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View Full Version : Who makes bthp molds?



Bandit86
05-05-2013, 03:17 PM
I have a browning blr in a 450 marlin, the magazine allows for pointy .458 bullets, but nobody seems to have pointy to aerodynamic boat tail molds. Ideas? I would like one in a 240 grain .312 as well

Doc Highwall
05-05-2013, 05:35 PM
Nobody makes boat tail bullet moulds. They do make moulds with a bevel base but that is it.

Bullshop
05-05-2013, 05:40 PM
NEI made a couple BT designs.

Jeffrey
05-05-2013, 06:17 PM
Get a spire point and seat it backwards: instant boat tail wide flat nose. Joking, couldn't resist, sorry. Although I have a good number of 30 cal 147gr fmj condoms. Always wondered what kind of a varmint bullet they would make seated backwards.

MT Gianni
05-05-2013, 10:30 PM
BTHP give less stability than the flat base boolits do with the pressures used with cast. Spire points lack the bore riding contact surfaces and can slump. The wheel can be reinvented but getting j word type profiles to work with cast @ cast pressures might equal a class in futility.

Bandit86
05-06-2013, 01:41 PM
BTHP give less stability than the flat base boolits do with the pressures used with cast. Spire points lack the bore riding contact surfaces and can slump. The wheel can be reinvented but getting j word type profiles to work with cast @ cast pressures might equal a class in futility.

I saw NEI had a 675 grain .458 mould. Interesting looking

btroj
05-06-2013, 07:01 PM
If you think a HPBT is going to Improve downrange ballistics on a 450 Marlin then you need to do some reading up on ballistics.

Bandit86
05-06-2013, 09:17 PM
If you think a HPBT is going to Improve downrange ballistics on a 450 Marlin then you need to do some reading up on ballistics.

Such as?

btroj
05-06-2013, 09:27 PM
Using the ballistic calculator on Hornady.com I get the following results.
A 400 gr bullet at 2000 fps sighted dead on at 100 yards
BC of .3 makes it 9.8 inches low at 200 yards
BC of .5 makes it 8.7 inches low at 200 yards

I can bet the BC increase you can get in a BTHP configuration in .458 diameter won't be that large.

The BTHP will likely be enough longer to take up powder space in the case reducing velocity some. I will also have a BT which will make it harder to shoot at those speeds without leading. It also isn't going to work with a gas check unless you intend to make a full body GC which means you now have a jacketed bullet.

Reality kinda sucks, doesn't it? I know this stuff because I asked similar questions of myself years ago. There isn't a way to make a 45 cal rifle flat shooting. Just isn't gonna happen.

What you have is a sort range hammer. Use it as such. Inside of 200 yards it will kill anything needing killing.

Bullshop
05-06-2013, 10:26 PM
""Reality kinda sucks, doesn't it? I know this stuff because I asked similar questions of myself years ago. There isn't a way to make a 45 cal rifle flat shooting. Just isn't gonna happen. ""
Why not? They do it with a 50 so why not a 45?

btroj
05-06-2013, 10:34 PM
A 50 with cast? And a bullet still short enough to reasonably fit in a 450 Marlin case and still feed thru the action?

In a single shot I could see it, in a repeater, nope.

Reality is hard to get away from

MtGun44
05-07-2013, 01:46 PM
To get a reasonably effiecient aero shape in .45 Cal is going to take 500 and greater
weight and will not fit through any repeater action due to LOA.

You CAN make a .45 cal highly aerodynamic long range cartridge - just drive that
500+ gr aero bullet/boolit at about 3000 fps. . . . Call me when your shoulder
heals up.

Small changes in aero and still running at 1850 fps is not going to make a
flat or even very noticably flatter shooter.

Look at the pointy bullets that Hornady has with plastic tips. Get a few
of these and a few flat points and launch at the same velocity and see
where they hit at 100, 200 and 300. By about 300 it should be getting
so the drop diff is larger than the group size.

I used to think about this stuff, too. Engineering mind - going to solve
the problem - I now shoot a .22 -250 for flat, .45 - 70 is fine out to
200, then get a different cartridge, unless you are playing games -
not a condemnation - I love shooting games, but they are not the
same as hunting. You can adjust the sights for 12 ft of drop at long
range, as long as the range is fixed, like in a game - bullseye or
sillywet, for example.

