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Post by Lee Martin on Feb 12, 2013 17:17:05 GMT -5
I haven't tried the 647 gr Barnes TSX yet. Their 800 grain banded bore rider is very accurate and is outstanding for 1,000 yard work. Hornady's A-Max is still the best BMG bullet I've shot to date though. -Lee www.singleactions.com"Building carpal tunnel one round at a time"
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Post by Lee Martin on Feb 13, 2013 16:43:09 GMT -5
Side note - Graf & Sons has US 869 and Barnes 800 gr .50 BMG bore-riders in stock. I just purchased two 8 lb jugs of the 869 and six boxes of the Barnes. That purchase didn't clear them out so if any of you need those for BMG shooting I'd hit their website fast. -Lee www.singleactions.com"Building carpal tunnel one round at a time"
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Dennis
.30 Stingray
Posts: 112
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Post by Dennis on Feb 13, 2013 18:57:30 GMT -5
Well the bullets were gone but did get 8 lbs of US869. Have 4-5 lbs now but that doesn't go far at 250gr per round.......
Still on the hunt for bullets.
Dennis.
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Post by Lee Martin on Feb 14, 2013 14:37:01 GMT -5
The bore rider 50 cal bullets can be hit or miss. It really depends on the gun. They’re designed for chambers with bore rider throating. Shooting these in standard 50 cal barrels can be problematic. While not unsafe they tend to be erratic when it comes to accuracy. Let me explain for those not familiar with the bore rider design. Essentially the slug has two engagement bands joined by a recessed area: This shape was common to 20mm (and larger) projectiles and was commercially offered by Herters for small-bore rifles (ie, the Wasp Waist). The bore rider chamber itself contains a very short throat and rifling lead. Remember, 50-cal barrels are 0.500” on the land and 0.510” on the groove. Bullet seating involves either the front band touching the land or being within a few thousandths. As you’d expect, these short throated chambers can prevent the use of other bullets such as military ball and Hornady’s A-Maxs. The front band “rides” the rifling and is only imprinted by 0.002” or so. The rear band, which is pretty short, contacts the full groove. Obviously this imparts less resistance and bolsters velocity. In a standard, long-throated 50 the front band is largely unsupported prior to hitting the rifling. That isn’t a problem with traditional spire points but the bore-rider has a very short bearing surface. In fact, the driving band is only 0.20”. The debate over solids versus lead core 50’s will continue. The same goes for conventional versus bore riders. Most 1,000 yard records are shot with bore-rider solids however. At last check the 1,000 yard aggregate record was with an 808 gr Lehigh. My State Arms .50 BMG shoots best with A-MAXs but is accurate with the 800 gr Barnes bore-rider. I ordered a hybrid chamber though (intermediary length throating and a fairly tight chamber; but not as tight as match grade). In the end, premium 50 caliber bullets don't net you much until you move beyond 300 yards. I've shot some outstanding 200 yard groups with Winchester 647's and even pulled and resized military surplus. -Lee www.singleactions.com"Building carpal tunnel one round at a time"
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Post by Lee Martin on Feb 14, 2013 15:55:46 GMT -5
Have 4-5 lbs now but that doesn't go far at 250gr per round....... Dennis...one word of warning on Hodgdon's data. Their peak charges for H50BMG and US 869 can be too much in some guns. I'm not sure what they used as a test barrel but in match-grade bolt actions they can be awful stiff. They may have tested with an old M2 blank and those were known for have very long and very large throating. In tight chambered, short throated barrels some guys are seeing excessive pressure with the following loads: 250 grains of US 869 (A-Max & 800 grain Barnes) 233 grains of H50BMG with the A-Max I never go above 225 grs of H50BMG with the A-Max and that's really hot. I've held my 800 gr Barnes bore-riders to 215 grains of the same. Hard to beat these bullets though on flight. The Barnes 800 has a BC of 1.05. -Lee www.singleactions.com"Building carpal tunnel one round at a time"
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Dennis
.30 Stingray
Posts: 112
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Post by Dennis on Feb 14, 2013 16:59:39 GMT -5
Very good information Lee. Thanks.
Dennis.
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Post by Lee Martin on Feb 15, 2013 9:05:11 GMT -5
Dennis....I should add that Lehigh makes an outstanding hybrid bore-rider. It's a 800 grain solid brass bullet that sports a 0.504 etching band: The calculated BC is 1.124 and they go for $2 a pop. I've yet to shoot these but hear they perform extremely well in standard chamber 50 BMGs. -Lee www.singleactions.com"Building carpal tunnel one round at a time"
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