 1-10" twist of the '06 to stabilize (though they work fine with 1-10" twist barrels).

Some people have mentioned the 168-grain Sierra or Hornady match bullet. This is the all-time classic bullet, designed for 300-metre shooting in the .308. Most experts agree that its range is limited to about 600 metres, though. As long as you stay within that range, it works fine, but its performance gets erratic by about 800. This is the reason why Sierra developed the 175. The shapes are different -- the 175 is considerably more aerodynamic.

The advantage of using the 168-grain bullet would be if you had a hunting load for the same rifle with a bullet like, say, the 168-grain Barnes Triple Shock or 165-grain Hornady Interbond. I'd expect the same powders to work for these bullets, with very similar charges.
 
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