".280" not a 280...243, 220 Swift? Ideas?

[19_A_CPT]

Did some trading for what was supposed to be a 280. I noticed the small caliber when meeting with the guy but just thought maybe my eyes were playing with me. Got it home and a .223 sticks in the end of it and my boresighter (30-06) slides into the chamber so seems to be a .473. Base. How to tell? 

I assume its a 220 Swift or a 22-250, but should I count out the 243 yet? Anyway to be sure aside from taking to a gun Smith and chambering these rounds?

[nightrunner]

Safe to assume it’s some sort of custom gun with no markings whatsoever?

Edit to add: If you think it’s .30-06 based, I would look more at .22-250 or .25-06

Edited August 3, 2020 by nightrunner

[19_A_CPT]

2 minutes ago, nightrunner said:

Safe to assume it’s some sort of custom gun with no markings whatsoever?

Correct.. build on a 1893/1916 Spanish Oviedo Mauser.. Only lettering on the barrel is SHIP 5 79 on the bottom side... no other hints 

[RED333]

https://www.brownells.com/gunsmith-tools-supplies/barrel-tools/barrel-chamfering-accessories/cerrosafe-chamber-casting-alloy-prod384.aspx

https://www.sinclairintl.com/guntech/casting-your-chamber-using-cerrosafe/detail.htm?lid=16061

You can do this your self or pay a smith to.

[Sunfish]

6mm-06 was pretty popular for a time. I have one and it has a 30 degree shoulder angle.  If a 06 case will go in it you could fire form it without a projectile and measure out what you get 

[gregintenn]

Cerrosafe chamber cast and calipers.

[leroy]

1 hour ago, gregintenn said:

Cerrosafe chamber cast and calipers.

Ding... Ding... Ding... " We have a winner "..!  The only " safe " way ta tell...

leroy.

[19_A_CPT]

Anybody yall would recommend in the Dickson area that would/could do it reasonably? 

I am going to chamber a 243 empty tonight and see how we turn out. I think the 30-06 is probably going to extend too long and will based on a 308 casing rather than the -06.  I may be wrong, as i have before, but just seems like the -06 parent case will be too long for my chamber. Originally they were a a 7x57 Mauser and many were converted to 308, so hopefully its a popular offshoot of it. 243 would be ideal, but with my luck, its a 22 caliber Bubba designed in his back room. 

 

[gregintenn]

Were it a 243, I would think a .223 bullet would drop freely down the barrel. I expect it is a .223 bore from your picture. There are many .223 chamberings, but a 22-250 would be a good first guess.

[Handsome Rob]

8 hours ago, gregintenn said:

Cerrosafe chamber cast and calipers.

This is literally the only way to know for sure. 

Being an old mauser, rechambered literally anytime in the last 100 years, you'd be silly not to. There were many tens of .21 & .22 caliber Wildcats designed and chambered in the '30s thru the '70s.

My guess (&that's all it is) judging from the age of the gun & what was popular in the 'golden age of tinkering' when everyone was chasing speed, is it could very well be a. 223 wildcat based on the .250-3000 Savage.

[Handsome Rob]

Just to give you an idea.....

These are all 'recognized' chamberings. Im sure there are as many home made wildcats.....

Edited August 3, 2020 by Handsome Rob

[19_A_CPT]

Got it figured out with the help of an old friend. Its a 22-250. 

Thanks for the thoughts and help. Not the 280 i had planned for but a fun round nonetheless. And cheaper to shoot! 

Will probably let the wife and kids take it over . 

[RED333]

https://en.wikipedia.org/wiki/.22-250_Remington

The .22-250 Remington is a very high-velocity (capable of reaching over 4000 feet per second), short action.

WOW that is a ripper!!!

[nightrunner]

5 hours ago, RED333 said:

https://en.wikipedia.org/wiki/.22-250_Remington

The .22-250 Remington is a very high-velocity (capable of reaching over 4000 feet per second), short action.

WOW that is a ripper!!!

It’s a .30-06 necked down to a .22 basically. It ought to be fast

[Handsome Rob]

5 hours ago, nightrunner said:

It’s a .30-06 necked down to a .22 basically. It ought to be fast

It's actually a .250-3000 necked down to .223.

[Capbyrd]

22 hours ago, 19_A_CPT said:

Anybody yall would recommend in the Dickson area that would/could do it reasonably? 

 

I know you already figured it out.  But do it yourself.  It's very simple, nearly impossible to mess up and fun! 

[Mowgli Terry]

I'd also make sure there was no problems with the action. The 22-250 is pretty hot for that particular action. Problems could be set back or excessive headspace, Standard stuff on any built up rifle.