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Posted: 10/7/2007 11:54:12 AM EDT
| i'm still new to this forum and my question will 50 grain bullets be too light to shoot out of a 16 inch barrel out to 400 yards or should I go heavier bullet weights ? barrel is a 1 in 9 twist |
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Generaly speaking, heavier bullets will do better out to those longer ranges. Your barrel is capable of stabalizing 69 gr. bullets, which will hold their velocity much better than a stubby little 50 grain bullet. This translates into more accuracy and punch out to those ranges. So no, they probably wont work with your 1-9 out to 400 yards... Try some 69 grain Sierra MatchKing HPBT's... they are nice....cheep too... |
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Bullet weight and barrel twist are more related thanthe length of a barrel when it comes to bullet stability. In general a faster twist rate is required to stabilize heavier bullets. -1:12 is for 40-55 (some barrels will stabilize up to 65 gr) -1:9 will work for 40 grains through 69gr. (some even do well with bullets up to 77gr) -1:8 will work on the full range from 40 gr to 77 gr. Some folks find that 50gr and lighter don't do as well in these My 1:8 seems to like them all just fine with the right ammount of powder behind them. -1:7 twist is for 55-80gr. Specifically designed to stabilize newer tracer rounds at the time of adoption. (it also works pretty well with the full weight range). Barrel length does have more to do with velocity, as the powder is allowed to expand and push the bullet down the barrel for a longer period of time. This will make the a projectile of any given weight fly farther before dropping as much. (flater trajectory). Accuracy is not affected by the length of the barrel as it is simply a function of making the bullet move as close to teh same for each shot. So a barrels consistency in its influence on the bullet is the most important function in accuracy. -The way the cartridge is held in the chamber, during ignition -The way the bullet is guided into the lands of the rifling (the throat) -The way the rifling engages the bullet for the length of the barrel (straightness, and consistant diameter) -The way that the bullet is sealed into the barrel as the gasses push it -And the way the muzzle releases the bullet evenly and consistantly at the crown are how the barrel contributes to accuracy. Use a good bullet of any weight, and consistant powder charge with consistant ignition and cartrige case dimensions, and any good barrel will launch it well. For your question. If you are using an optic, and know the drop of the bullet you should be able to hit pretty consistantly if it is a good barrel. The next big question is: What do you want to shoot at 400yds? Bullet weight selection is also based on what the target is. If it is paper or ground hogs or prarie dogs you should be fine out to 400yds. If it is coyotes, or bad guys you want something heavier because a lighter projectile slows down faster once it is flying through the air. Also, lighter bullets usually have thiner jackets and come apart more easily and will not penetrate deeply enough for thicker skinned and heavier animals. Edit to add a bit more info. |
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