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There is a company in Omaha, NE (AAA Ammunition, www.aaa-ammo.com ) that has a semi bore-rider bullet. It weighs 705gr and is moly coated. In my BMG rifle with a 30" barrel, I was getting 2975fps with no signs of pressure. However, with a conventional heavy Ball & AP (both weigh about 700gr) I could only get 2700fps before there were pressure signs. The reason for this higher velocity & lower pressure is the persence of a 'driveing band' on the 705gr bullet. From the point of the bullet to the first level ring it increases in diameter, but at the first ring it is .500" (the diameter of the tops of the lands of a 50 cal rifle such as a BMG, JAB, A-Square, Peacekeeper, ect). This allows the bullet to ride the tops of the lands and center itself in the barrel for greater accuracy. Then there is a .495" groove. The next ring which is called a 'driveing band' is .510 which is the diameter of most all other bullets for .50 rifles, however this ring is only about .2" wide. Then there is another .495" groove. The last driveing band is about .3" wide and then it tapers into the boattail. The increased speed and lower pressure are attributed to these driveing bands being the only surface to actually 'dig in' to the bullet. Also, since the bullet is moly coated the coefficent of friction is less than an uncoated bullet. The accuracy is furthered by the presence of the .500" diameter centering itself in the bore. These projectiles are widely used in .50 BMG 1000yd competetions and are extremely accurate. I was out on Mon PM with my .50 BMG and shot 3 shots at the 1000yd NRA Highpower targets. Fortunately there was no wind so the inherant accuracy of the bullet/powder/brass/primer combo could shine through. My 3 shot group was 5" at 1000yds. This is a PIC of the actual round I will use in competetion (not the Ball or AP). It is seated .015" off the grooves in my BMG that has a standard chamber, ie. NO SPECIAL CHAMBER REQUIRED. They are $1.60 ea which is cheaper than a Barnes, Woodleigh, ect. Try 25 or so for increased speed & accuracy and lower pressure & recoil.
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Moderator |
They sure look cool! Now if they could just make a 750 gr with a large blunt nose, say .40" dia meplat, then we would have the be all, end all solid in 50 caliber, heck, I'd be happy with a 600 gr truncated cone solid. Speaking of 50 caliber bullets, I haven't looked lately, but is there a 600 gr rn soft out there? I'm real tempted by the 570 gr XLC, but something about the Jeffrey just screems, rn soft. | |||
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One of Us |
Paul, Check the Hawk site. THey have 600 grain round nose softs for $44.50/box of 50. I used Hawk on elk with very impressive results. THe accuracy is not quite as good as Woodleigh, but not bad. | |||
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Moderator |
500, Thanks, I've heard some mixed and negative comments about Hawk bullets, but can't argue with the price. For what I'd be using it for, target accuracy isn't needed. I do have 200 600 gr cast bullets, and will be picking up a mold, but can't quite decide on what weight or style. The NEI 680 gr looks tempting, but they have a nice 580 gr as well. I already have a 450 gr LBT that will see lots of use. | |||
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