Jump to content

Making your own calibre


Recommended Posts

Never reloaded my own, but I was bored to death at work today and thought it'd be great if I could neck down a 22-250 case to fit a .17 bullet.

 

Realistically, how hard is this? Including what you'd have to do to get a gun/barrel that would take this round.

 

And would I have to put a variation through for a 17-250 even before I start?!

Link to comment
Share on other sites

A .308 necked down to 6mm? Naah, it'll never take off! :hmm:

 

(That's exactly what Winchester did when they created the .243 Win. They originally had it down to .257, but changed it to .243 to compete directly with the .240 Remington (AKA 6mm Rem). And the 6mm Rem is a .257 Stevens necked down to 6mm. The .257 Stevens is a 7x57 Mauser necked down to .257- not much new in this game.)

 

There is no reason you couldn't neck a 22-250 down to .17, but it'll be grossly over bore, throat erosion will be horrendous and you'd be lucky to get 200 fps on the .17 Rem.

 

The .17/.223 wildcat is generally regarded as the most case capacity you can stick behind the .17 caliber bullet and get a worthwhile return, and even that doesn't show much improvement on the .17 Rem.

 

But there's always room for experimentation and experimenters in this world. Let us know how you get on- especially if you manage to crack 5000 fps!

Link to comment
Share on other sites

Most current cartridges are only necked down or necked up versions of something else, I would imagine that what you suggest has already been tried by someone somewhere. Probably that guy over there with one eye and half his fingers missing.

Edited by Vince Green
Link to comment
Share on other sites

The 20-250 is considered very overbore, so the 17-250 would be very much overbore. However, with a LONG barrel and some of the 30 gr golds (or 37 gr VLD if you can find some) you could probably get some impressive speeds for the big bullets.

 

That said, look at the 17 predator and rocky mountain varmint hunter. He's taken a 223 and blown it out a bit to shoow 30 gr golds at 4100.

 

http://www.rmvh.com/17PDanC.htm

 

Additionally, if you want to look at other big 17 caliber cartridges then there is the 17 PPC and 17 BR. Both are slightly bigger than the 17 pred. There is also the 17-204 which is about the same size as the 17 pred.

 

Necking down isn't hard to do. For a 22-250 you'd need a 17 and 20 caliber bushing/die at the minimum. Something in the 0.185" would also be a good intermediate step also. Of course you'll have to turn the necks when you're done if you plan to actually shoot it.

 

Thanks,

Rick

Link to comment
Share on other sites

Why would you want to?

 

Isn't there enough calibres around to choose from?

 

Surely there must come a point where a bullet is pushed too fast? maybe there isn't I don't know enough about rifle reloading to be sure.

Link to comment
Share on other sites

Thanks guys for the replies. It was really just out of interest.

 

One question that wasn't answered... How hard is it to get a gun to chamber a .17-250? Is it really as simple as finding a 22-250 with an interchangeable barrel and changing it with the same make of gun barrel that's a .17?!

Link to comment
Share on other sites

High velocity doesn't come from necking down a big case. The real experimental ultra HV stuff has small very dumpy cases because the ideal combustion needs a case as close to spherical as they can reasonably make it.

 

You can only get so much gas down a barrel before the bullet leaves it. The idea that big case equals more power is a throw back to the black powder days and is the origin of the word magnum as applied to ammunition. A magnum is a double sized champagne bottle. Modern powders don't like a long case because it interferes with the burning of the charge.

Link to comment
Share on other sites

As I have posted before...

 

A .50BMG necked down to a snazzy little .22

 

neckdown.jpg

 

Whilst searching the net I found the actual name of this round. It is no joke, look it up:

 

".22 Eargesplitten Loudenboomer"

 

It sounds like this has actually been fired then...

Link to comment
Share on other sites

While there are thousands of calibres out there, there is always room for improvement.

 

James Calhoon http://www.jamescalhoon.com has been producing 1.19 calibre rifles for years. Mainly based on Hornet and .223 rounds, they are extremely good for varminting at close/medium range. James also makes excellent, double cavity, jacketed bullets in .19 caliber.

 

Small Caliber News http://www.smallcaliber.com has some excellent articles on small calibre wildcats. In particular, the articles on Russ Lucas are very good. Russ is well known for his .14 caliber which is superb on rabbit sized game.

 

The late Bill Eichelberger was well known for .14, .12 and .10 caliber offerings and I was privileged enough to meet Bill, and shoot a .10 caliber a few years ago.

 

Personally, I think the micro-calibres have a place in vermin shooting in the UK and I am surprised they have not got a larger following (excuse the pun). Here in the UK we have very small plots of land to shoot over, when compared with the USA etc, and small, hyper-fast, bullets mean super flat shooting and virtually no chance of ricochet. Add to this the fact that they do not travel very far when compared to rounds like 22lr/17hmr (the more normal vermin rounds) and you have a good, safe calibre.

 

I developed my own calibre a couple of years ago (17x39) and can give anyone who is interested any info they need on how to start off.

 

If I started again tho, I would cut out a whole load of aggro and buy a G2 Contender and then have a suitable barrel made up to my requirements!

Link to comment
Share on other sites

As I have posted before...

 

A .50BMG necked down to a snazzy little .22

 

neckdown.jpg

 

Libs thats not a .50BMG case, just a .378Wby case necked down to .224....

Look up the .338 Talbot..since that's about as small as you can neck down a BMG case without it becoming a smoothbore in 10 shots!

 

 

I have designed and had produced my own reamer, similar to the factory spec .300 Lapua or 30/338 (6mmbr will show you all the steps involved). Its a great 'little' round and is starting to show good promising groups. Looking forward to testing it near the mile mark next weekend!

Link to comment
Share on other sites

The UK's first and, I believe, only 20-250 wildcat was built for me by Neil McKillop.

The 22-250 has been necked down to 17 calibre before. It's known (I kid you not) as the .17 Flintstone Super Eyebunger. Published data for it shows only a 300 fps increase in velocity over the 17 Remington, despite using over a third more powder.

I really feel that the 17 Rem is the ideal high velocity 17 cartridge. The 17-250 wildcat is so overbore as to be pointless.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
 Share

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...