Shotgun conversion to non-shotgun

Mitch R · March 26, 2002, 01:41 PM

I'm pretty timid, but sometimes I muster the courage to jump in with both feet and bring up something outlandish. Hopefully I won't get laughed out of Dodge for it. =)

Would it be possible (regardless of whether it's silly) to convert a shotgun to a non-shotgun chambering? Could a .410--presumably a European-style short chamber, if those come in .410-- be made into a .41 magnum?

Or possibly even (I can hear the screams about pressure already) a .410 into a .416 Remington mangnum?

I'm curious how you think these might feed from the magazine... or for that matter if a rimless (belted or otherwise) cart like the .416 would be usable in a break-action.

Keith J · March 26, 2002, 02:39 PM

Shotgun loads were typically rated internally for ballistics in LUP, Lead Units of Pressure. Most centerfire rounds were ballistically (internal) measured using CUP or Copper Units of Pressure.

It takes little imagination to know the difference in pressure. Feeding from the magazine and rimless extractors would be the least of your worries.

Feeding is going to be rough on a pump or semi-auto without any modification. An extractor for a rimless cartridge break-open action is much easier.

C.R.Sam · March 26, 2002, 04:52 PM

Quite a few break top singles and doubles have been converted from shot to rifle by inserting a rifle barrel inside of the shot barrel. They come out muzzle heavy and heavy all over but it is quite doable. Recent sightings have been in .444 Marlin, .405 Winchester, 45-70.

Sam

James K · March 26, 2002, 06:25 PM

Shotguns are generally designed for low pressures, in the 20,000 psi range; many modern rifle cartridges run to 60,000 and up. No matter how the measurement is done, shotguns were not designed to stand up to rifle pressures and will not do so.

As Sam says, many break open shotguns have been converted to fire rifle cartridges by using liners. Companies like H&R long made single shot break open rifles on the same frame as their shotguns, but all of those have been for moderate pressure loads or were beefed up substantially. IMHO, a .416 Rem Mag in the typical .410 shotgun would be a hand grenade waiting to go boom and take some portion of the shooter's anatomy with it.

Jim

Mitch R · March 27, 2002, 03:13 PM

"...a .416 Rem Mag in the typical .410 shotgun would be a hand grenade waiting to go boom and take some portion of the shooter's anatomy with it."

And that's without considering how much material would have to be removed from the chamber (in this case, the barrel) to get the .416 to fit. Perhaps not too much, given the thickness of a plastic shell, but still...

OK, so that was a bad idea.

How does pressure affect the barrel itself? Supposing I found a .41 magnum action from something else, would a rifled .410 barrel be appropriate? It'd be conveniently sized, if nothing else...

James K · March 28, 2002, 06:27 PM

Same problem. Shotgun barrels are not made of the same quality of steel as are rifle barrels and are not made to take the pressure of firing rifle ammunition.

Unless this is just one of those "what if" questions, I confess I can't see what you are thinking of doing. There are plenty of reasonably priced high power rifles available without trying to make one out of a cheap shotgun. The cost of a Remington .416 would be high, but not as high as the cost of replacing a head or eyes, given that spare parts are scarce.

Jim

Mitch R · March 29, 2002, 12:47 AM

The question was academic-- one of those "just seemed like a good brainstorm at the time" kind of things. It's not like I have a Blackhawk and a .410 that I was actually intending to hybridize.

Which, from the sound of things, is a good thing.

Thank you for the advice.

March 26, 2002, 01:41 PM	#1
Mitch R Junior Member Join Date: June 13, 2001 Location: New York (no, not the city) Posts: 3	Shotgun conversion to non-shotgun I'm pretty timid, but sometimes I muster the courage to jump in with both feet and bring up something outlandish. Hopefully I won't get laughed out of Dodge for it. =) Would it be possible (regardless of whether it's silly) to convert a shotgun to a non-shotgun chambering? Could a .410--presumably a European-style short chamber, if those come in .410-- be made into a .41 magnum? Or possibly even (I can hear the screams about pressure already) a .410 into a .416 Remington mangnum? I'm curious how you think these might feed from the magazine... or for that matter if a rimless (belted or otherwise) cart like the .416 would be usable in a break-action.

March 26, 2002, 02:39 PM	#2
Keith J Senior Member Join Date: December 15, 2000 Posts: 469	You are correct 'bout pressure Shotgun loads were typically rated internally for ballistics in LUP, Lead Units of Pressure. Most centerfire rounds were ballistically (internal) measured using CUP or Copper Units of Pressure. It takes little imagination to know the difference in pressure. Feeding from the magazine and rimless extractors would be the least of your worries. Feeding is going to be rough on a pump or semi-auto without any modification. An extractor for a rimless cartridge break-open action is much easier.

March 26, 2002, 04:52 PM	#3
C.R.Sam Senior Member Join Date: October 29, 1999 Location: Dewey, AZ Posts: 12,858	Quite a few break top singles and doubles have been converted from shot to rifle by inserting a rifle barrel inside of the shot barrel. They come out muzzle heavy and heavy all over but it is quite doable. Recent sightings have been in .444 Marlin, .405 Winchester, 45-70. Sam

March 26, 2002, 06:25 PM	#4
James K Member In Memoriam Join Date: March 17, 1999 Posts: 24,383	Shotguns are generally designed for low pressures, in the 20,000 psi range; many modern rifle cartridges run to 60,000 and up. No matter how the measurement is done, shotguns were not designed to stand up to rifle pressures and will not do so. As Sam says, many break open shotguns have been converted to fire rifle cartridges by using liners. Companies like H&R long made single shot break open rifles on the same frame as their shotguns, but all of those have been for moderate pressure loads or were beefed up substantially. IMHO, a .416 Rem Mag in the typical .410 shotgun would be a hand grenade waiting to go boom and take some portion of the shooter's anatomy with it. Jim

March 27, 2002, 03:13 PM	#5
Mitch R Junior Member Join Date: June 13, 2001 Location: New York (no, not the city) Posts: 3	"...a .416 Rem Mag in the typical .410 shotgun would be a hand grenade waiting to go boom and take some portion of the shooter's anatomy with it." And that's without considering how much material would have to be removed from the chamber (in this case, the barrel) to get the .416 to fit. Perhaps not too much, given the thickness of a plastic shell, but still... OK, so that was a bad idea. How does pressure affect the barrel itself? Supposing I found a .41 magnum action from something else, would a rifled .410 barrel be appropriate? It'd be conveniently sized, if nothing else...

March 28, 2002, 06:27 PM	#6
James K Member In Memoriam Join Date: March 17, 1999 Posts: 24,383	Same problem. Shotgun barrels are not made of the same quality of steel as are rifle barrels and are not made to take the pressure of firing rifle ammunition. Unless this is just one of those "what if" questions, I confess I can't see what you are thinking of doing. There are plenty of reasonably priced high power rifles available without trying to make one out of a cheap shotgun. The cost of a Remington .416 would be high, but not as high as the cost of replacing a head or eyes, given that spare parts are scarce. Jim

March 29, 2002, 12:47 AM	#7
Mitch R Junior Member Join Date: June 13, 2001 Location: New York (no, not the city) Posts: 3	The question was academic-- one of those "just seemed like a good brainstorm at the time" kind of things. It's not like I have a Blackhawk and a .410 that I was actually intending to hybridize. Which, from the sound of things, is a good thing. Thank you for the advice.