Long Range Hunting Online Magazine


Go Back   Long Range Hunting Online Magazine > Rifles, Reloading, Optics, Equipment > Rifles, Bullets, Barrels and Ballistics


Reply

Plastic tips?

 
LinkBack Thread Tools Display Modes
  #1  
Old 02-12-2012, 11:26 AM
Platinum Member
 
Join Date: Nov 2005
Posts: 1,082
Plastic tips?

Obviously plastic tips make bullets longer, but what is their effect on required twist?

Intuitively I would think that a heavy nose is better for stability. After all a plastic tip added to a hollow point bullet moves the CG rearward causing more instability...but I have heard that this is not the case.

edge.
Reply With Quote
  #2  
Old 02-12-2012, 12:56 PM
Platinum Member
 
Join Date: Jan 2004
Location: Blackfoot, Idaho
Posts: 8,112
Re: Plastic tips?

edge,

Here are my unscientific observations based on the repointing project... Opinions only

Plastic tips seem to have been developed to prevent point deformation of cartridges in the magazine after the first shot. This then caught on as they are pretty sexy looking and caught on with shooters

Plastic tips are simple to form and incorporate into bullet forming. They are very light and my opinion is that they contribute very little to bullet weight or stability considerations.

Plastic tips are very uniform thus bullet to bullet bc should be very consistent.

Plastic tips are relatively blunt thus bc will be lower than if the same weight hollow point bullet had a meplat diameter of 0.025"

The the repointing project trims the jacket back a specific amount, removes the plastic stub and inserts a brass tip with a meplate less than 0.030" and a weight of around 11 grains with a significant increase in overall length length.

The final bullet weight is increased a few tenths under 10 grains.

BC is increased by a published and real world tested just under 0.500 to a calculated estimate 0.660. Field testing is sporadically underway with definite indications of significant bc increase.

Out of my 8 twist barrel @ 3500 MV stability doesn't appear to be an issue.

However, process tolerances definitely make a difference.

Here's a pic to feed your mind processing a bit.

The 159.8 grain repointed bullet compared to the 150 Ballistic Tip and a 195 grain Wildcat.
__________________
I may be the slowest guy on the mountain . . . . but . . . . I'm on the mountain!
Reply With Quote
  #3  
Old 02-12-2012, 02:42 PM
Platinum Member
 
Join Date: Nov 2005
Posts: 1,082
Re: Plastic tips?

Wow, how cool are those

My problem is selecting a bullet for a rifle with a slow twist.
If I use a Miller stability program I need to know if the plastic tip is included in the OAL or do you only use the copper portion OR do I need to actually add some factor to the tip length to figure the correct twist?

edge.

As an afterthought, have you tried to reshape the Accubond tip in the lathe?
Make a sharper point by shaving the tip and jacket back and leaving the OAL unchanged?
Reply With Quote
  #4  
Old 02-12-2012, 04:24 PM
Platinum Member
 
Join Date: Aug 2003
Location: NC, oceanfront
Posts: 3,291
Re: Plastic tips?

It's a good question edge, and I agree with your reasoning.
It does seem like plastic tipped bullets would be less stable(given CG to CP). But they are actually a bit MORE stable(somehow).
They don't seem to be any lower in drag either, as their BCs are same or worse than non-plastic-tipped..

Maybe Bryan Litz would help with understanding of this.
Reply With Quote
  #5  
Old 02-12-2012, 07:29 PM
Platinum Member
 
Join Date: Jan 2004
Location: Blackfoot, Idaho
Posts: 8,112
Re: Plastic tips?

Quote:
Originally Posted by edge View Post
As an afterthought, have you tried to reshape the Accubond tip in the lathe?
Make a sharper point by shaving the tip and jacket back and leaving the OAL unchanged?
Yes I reshaped the tip on the lathe but none of the variations I tried panned out. They were not pleasing to look at, bc calcs said it wasn't worth the effort.

The brass tips make a definite change. Plus they perform terminally as identical as I can determine as the original NABs and BTs.
__________________
I may be the slowest guy on the mountain . . . . but . . . . I'm on the mountain!
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes


Similar Threads for: Plastic tips?
Thread Thread Starter Forum Replies Last Post
weight of plastic vtr stock jimbothepunk Rifles, Bullets, Barrels and Ballistics 0 11-16-2010 01:02 AM
How good are you? (Some plastic cartridges) AJ Peacock General Discussion 9 09-15-2008 11:15 AM
Long, Plastic Gun Case stephen newberry General Discussion 1 07-30-2007 04:44 PM
IMR Plastic Bottle Lot #s Buffalobob Reloading 11 12-07-2005 07:45 PM
Need Remington SA BDL Plastic Stock Guns For Sale 3 01-02-2003 01:38 PM


All times are GMT -5. The time now is 11:47 PM.


Powered by vBulletin ©2000 - 2014, Jelsoft Enterprises Ltd.
Content Management Powered by vBadvanced CMPS
All content ©2010-2014 Long Range Hunting, LLC