Hollow Point Bullets

[Pavomesa]

I have this old notion in my head and with one great exception seems to have been the case for me...but does anyone else get the feeling that hollow point bullets shoot better than non HP bullets? Or am I just dreaming here?

Opinons wanted. Apply within.

[racepres]

I would like to say yea.. But, It may be that they are such a PITA [for me anyway] that we just will 'em to work!! You know.. "self fulfilling prophecy" stuff.. MV

[Ben]

Beagle says he has never seen a cast HP that shot less accurately than a solid of the same weight and shape. Says the balance point of the bullet is shifted to the rear. Makes sense.


Ben

[Pavomesa]

I think the center of gravity issue is a valid point and probably however any cast bullet shoots, it will shoot better with a good HP job on it. But Race makes a good point. Building HP's are such a pain for the guy who shoots a lot, that my question is almost academic. Who cares if the HP shoots a little tighter group. When you can build 4 times as many RN's that will work dang near as good...I tend to go with the RN.:-?

[beagle]

As Ben says, my shooting partner and I have modified a lot of moulds for HP cavities and each one shot better than before and that includes my favorite "non-shooters" the 357446 and the 429360. On those two, they did shoot a bit better but HPing was no cure for the built-in woes.

I'm convinced it's the shift in the center of gravity, but I'm just an ignorant hillbilly and don't know squat./beagle

[dakotashooter2]

I have a 41 mag mould that was holllowpointed (thanks buckshot) and have notice an improvement in accuracy. And sized down to 40 cal it is one of my most accurate bullets in that caliber too.

[Buckshot]

..............The British recognized this back in the 1860's during their heyday of long range (1000 - 1200 yard) muzzle loader competitions. The 58 cal slug in the .577 Snider had a HP, but the lead of the nose was spun over it to close the opening.

I think all jacketed match bullets have a HP don't they?

.................Buckshot

[shotstring]

I was thinking along those same lines Buckshot. At least most of the heavy hitters of the match bullet lines are HP, and as these are not performance HP designs - that is, they are not designed to expand reliably on impact - the HP can only be there for one thing. Accuracy.

[Bass Ackward]

I'm a believer.

[Pavomesa]

I can't think of a long range target bullet that isn't hollow point...even if they swage the point closed. Obviously the important thing is to get the CG shifted to the rear and all the point does is streamline the thing and increase the BC.

I love to shoot them but don't much like making them.

[Shuz]

I have had great success with HP boolits in several calibers. I usually cast with two HP moulds in tandem in order to increase the productivity. What this world really needs is a 4C HP mould design that is easy to utilize. I know the 4C HP is possible, I've used one made on a Lyman 429421, it was a little ackward, but it did turn out a bunch of HP's in a hurry! Wish I still had that mould!--Shuz

[1Shirt]

To me, I get improved accuracy from HP cast, and have had Buckshot do three of them for me. Am getting close to having him do another. He is a fine carftsman and is quite reasonable.

I believe the center of grav shift is the key. In all cases, and with the right load, those that I have had HP'd shot at least a reasonable percentage better than the original blt. That said, I traded Ben a nice 35 cal HP mold for some casting material and we have both been happy with that trade I think. Some of the groups that he has posted with that blt out of his beautiful 358W are most impressive.

I have quite a few less than 1", 5 shot groups with 308 and some of Beagle's 311413's over 21 gr of AA5744, lubed with LARS Red. Am now working on pushing that blt. over 2000, and with a softened nose using it on deer. While it is much slower as far as process, to me casting a good looking HP is a labor of love.
Just have to keep them running hot and consistant.
1Shirt!:coffee:

[DrJay1st]

I initially had a problem with the center of gravity being moved rearward helped the accuracy of the hollow point bullet. But, after thinking on this for all of 2 minutes, I have warmed to the idea. The longer the bullet, the harder it is to stabilize...right? making the front a hollow point reduces the mass in that area and reducing the mass should reduce the front of the bullets ability to destabilize the bullet (the front's influence on the rest of the bullet is reduced since it's mass has been reduced). Also, if one were to melt the hollow point bullet and a bullet without the hollow point and recast them as wadcutters...one would be shorter and thus easier to stabilize. The gun is seeing a shorter bullet in effect...I think...maybe...I don't know!
Jerry

