Double Rifle: dimensions of action for bigger bores?

SHGYJ

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Hello all.

I am new here as I am also a novice to African hunting. Current experience is limited to hunting in Europe and US. Largest animal ever taken have been red stag and wild boar of ~500lbs life size each.

I am also novice to African shells and rounds. Never was a fan of bolt action and prefer to use my Drilling (Nimrod) or other break action rifles here (9,3x74R; .308Win; 7x57R; .222Rem; .22Hornet; 12ga and 20ga slugs).

Saw some double rifles in bigger bore at a local gun store and got a somewhat short answer to the question on the dimensions of the action needed for the various bigger bores. I guess the clerk smelled me not seriously interested in a purchase…

Anyway.

I would like to ask those of you who own the bigger bores, i.e. .450NE; .450/.400NE; .470NE, etc, what the three dimensions on your rifles are that I indicate with “A”, “B” and “C” on the pic below as I don’t know the correct terminology of those measuring points in English.

Very much appreciated and looking forward to your responses!

Thank you all.

J.
Break Action with dimensions copy.jpg
 
Hello all.

I am new here as I am also a novice to African hunting. Current experience is limited to hunting in Europe and US. Largest animal ever taken have been red stag and wild boar of ~500lbs life size each.

I am also novice to African shells and rounds. Never was a fan of bolt action and prefer to use my Drilling (Nimrod) or other break action rifles here (9,3x74R; .308Win; 7x57R; .222Rem; .22Hornet; 12ga and 20ga slugs).

Saw some double rifles in bigger bore at a local gun store and got a somewhat short answer to the question on the dimensions of the action needed for the various bigger bores. I guess the clerk smelled me not seriously interested in a purchase…

Anyway.

I would like to ask those of you who own the bigger bores, i.e. .450NE; .450/.400NE; .470NE, etc, what the three dimensions on your rifles are that I indicate with “A”, “B” and “C” on the pic below as I don’t know the correct terminology of those measuring points in English.

Very much appreciated and looking forward to your responses!

Thank you all.

J.

In advance and since I am not sure if your question is really serious, I am very surprised that there are big bore double rifles lying around in a local gun store.

There are very different concepts of double rifles depending on the manufacturer. Such questions should rather be asked to them. You cannot make a decision as to which rifle you will ultimately choose based on the various answers that you will receive on a Forum. If you really want to get into big game hunting in Africa, first buy or better rent a bolt action rifle caliber 375 H&H Magnum and take a look at what big game hunting in Africa is in reality. After that you can decide which rifle you want to purchase.
 
I know Heym offers five different action sizes ranging in cartridge from 300WM to 577NE. Most companies only offer three different sizes or even less. This is done to keep the cost of production down.

Best to contact Chris Sells at Heym USA for the details.
 
There are also differences for the same caliber. I noticed for example by shooting a Krieghoff DR caliber 470 Nitro Express that the action was very narrow compared to that of a DR of the same caliber from other manufacturers.
 
In advance and since I am not sure if your question is really serious, I am very surprised that there are big bore double rifles lying around in a local gun store.

There are very different concepts of double rifles depending on the manufacturer. Such questions should rather be asked to them. You cannot make a decision as to which rifle you will ultimately choose based on the various answers that you will receive on a Forum. If you really want to get into big game hunting in Africa, first buy or better rent a bolt action rifle caliber 375 H&H Magnum and take a look at what big game hunting in Africa is in reality. After that you can decide which rifle you want to purchase.
Hello grand veneur.
Thank you for your response. I am sure it is with good intentions even though I must admit that I find it interesting to welcome a newbee on the forum by questioning the seriousness of his query, and then not even answering what was asked...!
Anyway.
Thank you.
 
Well, this is what I noticed, too -and this in part the reason for my original question.
Thank you for acknowledging.
There are also differences for the same caliber. I noticed for example by shooting a Krieghoff DR caliber 470 Nitro Express that the action was very narrow compared to that of a DR of the same caliber from other manufacturers.
 
I know Heym offers five different action sizes ranging in cartridge from 300WM to 577NE. Most companies only offer three different sizes or even less. This is done to keep the cost of production down.

