Ian
Notorious member
I've shot a bunch of those bullets (circa 1990-2010) and didn't know that....but the advertised BC never did add up. Now I know why.
Hornady press release - Long Range Match bullet, the Hornady A tip
- Thread starter Rick
- Start date
I've shot a bunch of those bullets (circa 1990-2010) and didn't know that....but the advertised BC never did add up. Now I know why.
CZ93X62
Official forum enigma
THIS KIND OF DISCUSSION is why I come here every day! Bless your hearts, all of you.
I am TOTALLY out of my depth here, but I am keenly interested in learning. I'll admit it--this is the first time I have considered in-flight heating of a bullet in any context. The question definitely gives merit to the idea that cast bullets in BPCR at extended ranges behave far better that we have a right to respect, and behave more predictably than their red-coated counterparts running 3X their velocity. Like Ammhead likes to say when hunters tell him "You can't hunt effectively with lead bullets!--"Have you seen many bison lately?"
I am TOTALLY out of my depth here, but I am keenly interested in learning. I'll admit it--this is the first time I have considered in-flight heating of a bullet in any context. The question definitely gives merit to the idea that cast bullets in BPCR at extended ranges behave far better that we have a right to respect, and behave more predictably than their red-coated counterparts running 3X their velocity. Like Ammhead likes to say when hunters tell him "You can't hunt effectively with lead bullets!--"Have you seen many bison lately?"
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Pistolero
Well-Known Member
A was amazed at watching the guys at Alamogordo set up a rocket sled test run. They were testing
a new ablative coating for the radome of a high mach missile. Think about that. This was, IIRC, the AIM-54
being tested for the Navy. It has an active radar seeker, so needs to send and receive throught the nose,
and is running above Mach 3. So it can't be an ordinary fiberglass radome like on an aircraft.
In any case, I asked about the really crude looking supporting struts holding up the test article to
the sled chassis. Literally railroad rails cut up and welded together. Seemed ultra crude and really,
REALLY aerodynamically bad. They laughted and said, "Yeah they are crude, and definitely not
aerodynamic, but if we need more speed, just add another rocket motor, we have warehouses full
of them for nothing. And the RR rail is so thick and heavy that it will only melt a little bit at Mach 4
or even up to Mach 6 by the time the test run is over." Typical test runs are only a few seconds, since
the rail is only 10 miles long and at high mach that doesn't take long. They use old, timed out rocket
motors from military inventory. After a solid fuel rocket motor has reached a certain age, it cannot
be trusted, but will likely still work, so they get them and use a bunch to power their sleds.
Aerodynamic heating was something I was generally familiar with, but that two weeks spent there was
a real eye opener. Cool stuff. And they had all these cockpits of varous jets on sleds just sitting out
there baking, so I played jet pilot in some of them, of course. They had all sorts of cool stories. It
turns out that testing ejection seats ( major portion of what they do) is a REALLY good idea. They do
not always work the way intended the first few times. The said the first 4 seat B-52 test was the absolute
definition of a cluster eff----. All four chutes tangled, and four seats smashing into the fuselage and
splattering across the desert at 400 mph. It got better after that, until it actually works wonderfully now.
Bill
a new ablative coating for the radome of a high mach missile. Think about that. This was, IIRC, the AIM-54
being tested for the Navy. It has an active radar seeker, so needs to send and receive throught the nose,
and is running above Mach 3. So it can't be an ordinary fiberglass radome like on an aircraft.
In any case, I asked about the really crude looking supporting struts holding up the test article to
the sled chassis. Literally railroad rails cut up and welded together. Seemed ultra crude and really,
REALLY aerodynamically bad. They laughted and said, "Yeah they are crude, and definitely not
aerodynamic, but if we need more speed, just add another rocket motor, we have warehouses full
of them for nothing. And the RR rail is so thick and heavy that it will only melt a little bit at Mach 4
or even up to Mach 6 by the time the test run is over." Typical test runs are only a few seconds, since
the rail is only 10 miles long and at high mach that doesn't take long. They use old, timed out rocket
motors from military inventory. After a solid fuel rocket motor has reached a certain age, it cannot
be trusted, but will likely still work, so they get them and use a bunch to power their sleds.
Aerodynamic heating was something I was generally familiar with, but that two weeks spent there was
a real eye opener. Cool stuff. And they had all these cockpits of varous jets on sleds just sitting out
there baking, so I played jet pilot in some of them, of course. They had all sorts of cool stories. It
turns out that testing ejection seats ( major portion of what they do) is a REALLY good idea. They do
not always work the way intended the first few times. The said the first 4 seat B-52 test was the absolute
definition of a cluster eff----. All four chutes tangled, and four seats smashing into the fuselage and
splattering across the desert at 400 mph. It got better after that, until it actually works wonderfully now.
Bill
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fiver
Well-Known Member
I have told people that jacketed bullets will punch up and fill an over size bore.... depending.
but I have shot enough undersize jacketed bullets with good accuracy at full speed to know they are filling out the groove diameter.
it's also why I don't get all worked up about a huge starting diameter for cast bullets.
it's easy enough to manipulate the pressure timing, and [I think] it's a better alternative to pushing extra lead around or creating a trailing edge issue.
but I have shot enough undersize jacketed bullets with good accuracy at full speed to know they are filling out the groove diameter.
it's also why I don't get all worked up about a huge starting diameter for cast bullets.
it's easy enough to manipulate the pressure timing, and [I think] it's a better alternative to pushing extra lead around or creating a trailing edge issue.
358156 hp
At large, whereabouts unknown.
I've read where .308 Nosler Partitions are sometimes used in .311 bore rifles like the .303 Brit. as a dangerous game bullet. It has been demonstrated that the shank portion behind the partition can "slug up" a bit to fill oversized bore diameters. Since only high end commercial .303s seem to have .311 bores, this suggests that jacketed bullets are capable of slugging up quite a bit, .314 to .316 seem really common in military rifles.