Another research project: Look at what the drop difference between
a 55gr FB .224 bullet at 3600 fps is compared to a 55gr BT .224 bullet
at 3600 fps - even at 300 yds it isn't squat.

Bill

Whiterabbit
05-07-2013, 02:28 PM
I saw NEI had a 675 grain .458 mould. Interesting looking

It's awesome.

http://castboolits.gunloads.com/attachment.php?attachmentid=65955&d=1364705832

Given that people shoot the BPCR design to 1000 yards, why would you want a BTHP as opposed to a BPCR bullet?

Whiterabbit
05-07-2013, 02:33 PM
Dumb question. Scopes have adjuster knobs, even irons can be found with folding leaves or long range adjustments. Why do I care if I am chucking pumpkins or shooting a laser beam? All I care about ballistically is do I have the right design to be accurate at the distance I want to shoot. (and enough knock down if I want to do more than just put a hole in paper)

IF people shoot 1000 yard competition with BPCR bullets in a 45/70 I can not IMAGINE an application you want to seriously pursue with your marlin that could not be accomplished using the same bullets.

Maybe without the same conditions (everyone else seems to think you want a flat shooter, I won't make that assumption), but the same results. Gravity can be compensated for easy. It's everything else that is hard!

Wadestep
05-08-2013, 09:54 AM
IF people shoot 1000 yard competition with BPCR bullets in a 45/70 I can not IMAGINE an application you want to seriously pursue with your marlin that could not be accomplished using the same bullets.


I can name one - hunting. The flatter the trajectory, the less accuratly you need to know the range. Also, the faster the projectile, the less wind drift (everything else being equal). Competition/plinking is one thing, hunting another altogether.

Harter66
05-08-2013, 10:53 AM
How about a 400 gr Money boolit? Move it up to 450 and hp.

The ''trouble'' w/pointy boolits is that they slump ,when they're hard enough and launched gently enough not to slump, they pencil through or break-up too shallow. Not that a 45 leaves a small hole.

Andrew Mason
05-08-2013, 11:02 AM
go to the section on gas checks,
there is a guy in there making boat tail gas checks.

Whiterabbit
05-08-2013, 12:15 PM
I can name one - hunting. The flatter the trajectory, the less accuratly you need to know the range. Also, the faster the projectile, the less wind drift (everything else being equal). Competition/plinking is one thing, hunting another altogether.

I believe Mtgun44 already addressed this.

-------------------

IMO OP, what you need is a BPCR bullet. Lots to choose from, but I would make it a flat nose rather than a pointy. That let's you get more case space to cram more powder in there.

I truly honestly recommend the LEE 45/70 bullet that is the RNFP/GC. It's 500 grains, cheap mold, and the bullet is awesome. In my pic above, the middle bullet is a 540 grain Hoch nose pour, and if you insist on spending lots of money on a mold, I like that bullet even better. Plain base, and it shoots. Lots of lube groove space and it DOES have a meplat >0 so you can still seat/lubrisize (if you want) abuse the bullet and you don't deform noses. Doesn't slump. Expensive mold, but great bullet.

People say large meplat kills, but man, when the bullet is 540 grains and bigger than .45" I can't imagine it matters!

turbo1889
05-08-2013, 04:31 PM
Yes, the boat tailed gas check idea is about the best I have seen for putting a boat tail on a cast lead boolit and and actually having a chance of it working. Although I was by no means the first person to come up with the idea I did make a small .gif image in MSpaint to illustrate the basic idea:

http://farm7.staticflickr.com/6173/6181540460_258b259bbd.jpg (http://www.flickr.com/photos/54455625@N04/6181540460/)


No I haven't made any myself or actually tested out the idea but others have done so. Usually using a lathe to turn them from brass rod stock.


