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Anyone make FMJBT's into HPBT's?

I have heard that you actually might "blow"(extrude) the core out of the jacket if you have openings on both ends of the bullets. Might leave a jacket in the bore.
Read about this decades ago because of people cutting the tip off of FMJ rounds and using them to hunt. Whether its true or not I don't know, but it sounds plausable. Maybe if the core was bonded to the jacket, there might not be an issue, but don't think fmjbt are made that way
 
Dusty Stevens said:
The accuracy of a HP comes from its construction, not the fact it has a hole in the end.
Click to expand...
Or as I have read and heard, the HP's are more accurate because of the hollow point and not necessarily because of the construction. This from folks who are top notch F-class shooters. Are they wrong?
 
ebb said:
triangular bullet, from a square barrel, shoot out of a .556 chamber, with a home made hollow point. problem is you used a drill bit they make a tool for this its called a meplat trimmer. you have to use the tool to make the hollow point true enough to make it shoot better
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Meplat trimming is the process of cutting the meplat of the bullet (tip of the bullet) to uniform the ogive length and the frontal area of the meplat for more consistent Ballistic Coefficient (BC).
 
I say putting speed holes on a car don't make it faster any more than cutting off the tips of FMJs make them match.

Anyhoo type in "Why do match rifle bullets have hollow points" and see what comes up.

To an extent the tips can be damaged and a bullet be accurate as long as the base isn't. That's why match bullets are formed from the rear to the front. The points aren't perfect and they can be trimmed or pointed but for those shooting 1000 yards that's one of the things they do. At least that's what I read long ago.

Put your rounds on paper then show us the results. I got a ton of Hornady 55gr FMJs that would be great on the 200 yard line once they get speed holes...I mean hollowpointed.
 
mousegunner said:
I say putting speed holes on a car don't make it faster any more than cutting off the tips of FMJs make them match.

Anyhoo type in "Why do match rifle bullets have hollow points" and see what comes up.

To an extent the tips can be damaged and a bullet be accurate as long as the base isn't. That's why match bullets are formed from the rear to the front. The points aren't perfect and they can be trimmed or pointed but for those shooting 1000 yards that's one of the things they do. At least that's what I read long ago.

Put your rounds on paper then show us the results. I got a ton of Hornady 55gr FMJs that would be great on the 200 yard line once they get speed holes...I mean hollowpointed.
Click to expand...
Really? Actually Pontiac had a car that was called the "swiss cheese". It was made to compete. Google it.
Sheesh!! I know how the friggin' bullets are made and why they end up with a hollow point! What I'm saying is that there are some folks that believe the hollow point offers an advantage not because of the quality or manufacturing process but because that little hole at the tip does something that other bullet types don't. Nobody is sure why or what it is but "they've" seen results from testing. The "they've" guys have clout with the bullet makers and have had custom bullets made to test their theory. it worked but they're not sure why.
THAT IS ALL I'M SAYING!!! I don't have the clout or resources to get all techy tech, I just have a lathe and a bunch of bullets and I want to see if there's any merit to what I've heard, read and watched. If it don't work then I'll know for sure rather than listening, reading, watching a bunch of BS. If it does work, I think I'll just keep this secret to myself and you all can go....
 
Perhaps an aerodynamicists will weigh in on this topic… but it’s my understanding that the lead being in the rear of a hollow point places the center of gravity near to the center of pressure while in flight which is a more stable configuration. I’ve been wrong before and no doubt will again… but it’s part of the learning process!
 
rwj said:
Perhaps an aerodynamicists will weigh in on this topic… but it’s my understanding that the lead being in the rear of a hollow point places the center of gravity near to the center of pressure while in flight which is a more stable configuration. I’ve been wrong before and no doubt will again… but it’s part of the learning process!
Click to expand...
That's about right !! Drilling out a tip, transfers the most mass to
the base. The ass heavy bullet will tend to want to swap ends sooner.
You will need more velocity to stay above the transonic zone for the
range you plan to shoot. Keyholing would be the least of your problems.
With exposed lead at both ends, Pressure will not be your friend at some
point.
 
rockhound78 said:
I have heard that you actually might "blow"(extrude) the core out of the jacket if you have openings on both ends of the bullets. Might leave a jacket in the bore.
Read about this decades ago because of people cutting the tip off of FMJ rounds and using them to hunt. Whether its true or not I don't know, but it sounds plausable. Maybe if the core was bonded to the jacket, there might not be an issue, but don't think fmjbt are made that way
Click to expand...
I seen this years ago. The jacket stuck in the barrel leaving an obstruction. The next shot blew up the barrel.

Just buy yourself some hollowpoints.
 
Catbird said:
I seen this years ago. The jacket stuck in the barrel leaving an obstruction. The next shot blew up the barrel.

Just buy yourself some hollowpoints.
Click to expand...
It's not that I don't have any hollow points, I got a truck load. It's about confirming what I read/heard/saw somewhere a few years ago.
However, what you presented does indeed sound plausible. I will be sure to thoroughly inspect the barrel after each shot.
 
Fuj said:
That's about right !! Drilling out a tip, transfers the most mass to
the base. The ass heavy bullet will tend to want to swap ends sooner.
You will need more velocity to stay above the transonic zone for the
range you plan to shoot. Keyholing would be the least of your problems.
With exposed lead at both ends, Pressure will not be your friend at some
point.
Click to expand...
I do believe that what you say is plausible, hence the experiment for confirmation.
Since nobody has stated that they did what I'm proposing and posted any results, I am willing and eager to be the first, if I am indeed the first.
 
rwj said:
Perhaps an aerodynamicists will weigh in on this topic… but it’s my understanding that the lead being in the rear of a hollow point places the center of gravity near to the center of pressure while in flight which is a more stable configuration. I’ve been wrong before and no doubt will again… but it’s part of the learning process!
Click to expand...
Or perhaps an external ballistics engineer who has conducted this experiment and has published data that we all can examine.
 
Under some barrel conditions, the bullets lead core may become liquid. The open base will allow pressure to blow the core out of the copper jacket.
Leaving jacket in bore.

Or just load FMJ bullets nose first.
 
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