[felix]

Jerry, that is a yes and no. Yes, because the boolit is shorter; no, because the center of pressure (a center of gravity for wind pressure) becomes shorter, but in the opposite direction and that is towards the nose. The more separation between the two centers, the more imbalance. Wadcutters, for example, seldom make it past 50 yards unless there is some kind of tit or hat to move the center of pressure back towards the center of gravity. Now, if we are shooting in outer space, there would be no need for any kind of ballistic coefficient, another measure of center of pressure (if you will). ... felix

[Pavomesa]

Within limits, I don't think the "length" of a bullet has very much to do with it's stabalization. This is much more a function of twist. The heavier the bullet, the faster you have to spin it to stabalize the thing. Of course this is keyed to the bore diameter as well.

Anyway, we can think this issue to death. The fact remains...it works.

[DrJay1st]

Sometimes I just have to accept things, but if given the choice I would rather understand.
Felix, are you saying that reducing the mass of the front makes the front easier to move off rotational axis or destabilize by the air?
Jerry

[felix]

No, Jerry, it is the shape of the front. The more square it is, the harder it is to stabilize. Keep in mind at 50 feet you would see zero difference for most instances on how the nose is shaped. You need a good nose shape to reach out and touch something. Yes, the twist has to be commensurate to assure stabilization of the whole boolit including the nose shape.

Pavomesa, no, the heavier the boolit, the less twist is needed. The external culprit is the length and shape, and internally the hardness of the boolit to grip the lands. More grip, the less twist is needed. Function of land height and lube retention around the lands within the barrel.

... felix

[fireflyfather]

With BTHP designs in commercial match ammo, my understanding is that those rounds are swagged, and the accuracy comes from having a pristine base (they are swagged from the nose, rather than the base). The HP cavity on those rounds is a leftover of that process, and the tiny remaining cavity would do little to change bullet balance or expansion.

[DrJay1st]

Hmmmm, I can see that but why the trend to these big fat fronts with the huge meplat? Is there a tutorial about the different forces at work on bullets. I would like to understand the cause and effect going on. It sure would help to eliminate some trial and error when making reloading choices.

Jerry

[Scrounger]

The big meplats are aimed at bullet effectiveness on animals. Not an important factor when shooting steel or paper, although it can be a factor, pro or con, in accuracy.

[Wayne Smith]

The big fat front with the huge meplat is a different thing. That has to do with the amount of damage the bullet does when it hits. The only role it has in target boolits is the shape of the edges of the hole it leaves, i.e. wadcutter. It has no role in long range target shooting.

[felix]

Most folks on this board are short range deer hunters. Meplat counts at all times, momentum counts when the animal coverts into a moose, or when the range increases. Most folks on this board have fast twist guns and prefer to shoot boolits slower.

Now enter my camp. I like 2400 fps as my optimum because of trajectory, and I don't like recoil, and I am not a hunter by any stretch of any thoughts, unless you consider charging beer cans a game subject.

... felix

[Scrounger]

Technically, Stabilization is a function of Rotation which is a function Twist, which is mandated by (is a function of) Length of the object in question. Everything is related.

[DrJay1st]

I'm beginning to wonder if I have enough life left to embark upon this cast bullet thing!

[looseprojectile]

Dr Jay;
I know I don't have enough life left. I started this boolit casting thing sometime in 1954. Used hollow points almost exclusively in revolters. Then came rifles, not so many hollow points. Now I am involved with exposing several new shooters to
cast projectiles. They are less expensive,ya right.
With the prices of full length gas checked bullits evolving to fifty cents to a dollar each it had to happen.
One good thing to come out of all this is I have recently been receiving large donations of lead from these new guys.
Been experimenting with using the RCBS bullet puller collets to jig up cast boolits to hollow point in the lathe with a center drill.
Life is good!