removing lead tip and B.C.

[RW]

Say you have a rifle that has to much throat for for a hunting style bullet with a exposed lead tip, such as a Sierra spitzer boat tail. Would it be safe to assume that the jackets are relatively consistent so that you can remove the exposed lead so as to be able to seat the bullet closer to the lands. And how much would the B.C. be changed and how would you determine the corrected B.C.? I'm sure that it is not the same for every style and calliber bullet. I have done this in the past with a short magazine and longer throat. I now that it will alter bullet terminal performance. I have achieved good accuracy with what I call short bullets but I was wondering about the B.C. Would chronographing the bullet at the muzzle and then doing a drop test at longer yardages reveal the corrected B.C. Than You, Ron

 

[spclark]

Cutting the lead SP off a hunting bullet will do absolutely nothing towards changing the lands contact point of the jackets up closer to the bearing surface.

They're hunting bullets, being fired thru a hunting barrel, right?

Just load 'em & shoot 'em. If you kill anything it's not because you improved anything ballistically when you cut their noses off.

 

[savagedasher]

Most hunting bullets take a different seating depth because of their shape . When you use a case like 308 that takes 2.80 for max seating lingth ' a target bullet with 168 GR will fit with no problem . Put a 120 GR hunting bullet seated at 2.800 and you wouldn't be able to close the bolt because of the bullet shape. 2.800 is the normal reference for magazine length. Reloading books that bullet company's make normally list the change .. Sierra book 308 w All 175 and180 GR the coal is2.800 the round nose is2.710 or .090 less the 150 GR coal very from2 .775 to as short as 2.500
Larry

 

[RW]

So let me get this right ; If you remove say 30 thousands of the tip allowing you to be able to seat your bullets out that much farther it won't change the bullet to bearing surface in the barrel? It is a hunting rifles with trued 700 action and custom barrels. I'm scratching my head as to why if you seat you seat your bullets out farther that doesn't change any thing!
I have a custom 375 H&H that when I sand the lead tips off and seat the bullets closer to the lands it has a definite improved grouping and I was just wondering how much that would affect the B.C. I have killed more than its share of animals out to 350 yards but I was thinking about shooting some targets out a little farther! By the way the shortened bullets weigh about 5 grains less. I didn't think it was that stupid of a question. Ron

 

[Spike A]

ron,
i am a little confused, why do you need to take the lead tip off the bullet to load it closer to the lands? The bullets will not touch the lands till the o-give on the bullet which is different on each caliber and bullet weight and brand. most shooters will load just off the lands and never touch the bullets. myself i hunt with a browning a-bolt in 308, and i load that just off the lands but it was a few thousands too long to fit in the magazine so i seated it just deep enough to fit in the magazine as i would like to be able to use it (mind you it will still shoot sub moa all day long). Now in my 223 the sweet spot for that is too long for the magazine but i am content hand feeding it for much better accuracy for what i am doing with the gun. so to answer your ? i guess i would say filing down the bullets will achieve absolutely nothing besides making the length less consistent than they already probably are, just load them out longer to what ever you would like, i would also like to see how your accuracy improves on your h&h without taking any off the ends.

 

[spclark]

Shaving bullet noses doesn't change where those bullets first contact the barrel's lands at all. Seating bullets out farther than what's suggested in various reloading manuals DOES change the dynamics of how bullets can perform down-range. That's a well-accepted technique for maximizing ballistic performance among those who choose to seek that goal.

If you shave bullet noses (tools are made for this called meplat trimmers; meplat is the ballistic term for the most forward part of a bullet's design) that are intended to be loaded for magazine-feeding rifles then yes, shaving meplats can allow those bullets to be seated out farther which lessens their 'jump' or the distance traveled until they first encounter the rifle bore's lands.

Yours isn't a stupid question at all (none are unless you already know the answer!) and I apologize if my reply gave you that impression. I may have misunderstood something in your original post as you didn't mention whether you're loading for a single-shot rifle or rather for magazine-fed rounds.

Trimming meplats - depending on how much you trim them - has been described as decreasing BC around 5%. To gain some or all of that lost BC back some go another step & re-point the shortened meplats using special bullet tip dies, available from several sources. I doubt that would work well on typical soft-pointed hunting bullets as those most commonly 'tipped' are hollow-pointed target rounds where the lead cores aren't close enough to the open-meplat jacket tips to be affected by these tuning operations.

 

[snert]

If the bullets are loaded to maximum MAG length and are still not close enough to the lands, then lopping off the end would make it fit the mag and allow longer seating...

Not suggesting that, but...

 

[Spike A]

well you learn something new every day clark. i know i am very in experienced in reloading to many of you. so i have never heard of trimming bullets and re tipping them. although most of my knowledge is with single shot guns and what not that has intrigued me and now i will be in search of more information on this haha. so thank you clark for stretching my knowledge.

 

[spclark]

Spike A, it's my core philosophy to learn something - anything - new each day.

Sharing what I've picked up along the way with others who are tuned in to the same channel (pretty much every forum member here fits under that umbrella!) is a bit of what keeps me coming back here.

http://www.6mmbr.com/MCRMeplat.html

http://benchrest.com/showthread.php?74237-Meplat-trimming-amp-bullet-tipping

http://www.busseltonrc.com/Articles/Bryan%20Litz/Meplat%20Trimming.pdf

http://www.6mmbr.com/bulletpointer.html

 

[Bryan Litz Ballistics]

Ron,

I get what you're saying, it's about getting closer to the riflings while being able to mag feed as SP Clark stated. This is perfectly reasonable, I think some others missed the key: mag feeding.

To answer your question, it depends on the specific lead tip and it's shape. If I had to throw a guess out there, I would estimate 7-8% BC loss for blunting the nose, and another 2-3% for the weight loss. I think a total of 10% total reduction is probably close to what you're looking at.

Take care,
-Bryan

 

[Puzzaz01]

I agree with Bryan, I think a lot of the responses were from not fully comprehending your question of the bullet over all desired length not fitting into your magazine.

 

[Spike A]

I understand the need / want to be able to mag feed .. To me I guess instead of all of that work and worry over b.c. I would look into another bullet that might have a different o-give to meet your requirements.

 

[savagedasher]

What the BC difference can be figured . I have my doubts that lead would hold it shape with speed..
Hornady found their tips was a problem. Larry

 

[RW]

Thank you all that replied. And thank You Larry because you addressed my original question of how much the B.C. would change as I had heard that the lead tip is not that important as it may or may not be in place as the bullet is fired and that the heal of the bullet is much more important than the tip. I used the data for COL from a manual in the past, the last time about in the late 1970's before I started measuring my COL in relation to the how far off or close to the lands. In such calibers as the 375 their is not that many choices in bullets, especially if you rule out the HARD bullets! Normally as the caliber go up so does the jacket thickness. I really enjoy to shoot the 375 and have found that it doesn't ruin a lot of meat as much as a very high velocity cartridge and I own most of them from 25 caliber on up with a lot of experience with them. Believe me shooting something such as a Barnes or other hard bullets on elk is way over kill with results of clean pass thru, not something you would want unless you were shooting African Game. I wish that Berger would make a bullet for it such as a VLD, I have tried most all of the bullets available and the 300 gr. sierras have been great if I can get the closer to the lands,Ron