4 bore Bolt action

bigborelover

AH senior member
Joined
Jul 8, 2025
Messages
70
Reaction score
66
This may sound stupid but do you gentlemen think it is possible to make a 4 bore bolt rifle ? I think it is possible on a custom action. A 4 bore cartridge is 4.7 inches (which is shorter than 50 bmg ) the only problem i can think of other than the recoil is the width of the cartridge. What are your opinions ?
 
Ought to be one heck of a bolt face and action to employ it - all custom. The cartridge base is just over an inch in diameter.

I have held a period double. I wouldn’t want to carry it, much less fire it.

Perhaps the more reasonable question is why?
 
Last edited:
It’s a rimmed cartridge, so at that size it would be like a overblown bolt action shotgun. The Anzio 20mm is the only bolt gun that I can think of that has that large of a bolt face. There’s a Russian anti-material rifle in the same ballpark.
 
Last edited:
Ought to be one heck of a bolt face and action to employ it - all custom. The cartridge base is just over an inch in diameter.

I have held a period double. I wouldn’t want to carry it, much less fire it.

Perhaps the more reasonable question is why?
Because they don't make a 2 Bore . . . LOL
 
It’s a rimmed cartridge, so at that size it would be like a overblown bolt action shotgun. The Anzio 20mm is the only bolt gun that I can think of that has that large of a bolt face. There’s a Russian anti-material rifle in the same ballpark.

A way overblown bolt action shotgun. My Browning 12 g bolt action shotgun is designed to handle a rim with a diameter of .87 inches. A four bore would require a bolt head over an inch in diameter. Then there is the minor problem of an action large enough to handle the bolt and handle the pressure.

The Anzio could perhaps be a basis. Though its lightest configuration is around sixty pounds.
 
A way overblown bolt action shotgun. My Browning 12 g bolt action shotgun is designed to handle a rim with a diameter of .87 inches. A four bore would require a bolt head over an inch in diameter. Then there is the minor problem of an action large enough to handle the bolt and handle the pressure.

The Anzio could perhaps be a basis. Though its lightest configuration is around sixty pounds.
That goes back to your “full custom” action. Someone could probably scale up the Barrett M99 or other BMG single shot easy enough.
 
Only modern ones I know of are made on drop lock single shot actions.

Regardless of action type, I would first try to locate brass and dies before the rifle.
 
Last edited:
A Mauser M1918 Tankgewehr could make a good gateway drug for such a folly.
 
There was a Russian pump 4 bore KS-23

IMG_1679.jpeg

IMG_1676.jpeg

IMG_1677.jpeg


Civilian version.

IMG_1681.jpeg
 
Last edited:
This may sound stupid but do you gentlemen think it is possible to make a 4 bore bolt rifle ? I think it is possible on a custom action. A 4 bore cartridge is 4.7 inches (which is shorter than 50 bmg ) the only problem i can think of other than the recoil is the width of the cartridge. What are your opinions ?
I once knew a man that had a 4 bore black powder double rifle. The thing was monsterous. He had killed an elephant with it and written a magazine article about it in the 50's "True" magazine I think. His description of the recoil was frightening. Having fired an 8 bore once, I have no interest in shooting a 4 bore. The old guy gave me a 2000 grain 4 bore bullet which now sits on a shadow box in my office.

Building a new 4 bore seems like a waste of time and money to me, but hey, if you want to, I have never been accused of talking anyone out of a new gun.
 
I have one 4 Gauge Eley nitro shotgun cartridge in my collection...it makes the .600 look ordinary..

The more I look at it the less I feel the urge to fire it..
 
I think a pump action would work well. Though a 10 gauge bolt action shotgun scaled up would work better. IMHO
 
With a lathe, a milling machine and some imagination, anything is possible.

The question that's already been asked is why?

Is it possible to build a coal burning steam engine to power my pickup truck? Of curse, as there were actually steam powered cars at one time, but a gasoline or diesel are better in every way.

If you are desperate to have one, a scaled up 10ga bolt action shotgun would be the place I'd start.
 
I have one 4 Gauge Eley nitro shotgun cartridge in my collection...it makes the .600 look ordinary..

The more I look at it the less I feel the urge to fire it..

This is two 4 Bore rifle cartridges either side of a .600NE .

IMG_1701.jpeg
 
Frederick Courteney Selous used a 4-bore single shot black powder muzzleloader (a Hollis) to take over 75 elephant. He came to loathe the thing and wished he had never used it. "They kicked most frightfully, and in my case the punishment I received from these guns has affected my nerves to such an extent as to have materially influenced my shooting ever since, and I am heartily sorry I ever had anything to do with them." So much for the gentle push of black powder or not noticing recoil while actually hunting.
 

Forum statistics

Threads
64,163
Messages
1,413,230
Members
128,993
Latest member
RogerEspar
 

 

 

Latest profile posts

Beautiful Aardwolf for our Spanish client and good friend Alberto
WhatsApp Image 2025-11-12 at 17.27.22 (2).jpeg
C-YA-L8R wrote on PaulB's profile.
Hi PaulB,
I have a Ballard Arms Model 1885 chambered for .333 Jeffery Flanged. Do you have any idea where I can get ammo for this?

I am new to this forum so I am sorry if I am doing something wrong!
Thank You!
Bruce D
Lakewood Village, California

BALLARD ARMS MODEL 1885 .333 Jeffrey Single Shot Falling Block SN 1178 - (1).jpg
BALLARD ARMS MODEL 1885 .333 Jeffrey Single Shot Falling Block SN 1178 - (2).jpg
BALLARD ARMS MODEL 1885 .333 Jeffrey Single Shot Falling Block SN 1178 - (11).jpg
BALLARD ARMS MODEL 1885 .333 Jeffrey Single Shot Falling Block SN 1178 - (5).jpg
STARCHEDUPDAD wrote on Acopperdawg's profile.
what's up buddy how are you doing today
Updated available dates for 2026!

1-27 feb is open
13-31March is open
1-10 April is open
17-30 April is open
1-6 May is open
24-31 May is open
12-18 June is open
24-30 June is open
1-17 July is open
August is now fully booked
7-30 September is open
October is wide open

Get your hunt booked today!
 
Top