Match Grade Bullets - Why Hollow Points?

[bigredhemi]

I intend to start loading for accuracy and I have been reading as much as I can on the subject. I have not had much range time as yet to experiment and try different things out. I'm not at the point, skill wise, to sweat out the .000001" of things but I do want to produce a reasonably accurate, consistant, round so I'll know if it's me and not the load.

One of the things I've noticed is that the majority of match grade bullets are hollow points - why?

It seems that having a hollow cavity at the tip of the bullet would cause turbulence. And if the opening were even a tiny bit off, considering the high velocities, would have a negative effect on the trajectory.

I do know the hollow cavity improves the sectional density but the tip of the bullet is a leverage point and can easily be thrown off course if it's not perfect. What am I missing?

I did have some time to experiment with some Hornady A-Max before all this global warming hit. I did pretty well with it out to 200 yards. Do you think the lightweight plastic point, while improving the SD, would also remedy any shortcomings the hollow point may have - or not?

Thanks guys...

[1SOW]

What are you shooting? Rifle or handgun? Caliber?

[bigredhemi]

Rifle - .222 - 30-06 - .243

Pistol - I do a lot of Bullseye shooting, .22 - and most match ammo is RN - no HP...

[deepcore]

Are you confusing hollow points with open tip points like the Match Kings.

[bigredhemi]

Well - I was considering the Sierras because of all the competitions they have won and it's hard to argue with results. Even though Sierra labels the MatchKing as a HPBT - I can see that they are not the traditional hunting hollow points.

I'm just trying to understand why a hollow topped cavity would be more accurate than a point.

AND - does the filling of the cavity, like the A-Max, maintain center of gravity, sectional density, and rotation, as well as the HP without the turbulance the hollow cavity might produce - or might not produce - I don't know?

[Ideal Tool]

Hello,bigredhemi. I would think it has to do with the bullet swaging process, it probably is easier bringing the jacket up to a near-point, as opposed to having to use a slightly longer core & precision forming that bit of lead to a perfect point..and there is a chance of it getting bashed out of shape in shipping & loading. By the way, back in the late 19th century, the target shooters found a hollow point to be more accurate at long range.

[HiBC]

The base of the bullet is every bit as important to accuracy as the point.The jacket begins as a cup.You can make an open base,or an open point.
The open point match bullet has a very small point,and a nice base.Plastic nosecones are relatively new.They seem to work well.

[bigredhemi]

OK - I just started to read about the swaging process and that makes some sense. http://rceco.com/img/RSBook1.PDF

If I read it right - and I may have to read it again - the swaging process requires that a small opening at the tip of the bullet remains.

BUT - what I'm trying to understand is - are hollow points inherently more accurate, and why, than the same bullet with the cavity tipped with a plastic point covering the hole like the A-Max?

[bigredhemi]

Let me ask it this way.

Everything else being equal...

Hollow point or HP with a nose-cone - which would/should be more accurate?

btw - last August experimenting
Marlin 336, 30-30, Hornady SST, H380, 8.5" x 11" high visability target, 10 rounds, 7 hit, 4 within 4-5" or so, other 3 towards the edges, with a 5 - 10mph crosswind. Not bad huh! (chambered them individually)

oops - forgot to state the range... 300 yards!

[PawPaw]

Originally Posted by bigredhemi

btw - last August experimenting
Marlin 336, 30-30, Hornady SST, H380, 8.5" x 11" high visability target, 10 rounds, 7 hit, 4 within 4-5" or so, other 3 towards the edges, with a 5 - 10mph crosswind. Not bad huh! (chambered them individually)

The Marlin 336 isn't generally considered a target rifle, but I'm convinced that they're a very accurate hunting rifle. Lots of deer killed by that platform. Lots of varmints dispatched as well. So, your question leaves some questions. Is the rifle scoped, or iron-sighted? Peeps or open sights? At what range? The accuracy you're talking about isn't bad for a novice shooter, and will certainly bring home the venison.

The heart-lung area of a standard whitetail deer runs about 9" in diameter, so any shot in that area will result in you having to sling your rifle and drag the deer out of the woods. The question becomes, at what range can you hit that 9" circle every time?

[bigredhemi]

Not to get too far off the original subject/question...

I only had my Savage .222 to practice with at the time so I decided to see what my 336 could do. So I threw on a 8-32x - 44mm sighted it in on 200 yards. It all looked pretty rediculous with that scope on it especially with the sunshades. Used about a 2 dot holdover when I turned to the 300 yard stands. After 3 shots I found the paper (was using a 80x spotting scope and a Caldwell rest). I know it's not a target rifle but I'm always excited when a product outperforms it's intended use and/or price point.

I wouldn't even consider a hunting shot with a 30-30 at 200 yards, let alone 300 yards. 4 out of 10 in a 9 inch group is not nearly good enough for any sane responsible hunter. The 336 could probably do a 9" group consistantly at200 yards, but I'm pretty sure I couldn't.