Best to contact Chris Sells at Heym USA for the details.
Thank you for this, BeeMa. Will try to contact him.
 
Hello grand veneur.
Thank you for your response. I am sure it is with good intentions even though I must admit that I find it interesting to welcome a newbee on the forum by questioning the seriousness of his query, and then not even answering what was asked...!
Anyway.
Thank you.

I usually don't answer questions like this without knowing who is asking them. Only the word Drilling in the first post made me do it.
 
I think the width of the receiver and the overall size would depend not only on the size of the cartridge, but the type of locking system used to keep the action closed when it is fired. The type of lever or bolt to unlock the system has a large effect on how elegant or clumsy they system can be for the user, as well as the size.
 
I usually don't answer questions like this without knowing who is asking them. Only the word Drilling in the first post made me do it.
Well then, the more I am gracious you took the effort to respond and trust you to experience the same kind of response you provided at any forum you will register in the future.

I am sure you will be as much appreciating it then as I was today.
 
Well then, the more I am gracious you took the effort to respond and trust you to experience the same kind of response you provided at any forum you will register in the future.

I am sure you will be as much appreciating it then as I was today.

It's all over, I am just active on this Forum and I don't know how much longer. Everything becomes a little strange to me as I get older. I got the advice about hunting in Africa from people who hunted there in the thirties, explains my sometimes somewhat outdated concepts regarding especially big game hunting.
 
Hello all.

I am new here as I am also a novice to African hunting. Current experience is limited to hunting in Europe and US. Largest animal ever taken have been red stag and wild boar of ~500lbs life size each.

I am also novice to African shells and rounds. Never was a fan of bolt action and prefer to use my Drilling (Nimrod) or other break action rifles here (9,3x74R; .308Win; 7x57R; .222Rem; .22Hornet; 12ga and 20ga slugs).

Saw some double rifles in bigger bore at a local gun store and got a somewhat short answer to the question on the dimensions of the action needed for the various bigger bores. I guess the clerk smelled me not seriously interested in a purchase…

Anyway.

I would like to ask those of you who own the bigger bores, i.e. .450NE; .450/.400NE; .470NE, etc, what the three dimensions on your rifles are that I indicate with “A”, “B” and “C” on the pic below as I don’t know the correct terminology of those measuring points in English.

Very much appreciated and looking forward to your responses!

Thank you all.

J.View attachment 644700

Trivia you need to know: A shotgun action is not the same as a double rifle action. In its strength. In its finish. And in its distance from the strikers to the hinge pin.

Yes, many people have built double rifles on shotgun actions, but its a clownish approach. Example: Butch Searcy used to make his large bore doubles on a Japanese made Browning 20 gauge action.

Ignoring the above facts, 20 gauge frames are most similar to 450-470-500NE barrels. This is why you'll often see "real" double rifles in those calibers offering 20 gauge barrels as an option you can add to the rifle.

The smaller actions used for some 9.3s, 375s, and even a few 450-400s can only accommodate 28 gauge shotgun barrels.

I'm unsure if any double rifle action is big enough to hold a 12 gauge shotgun barrel set. The reason for this is that the weight of even a 577NE would be excessive if it had to be wide enough to also handle a 12 bore.

TLDR: Double rifle action widths are usually similar to 20 bore shotgun widths, but they aren't the same structurally, at least in better quality ones.
 
I think that the biggest DR would be able to hold 12 gauge barrels. If you compare the barrels 600 Nitro Express, 577 Nitro Express and 16 gauge from top to bottom, there would still be room for something thicker, may be even a 12 gauge. The Webley & Scott PHV-1 action is very big, bigger that the Anson & Deeley action of the DR caliber 600 Nitro Express.

47.jpg
 
I think that the biggest DR would be able to hold 12 gauge barrels. If you compare the barrels 600 Nitro Express, 577 Nitro Express and 16 gauge from top to bottom, there would still be room for something thicker, may be even a 12 gauge. The Webley & Scott PHV-1 action is very big, bigger that the Anson & Deeley action of the DR caliber 600 Nitro Express.