As to the possibility of making a highly aerodynamic long range load for a 45-caliber rifle. Well my woman who has had a bad case of Magnum-itis ever since she was a teenager owns, shoots, loads for, and casts for a 460-Steyr as she has mentioned several times on this forum. For her long range aerodynamic loads she uses copper solids she mail orders from a company out of South Africa and they are like 500+ grains and really long and pointy and you could just about prick your finger on their tips. For cast she has a custom mold she had made by a BPCR custom mold maker make for her that is almost 700 grains and is a short but pointy tip on top of a bore rider design with a gas checked base and she cast them from really hard alloy that has some babbit alloy that contains copper mixed into it. She also loads regular 45-cal rifle boolits designed for lesser cartridges in it at substantially reduced loads with a filler.

So yes it can be done but personally 45-70 loads at full level-3 load pressures is more then enough for my needs.

Whiterabbit
05-08-2013, 04:37 PM
Well my woman who has had a bad case of Magnum-itis ever since she was a teenager owns, shoots, loads for, and casts for a 460-Steyr as she has mentioned several times on this forum. For her long range aerodynamic loads she uses copper solids she mail orders from a company out of South Africa and they are like 500+ grains and really long and pointy and you could just about prick your finger on their tips. For cast she has a custom mold she had made by a BPCR custom mold maker make for her that is almost 700 grains and is a short but pointy tip on top of a bore rider design with a gas checked base and she cast them from really hard alloy that has some babbit alloy that contains copper mixed into it. .

Hi Turbo,

Does your wife have a sister?

turbo1889
05-08-2013, 04:52 PM
Not wife (unfortionatly) . . . long time, steady girlfriend, (like nearly a decade now). She is an only child. She is less trouble then she is worth but only because she is worth a lot (she can also be a lot of trouble).

My advise to others seeking a similar woman (apparently you) would be to be warned that all women are trouble. Some are more trouble then they are worth and some are less trouble then they are worth. The thing with the kind of woman I have is that you will have the kind of trouble with her that you would not normally expect from a woman and you can get blind-sighted by that.

You wouldn't expect a normal women to give you trouble by doing the "I've got more heads on the wall with bigger horns then he does" line in front of your buddies. This kind will and that is only the start of it. Just a heads up so you get somewhat of an idea what your getting into. You can never actually know until your actually in deep but just a warning that they are all trouble and it is a matter of whether they are worth more then the trouble or not. This kind is just a different kind of trouble that is all.

And yes, I love her like crazy, otherwise I would have been out of this years ago.

MtGun44
05-08-2013, 08:46 PM
I suggest that anybody that worries about boat tails really does
look up the real world drop difference at any kind of hunting range
(IMO 400 and in) with something like a .223 or .22-250. I think
with the big and slow, it will be even less important.

Sierra has a 55 gr SPT (1360), a flat base design. The BC above 2900 fps is .237
They also have a 55 gr SBT (1365), a boat tail design. The BC above
3000 fps is .250. That is a 5% improvement in the BC.

Bill

J..
05-09-2013, 07:30 PM
I had a Siamese Mauser in .45-70 that I used to use as a test platform for various .45-70 bullets. I had an NEI 458" 425 boattail spitzer mould and ran off a few bullets. Shot them against a plainbase RN that was also 425. Same load of powder, same gun, same everything....everything was identical except the shape of the bullet. The BT shot about 18" flatter at 200 yards than the plainbase RN.

Whiterabbit
05-09-2013, 07:32 PM
I'm left wondering if thats exactly what is ballistically predicted based on differing BC values.

btroj
05-09-2013, 08:35 PM
18 inches flatter at 200? Wasn't because of just bullet shape.
Change the bullet shape that much and it changes the dynamics of recoil. A small change in barrel time or vibration could mean that bullet hit 18 inches higher at 200. Key is, where did those bullets hit in relation to each other at 50 and 100 yards? If the BT spitter was higher at 100 then you don't have a real compairison, do you?

Shiloh
05-09-2013, 09:20 PM
Nobody makes boat tail bullet moulds. They do make moulds with a bevel base but that is it.

I've seen pics of boat tail bullets. Maybe even on thsi board. Not BB mind you, BT boolits. I have no idea who made the mold.