[Scorch]

Match bullets for rifles are hollow points because it keep the center of mass concentrated towards the geometric center of the projectile, and centered within the bearing surface of the projectile. Spire point bullets generally have the center of mass well ahead of the geometric center of the projectile, and well ahead of the center of the bearing surface due to the long nose of the bullet.

do know the hollow cavity improves the sectional density but the tip of the bullet is a leverage point and can easily be thrown off course if it's not perfect. What am I missing?

Sectional density is not affected by bullet design, it is simply the bullet's weight divided by the bore diameter. All bullets of the same weight and caliber will have the same sectional density.

Defects in the nose of the bullet can have a very small effect on accuracy, but even small defects in the base of the bullet will have a large effect on accuracy.

It seems that having a hollow cavity at the tip of the bullet would cause turbulence. And if the opening were even a tiny bit off, considering the high velocities, would have a negative effect on the trajectory.

Hollow point/open tip bullets do not cause turbulence, bullets in flight have a cushion of compressed air at the tip. Hollow points/open tips can have an effect on ballistic coefficient due to their profile. If the tip is off-center, it matters not what design the tip is, it will cause the bullet to spiral in flight.

I did have some time to experiment with some Hornady A-Max before all this global warming hit. I did pretty well with it out to 200 yards. Do you think the lightweight plastic point, while improving the SD, would also remedy any shortcomings the hollow point may have - or not?

The planet has been warming for the last 100 or so years, due primarily to the cyclic variation in the shape of its orbit. I was not aware that Hornady made the A-Max bullets 100 years ago.

The plastic tip on the bullet serves to protect the tip of the bullet as well as to increase the bullet's BC. The plastic tip has no effect on the bullet's SD.

[AlaskaMike]

The little bit I've read about this seems to indicate that the hollow point bullet is generally more accurate (all other things being equal) because most of it's mass is more to the rear of the bullet compared to other bullet types.

[Brian Pfleuger]

Originally Posted by Scorch

The planet has been warming for the last 100 or so years, due primarily to the cyclic variation in the shape of its orbit. I was not aware that Hornady made the A-Max bullets 100 years ago.

I think the global warming reference was tongue-in-cheek.... likely referring to cold and snow.


Much like the 8 weeks of temperatures 10 degrees below normal we've had in NY, which I often refer to as "global warming".

[Doodlebugger45]

PawPaw

He said he was asking about .222, 243, and 30-06, not the 30-30.

This was a good question and it was something I kind of always wondered about too. I never thought about the manufacturing process necessitating the hollow point on match bullets. But they work. And I guess the plastic tips work well too. But I've always heard the serious target shooters worrying more about the bullet base than the bullet tip.

[snuffy]

Your question about why a HP on match bullets is answered by; it's easier to form a precise point of copper gilding metal than an exposed lead point. The plastic tipped bullets have a nice sharp point which does the same thing, as long as that tip is exactly straight after it's placed on the front of the bullet, and stays there during loading and chambering!

Secondly, your observation that the HP would cause turbulence is wrong. The point of a super-sonic bullet doesn't really "touch" or come in contact with the air it's traveling through. There's a shock wave in front of the bullet that pretty well insulates the tip or point from the air. Once the bullet falls below super-sonic, the tip plays a part in accuracy and stability.

Tip irregularities don't affect the accuracy of the bullet as much as they do in the base. Put the same deep nick in the nose of a bullet, then put that same nick in the base, you'll see which affects the accuracy or group size real quick. Of course you'd have to do it to a series of 5-10 bullets, then shoot each at a target to see the difference.

[bigredhemi]

OK now it's starting to make sense to me why all the match guys go for the HPs. Thank you, everyone, for taking the time to respond.

Never considered the supersonic vs. subsonic effect on the tip as Snuffy & Scorch pointed out. And I was confusing SD with CG as Scorch pointed out. Does everyone agree?

There's a gun show close by this weekend and I'm gonna pick up some MatchKings and try to compare them to the A-Max. I said TRY because it's hard for me to tell sometimes if it's me or the load.

Please - anyone else have an opinion let me know!

(I live way too far away from the Equator...)

[HJ857]

I don't have a different opinion other than I'm in total agreement with Scorch's explanation. However, if you're testing bullets, I would strongly suggest adding Lapua Scenars if possible. My experience in the 6.5mm range was that Scenars kick the crap out of SMK's in every way and at a similar price point, or at least a similar price four or five years ago.

[Ideal Tool]

Hello, The British knew all about this hollow-pointing business way back in the late 1860's & early 70's. The .577 Snider first had a boxwood plug in it's nose, later the nose was closed by swaging, but the hollow remained..this was for improved flight. It is a fact that after the .577/.450 Martini-Henry was adopted, the new rifle was inferior in accuracy to the old Snider at long range.

