Meplat pointing

[JamesBailey]

So the textbooks say that making the blunt meplat less blunt improves the form factor of a bullet, thereby improving its BC and resulting external ballistics. Small bullets are especially helped because their meplat to caliber diameter ratio is high (for example a 77gr SMK has a meplat of 0.064" to its .224" diameter, or .29 meplat to caliber, vs a 175gr SMK's .21). This is of interest to me because I reload and shoot the small calibers - .224 and .264.

Using a formula that estimates form factors, I calculated that if I could reduce a .224 and .264 meplat by 0.02, I could improve the form factor by ~7%. A 7% improvement in the form factor reduces the wind drift of a 77gr SMK .224 at 600yds by 8% and reduces the wind drift of a 142gr SMK .264 at 1000yds by 11%. Trajectory is also flatter. Or so the text book says.

My questions are:
(1) does anyone have any comments on meplat pointing? Any real world ballistic data?
(2) does anyone have any tools to recommend for meplat pointing? Midway has a die, but it costs big bucks ($200+).

thanks for any advice.

 

[jimbobborg]

SMKs are JHPs. Short of closing the hole, what are you actually accomplishing with this?

Jim

 

[Oliveralan]

Your calculations are on line with what is generally accepted (around 7% increase in BC) now BC itself is a flawed concept but we're not discussig that here. It is definetely beneficial, but requires a lot of extra work and expensive gear. The Whidden (sp?) bullet pointing system is the only one I'm aware of off the top of my head.

I believe for f-class it could be useful, but it's a high cost and lot of effort involved for a relatively low benefit. It's up to the individual if it's worth it
to them. I may look into it sometime, but so far I've been doing fine in f-class without one IMO a Sinclair f-class bipod is a better use of the $200. If you have $400, then get the die too I suppose

while better BC is nice, in the LR game, as I'm sure you know, consistency is key.

 

[E.Shell]

SMKs are JHPs. Short of closing the hole, what are you actually accomplishing with this?

The ONLY reason they're hollow points is that finishing the jacket at the nose is a better method for accuracy than closing it at the base.

The accomplishment is that by pointing the bullets, we do away with the deterministic vertical variation caused by the predictable variations in BC by bringing all the bullet points into uniform configuration. Closing the hollow point is a secondary effect and serves no purpose.

Vertical dispersion at long range is usually associated with velocity variation, often a result of poor mating of components or bad neck tension. The bullet brings it's own problems to the table. This variation is admittedly small, but as distances increase they can become critical and stack up, so we must strive to control as many variables as possible.

...while better BC is nice, in the LR game, as I'm sure you know, consistency is key.

Yup, like Oliver says, the actual improvement (albeit small) to the BC is definitely a benefit, but the real benefit does lie in making them more consistent with each other.

The meplat trimmer is another approach to exactly the same issue, it just makes the BC uniformly degraded instead of uniformly improved as does the pointing tool.

 

[10xclean]

Another simplier solution

I am all about simplifying things.

A-MAX bullets with the plastic tips. Single load them so not to damage the tips. The 80 gr bullets are great for 600yards high power competition.

 

[JamesBailey]

I am all about simplifying things.

A-MAX bullets with the plastic tips. Single load them so not to damage the tips. The 80 gr bullets are great for 600yards high power competition.

Yes, the AMax are nice and I enjoy the 80grainer; problem is, they aren't mag length like the 77gr SMKs. Plus I don't think Hornady's AMax at .264 is all that great.

I was hoping someone had a $20 solution to the pointing issue, because I don't want to spend the $200 on the dies.

Attached below is a example of the before and after. This basically works for any bullet with a meplat, which is all of the VLDs and OTMs (i.e. just about anything from Sierra, Berger, Lapau, and JLK). You do need to buy different guides for the different calibers, which adds another $50 per caliber

 

[jimbobborg]

Too bad you don't know a bunch of people who would be interested in using this contraption to do batches and pass it around...

Jim

 

[fa18hooker]

John Widden (National Long Range Champ) sells a pointing system, but as you've discovered, it's expensive. German Salazar (http://riflemansjournal.blogspot.com/) has a great article regarding meplat trimming and pointing...he points his.

 

[JamesBailey]

John Widden (National Long Range Champ) sells a pointing system, but as you've discovered, it's expensive. German Salazar (http://riflemansjournal.blogspot.com/) has a great article regarding meplat trimming and pointing...he points his.

Thanks, that is a good site and article. Here is his specific piece on pointing:

http://riflemansjournal.blogspot.com/2009/07/reloading-whidden-bullet-pointing-tool.html

 

[4MDGunRights]

From what I read on this sticky thread on the sniper's hide, the loss of BC by just trimming all of your meplats to be consistant is minimal which is offset by the improvement gained by consistancy between bullet to bullet. The tool to sharpen the meplat is very expensive and doesn't give you much benefit for the price. I found the reloading tips on this site to be very helpful.
http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=1699588#Post1699588

 

[JamesBailey]

From what I read on this sticky thread on the sniper's hide, the loss of BC by just trimming all of your meplats to be consistant is minimal which is offset by the improvement gained by consistancy between bullet to bullet. The tool to sharpen the meplat is very expensive and doesn't give you much benefit for the price. I found the reloading tips on this site to be very helpful.
http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=1699588#Post1699588

Interesting comments on that link. I especially found the last post on that thread interesting, as it jives with data that I have observed: Berger and Sierra bullets show good to very good consistency, whereas the Hornady's can have a lot wider ES. I have seen that especially with the Hornady 75gr HPBT vs the Sierra 77gr SMK. I don't have any experience with the Lapua bullets, so I don't know how they compare to the Yellow, Green and Red boxes.

I will probably pass on pointing and/or trimming at this time and stick w/ Sierra and Berger bullets.

 

[hylomar]

11 time NRA high power rifle champion David Tubbs meplats his bullets.
http://www.davidtubb.com/tcom_images/reloading/bmu_one.html

He has created a kit to help you do the same. He sells a varity of calibers, .224, 6mm, 6.5mm, 7mm, .308, and .338. Sorry all you 50 cal guys. All for the resonable price of $50 per caliber.
http://www.superiorshootingsystems.com/Reloading_Tools-BMU.html

 

[MDCXD]

I have been looking at the Widden bullet pointing dies, and will probably buy one soon. My concern is, I will spend a couple of extra hours loading a cartridge that is capable of shooting a 1/4 minute, then load it in a 1/2 minute rifle.

 

[DZ]

I have been looking at the Widden bullet pointing dies, and will probably buy one soon. My concern is, I will spend a couple of extra hours loading a cartridge that is capable of shooting a 1/4 minute, then load it in a 1/2 minute rifle.

... and then have the trigger yanked by a 5 minute shooter

 

[JamesBailey]

I have been looking at the Widden bullet pointing dies, and will probably buy one soon. My concern is, I will spend a couple of extra hours loading a cartridge that is capable of shooting a 1/4 minute, then load it in a 1/2 minute rifle.

Mike -
let us know how the bullet pointing goes.

 

[JamesBailey]

... and then have the trigger yanked by a 5 minute shooter

Low blow, very low. Me like.

 

[MDCXD]

Mike -
let us know how the bullet pointing goes.

I will. I guess the next step will be case annealing, I will probably spend so much time reloading. I won't have time to shoot. but I will have some high quality ammo.