SHiloh

1845greyhounds
05-09-2013, 09:47 PM
Accurate Molds makes some semi-pointy 46 cal (0.458"+) molds. I also thought about getting pointy 46 cal boolets. When I started looking at it harder, I decided it wasn't worth the trouble. The trajectory gains were meager and I could compensate for them with a range finder and a ballistics table. Still, pointy bullets look cool, so here's a couple links to some relatively pointy molds. Good luck.

http://www.accuratemolds.com/catalog.php?page=10

http://www.accuratemolds.com/catalog.php?page=11

If you really want pointy 0.458 pills and are willing to shoot jacketed, consider the Barnes 300 gr semi-spritzer.

btroj
05-09-2013, 09:54 PM
Pointy bullets may be fine in a single shot but they aren't gonna do squat in a Marlin.

Doc Highwall
05-09-2013, 10:02 PM
Hollowpoint is making one now and is working on design number 4 or 5, as far as producing a good workable design is going to take a while longer.

The only true way to say how good a bullets ballistic coefficient is over another is to fire it over two chronographs at the same time with one being at the muzzle and the other one at 200 yards or farther.

By knowing the muzzle velocity and how much velocity it loses at 200 yards you will be able to compute the ballistic coefficient.

Another way to show how much flatter one bullet is over another is to zero the gun at 300 yards and shoot it at 600 yards with out making any sight adjustments. But in order for this to work both bullets would have to weigh the same and have the same powder charge.

TXGunNut
05-11-2013, 11:05 PM
I suggest that anybody that worries about boat tails really does
look up the real world drop difference at any kind of hunting range
(IMO 400 and in) with something like a .223 or .22-250. I think
with the big and slow, it will be even less important.

Sierra has a 55 gr SPT (1360), a flat base design. The BC above 2900 fps is .237
They also have a 55 gr SBT (1365), a boat tail design. The BC above
3000 fps is .250. That is a 5% improvement in the BC.

Bill

Back in my j-word days I got out a calculator and ballistic tables (remember those?) and did the math on a legal pad for 165gr BT bullets in my .30-06. Difference was negligible until I got waaay past my comfort zone for a hunting shot. I even tried a few BT's in a problem rifle awhile back hoping the difference in bearing surface would make a difference. It didn't. Go ahead and crunch the numbers, today you can probably use a computer to do it. As noted above it will be an exercise in futility.
Those BT gas checks do look kinda sexy, tho

btroj
05-12-2013, 07:54 AM
Anyone ever woder why the BR shooters use flat based bullets at 100 and 200 yards? Maybe it is because at those ranges they are more accurate.

I also have never heard of a BPCR shooter using a BT cast bullet. I am sure that if they were an advantage that crowd would be all over it.

Bandit86
11-08-2013, 10:33 PM
Sorry guys, work had left me little time to visit.

Why? Because my rifle has 3500ft/lbs of muzzle energy and barely 1000 at 300 yards, basically drops 800 ft pounds for every 100 yards. I simply wish for my bullet to retain bit of velocity velocity hence retain energy. That's all. Impossible? Maybe. But the idea of throwing a 400 grain chunk of metal to 400plus yard excited me

I would like to do a bit of slow speed (sub sonic?) cowboy shooting (Cas member) and use the slow lead bullets for intermediate distances

I shoot both the 325 grain leverevolution that drops only 21 inches at 300 yards and 350 grain jhp that drops 38 inches, the factory 325 kills the shoulder, my reloaded 350 are nice and mellow yet just as fast, is like to find what powder the factory uses

bhn22
11-09-2013, 10:35 AM
It would be a really long bullet, requiring a really fast twist barrel. Even the jacketed bullet manufacturers don't offer a .458 boat tail, and the Quigley guys use square, plain-based bullets. This suggests to me that such a bullet design is ballistically impractical. Especially in a magazine rifle. You'd get none of the benefits, and all of the headaches. You could likely have a mold custom made, but I suspect your bullet weight would need to be kept around 300 grains or so to make it fit in the magazine. Then would you be able to drive it fast enough to see any benefit?

ohland
11-29-2013, 10:31 PM
Anyone ever woder why the BR shooters use flat based bullets at 100 and 200 yards? Maybe it is because at those ranges they are more accurate.

It takes time for a boat tail (or any bullet) to go to sleep (nutating, or yaw, IIRC). So for ranges 200-300 yards, a good plain base is just as competitive as any boat tail.