[Rangefinder]

BUT - what I'm trying to understand is - are hollow points inherently more accurate, and why, than the same bullet with the cavity tipped with a plastic point covering the hole like the A-Max?

A couple things come into play here. One minor--(major when the difference between 1st and 2nd is measured in .001" group size). Lighter bullets can pull a slightly higher velocity while longer bullets are inherently more stable for distance. HP's give both. Also, the center of gravity is shifted farther toward the base of the bullet reducing point wobble and faster/better stabilization. The "plastic point", aka ballistic tip is generally there to assist/control bullet expansion upon impact when the bullet design is intended for hunting or varmints...

[Whisper 300]

For a more detailed explanation of Scorch's answer(quite correct,by the way)
pick up Brian Litz's book on long distance accuracy-he goes into very detailed yet quite easy to understand explanations of all the factors involved.

I am not shilling for the book but have found it to be a very good text without putting you to sleep with minutia.

Gary

[Rifleman1776]

A good question, this is a confusing issue.
My competition bullet of choice was/is the Sierra HPBT Match King. And it (I) shot very well.
My understanding of why hollow points are used in competition bullets is that the hollow front sorta cuts through the air in a symmetrical manner. It seems that, however good, a solid tip is it will always be slightly non-concentric/off-center and affect accuracy. In other words, no tip, no chance for non-concentricity.
BTW, I had never heard the term "open tip". Doesn't mean it doesn't exist, I just never heard it before. And Sierra does call this bullet "hollow point". They made it, I think they know what it is.
However, even knowing us gun nuts like to know all this stuff, I think musing over an issue like this is about as productive as contemplating one's belly button.
Don't sweat it. If it works, it works.

[Mike Irwin]

Testing has repeatedly shown that a perfect bullet base is FAR more critical to consistent accuracy than the bullet nose.

That doesn't seem to make much sense, until you understand how the shock wave forms around the bullet and how the base of the bullet is affected by drag.

Years ago when I was with Rifleman an author decided to do some tests where he started hacking up the nose of some spire point bullets with a saw and a file. Overall accuracy was affected a bit, but control group bullets with perfect noses and the hacked nose bullets were VERY close in overall group size.

He then started cutting on the base of the bullets in various ways, and groups opened up significantly.

[Wag]

What Scorch said was right on target, so to speak.

--Wag--

[amamnn]

Match rifle bullets are not made with hollow points. The jacketing process forms a meplat after completing the desired ogive of the jacket beyond the core material and is not intended to aid with mushrooming of the core material upon impact. A true hollow point will be formed so as to affect the core material and aid in expansion. Calling the excess jacket beyond the core a hollow point has become accepted only after so many ignorant people persisted in doing so, much like using the word "impact" as a verb....................

Over the years there have been match bullet improvement gimmicks such as meplat pointing tools and dies, meplat trimmers, and little tiny plastic nose cones for bullets. I have some several in my "fool me once" drawer. None of these can be said to have had a great impact upon the precision shooting world. One can see this monthly by looking at the equipment lists in the match results section of PS and other related publications, but like the engine tune-up in a can, people keep buying.

There may be something to be gained in trimming meplats for 1000 yard competition, but I've not seen a great rush to buy such devices after I got mine, and my experience with it was short as I lost access to the 1000 yard range in 1993. I have a lot less expeience with it than with the little plastic nose cones, which did not improve my aggregates at any range in any bullet of any weight in any caliber.

There is a lot more than pointy tips to match bullet uniformity and accuracy, and to really get an idea of what is possible with a hand built bullet made by an expert, you must buy from BIB, Bart's Precision Ballistics, and etc... To really understand the difference between these pills and "premium" offerings from Sierra, you need to be shooting a custom built high tolerance rifle with the knowledge and skill to produce aggregates in the 1/10 to 3/10 MOA range. This is not to belittle Sierra or other high quality mass produced bullets. They are head and shoulders above the standard hunting plinking pills, if one is more concerned with groups than with terminal performance, but neither they not the ultimate quality hand swaged one at a time crafted
BR bullets mentioned above mess with the meplats, because there has just not been any CREDIBLE evidence adduced by IMPARTIAL experimenters to convince these manufacturers to go to the added expense of pointing or trimming or adding little plastic nose cones. If there were much evidence one and then two and then they all would have done it years ago when this subject came up for the 4th or 5th time.

Just to be fair Don Lahr (Precision Ballistics) used to offer meplat uniforming at an extra charge since he sold bullets to a lot of longer range 6mm BR shooters. I don't know if he still does that since I never got any of his bullets trimmed that way and I have my own meplat trimmer in my FMO drawer. I think Don offered the service in the same way that Shilen and other BR and cutom barrel makers give out break in instructions. That is to say that they do more to make the customer happy than to actually affect the product.