The Firing Line Forums

Go Back   The Firing Line Forums > The Skunkworks > Handloading, Reloading, and Bullet Casting

Reply
 
Thread Tools
Old March 28, 2011, 06:48 PM   #1
hhunter318
Senior Member
 
Join Date: September 15, 2010
Posts: 145
Improving a Cartridge

I know all about fire-forming so that doesn't have to be discussed. But when creating a wildcat that includes minimizing case taper what has to be done? Does a cartridge diagram have to be drawn and sent to somewhere such as PT&G to get a reamer made? The round I'm wanting to work with includes necking down, shortening the neck, pushing the shoulder forward, blowing the shoulder to 40 degrees, and minimizing case taper. So what has to be done as far as the case taper goes?

Last edited by hhunter318; March 28, 2011 at 06:49 PM. Reason: to clarify
hhunter318 is offline  
Old March 28, 2011, 07:08 PM   #2
Jim Watson
Senior Member
 
Join Date: October 25, 2001
Location: Alabama
Posts: 10,598
Like you said, generate a drawing and have a reamer ground.

Or look in their catalog and see what has already been done.
Odds are there is something out there in your caliber on your case with minimum body taper, steep shoulder, and short neck. Hmm, sounds like a Gibbs to me. That way you could order from stock. Wouldn't be the .299 hhunter magnumb but it would save time and money.
Jim Watson is offline  
Old March 28, 2011, 07:29 PM   #3
FrankenMauser
Senior Member
 
Join Date: August 25, 2008
Location: 1B ID
Posts: 6,381
Quote:
So what has to be done as far as the case taper goes?
You have to draw it up, and get a reamer made.

And then have another undersized reamer made (based on fired cartridges), so you can have dies made.

It's almost always cheaper to use an existing wildcat.
I really wanted my own wildcat chambered in the M77 I have at the gunsmith right now. But... I couldn't justify the cost of reamers, dies, etc. Since I settled on a 6mm bore size, I took the path of least resistance. I'm having a standard .243 Win chamber and throat cut, but the gunsmith is engraving the barrel with a custom chamber designation. And, I'm having Quality Cartridge make some custom-stamped brass. It'll be made to .243 Win SAAMI specs, but will have my custom head stamp on it.

Of course, you could do the same with other actual wildcats.
__________________
"Such is the strange way that man works -- first he virtually destroys a species and then does everything in his power to restore it."
FrankenMauser is offline  
Old March 28, 2011, 08:27 PM   #4
Shoney
Senior Member
 
Join Date: February 21, 2002
Location: Transplanted from Montana
Posts: 2,311
Check with gunsmiths in your "greater" area. If they do not have the reamer, they can point you to some who might. They will also have good info where you can get the reamer made.

Also, if you have someone do the work with their own reamer, have them cut a set of dies with that same reamer.
__________________
I pledge allegiance to the Flag - - -, and to the Republic for which it stands….Our Forefathers were brilliant for giving us a Republic, not a democracy! Do you know the difference??? and WHY?http://www.wallbuilders.com/LIBissue...les.asp?id=111
Shoney is offline  
Old March 29, 2011, 01:56 AM   #5
FrankenMauser
Senior Member
 
Join Date: August 25, 2008
Location: 1B ID
Posts: 6,381
Don't use chamber reamers for dies. The natural elasticity of brass requires a smaller reamer to be used on the dies. If you don't, you'll be lucky to get three firings before the cases will no longer chamber, and you'll have neck tension issues from day one (unless you use a neck sizing die from a cartridge that will allow your wildcat to enter the die body without being resized, but is short enough to allow neck sizing).

Short version:
You need two reamers: A chamber reamer, and a die body reamer.
__________________
"Such is the strange way that man works -- first he virtually destroys a species and then does everything in his power to restore it."
FrankenMauser is offline  
Old March 29, 2011, 11:34 AM   #6
hhunter318
Senior Member
 
Join Date: September 15, 2010
Posts: 145
What i was brainstorming on was to take the original .416 Rigby case, neck down to .358, shorten the neck to .300, blow the shoulder forward to 40 degrees, and minimize the body taper. Is there anything close to that? It would have more capacity than the .338 Lapua since the Lapua was shortened from the original .416 case. The only downfall would be turning my own bullets due to the fact that nobody produces any .358 bullets for long range purposes. But this is no problem, my friend has a CNC lathe setup for turning bullets.
hhunter318 is offline  
Old March 29, 2011, 02:29 PM   #7
FrankenMauser
Senior Member
 
Join Date: August 25, 2008
Location: 1B ID
Posts: 6,381
I don't know of anything close to that, but I'm sure it's been done. A gunsmith or reamer company may have a list of available reamers for you to take a look at, if you want to check.
__________________
"Such is the strange way that man works -- first he virtually destroys a species and then does everything in his power to restore it."
FrankenMauser is offline  
Old March 29, 2011, 04:24 PM   #8
Unclenick
Staff
 
Join Date: March 4, 2005
Location: Ohio
Posts: 9,991
Look at page 5 under Alterations in Dave Manson's catalog to get cost ideas. Call and talk to Dave about your project for some idea of how best to approach it.

The reamer makers have some fill-in-the-blanks drawings for specifying the reamer. The computer program QuickDESIGN will let you start with an existing case (or create a new one) and modify it to your dimensions and automatically generate reamer drawings from your cartridge spec.

If you are going to look at making your own lower BC long range bullets, you'll be in for some fun, not the least of which will be choosing the twist rate for your rifling. That can be done with the stability calculator on the JBM ballistics site. You can design the bullet and cartridge in that QuickDESIGN program and export them to QuickLOAD to estimate starting load data.
__________________
Gunsite Orange Hat Family Member
CMP Certified GSM Master Instructor
NRA Certified Rifle Instructor
NRA Patron Member

Last edited by Unclenick; March 30, 2011 at 09:14 AM. Reason: Typo fix and added info
Unclenick is offline  
Old March 29, 2011, 07:04 PM   #9
hhunter318
Senior Member
 
Join Date: September 15, 2010
Posts: 145
Thanks for the infor Unclenick! Very helpful.
hhunter318 is offline  
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 02:46 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
This site and contents, including all posts, Copyright © 1998-2013 S.W.A.T. Magazine
Copyright Complaints: Please direct DMCA Takedown Notices to the registered agent: thefiringline.com
Contact Us
Page generated in 0.07809 seconds with 9 queries