View attachment 644782

You might be right, but the muzzle isn’t the right area to determine, we need to look at the breach.
 
Hello all.

I am new here as I am also a novice to African hunting. Current experience is limited to hunting in Europe and US. Largest animal ever taken have been red stag and wild boar of ~500lbs life size each.

I am also novice to African shells and rounds. Never was a fan of bolt action and prefer to use my Drilling (Nimrod) or other break action rifles here (9,3x74R; .308Win; 7x57R; .222Rem; .22Hornet; 12ga and 20ga slugs).

Saw some double rifles in bigger bore at a local gun store and got a somewhat short answer to the question on the dimensions of the action needed for the various bigger bores. I guess the clerk smelled me not seriously interested in a purchase…

Anyway.

I would like to ask those of you who own the bigger bores, i.e. .450NE; .450/.400NE; .470NE, etc, what the three dimensions on your rifles are that I indicate with “A”, “B” and “C” on the pic below as I don’t know the correct terminology of those measuring points in English.

Very much appreciated and looking forward to your responses!

Thank you all.

J.View attachment 644700
First welcome!!! No disrespect intended at all but I am curious why A, B, C are important to you in terms of dimensions? Short action versus long seen many times…your question just never seen so I am just curious why this is important to you?
 
I have owned 7 big bore DRs is why I ask
 
Trivia you need to know: A shotgun action is not the same as a double rifle action. In its strength. In its finish. And in its distance from the strikers to the hinge pin.

Yes, many people have built double rifles on shotgun actions, but its a clownish approach. Example: Butch Searcy used to make his large bore doubles on a Japanese made Browning 20 gauge action.

Ignoring the above facts, 20 gauge frames are most similar to 450-470-500NE barrels. This is why you'll often see "real" double rifles in those calibers offering 20 gauge barrels as an option you can add to the rifle.

The smaller actions used for some 9.3s, 375s, and even a few 450-400s can only accommodate 28 gauge shotgun barrels.

I'm unsure if any double rifle action is big enough to hold a 12 gauge shotgun barrel set. The reason for this is that the weight of even a 577NE would be excessive if it had to be wide enough to also handle a 12 bore.

TLDR: Double rifle action widths are usually similar to 20 bore shotgun widths, but they aren't the same structurally, at least in better quality ones.
Hi rookhawk.
Thank you for this.
Yes, this makes sense to me and explains why the actions of the doubles I saw at the shop had different dimensions but without obvious pattern re. their respective caliber.
 
First welcome!!! No disrespect intended at all but I am curious why A, B, C are important to you in terms of dimensions? Short action versus long seen many times…your question just never seen so I am just curious why this is important to you?
Hi Rare Breed.
Thank you for your kind welcome and the follow up question.
The reason for me asking for those three measures was that the doubles I had seen at said shop were most obviously different in their width but without obvious correlation to their respective caliber -which admittedly I would have guessed.
The doubles were a Heym, a Krieghoff, two Merkel, a Ziegenhahn, a Hambrusch and another one which’s manufacturer I didn’t know and don’t recall.
Calibers were 9,3x74R, .450-.400; .500-.416, .470, .500 I don’t remember for sure which double had what caliber other than the Ziegenhahn was 9,3x74R, the Krieghoff was .500-.416 and one of the two Merkel was .500NE
As rook hawk was pointing to, I guess the Merkel are based on modified shot gun actions which may explain why I for myself couldn’t detect a pattern on size of action vs. shell and caliber.
Again, thank you for following up and asking for more details.
As my curiosity prevails, what brand and caliber are your 7 big bores and in what dimension are their actions different if not the width and if at all?
 
It's all over, I am just active on this Forum and I don't know how much longer. Everything becomes a little strange to me as I get older. I got the advice about hunting in Africa from people who hunted there in the thirties, explains my sometimes somewhat outdated concepts regarding especially big game hunting.

Nice cynicism.
Not sure why you feel this sort of grim is contributing to clarify on my question, though.
Why not sharing your knowledgeability by means of providing the info I was asking for?
I didn’t ask about hunting in Africa. I asked about a simple technical detail on double rifle design that doesn’t seem obvious to me.
 
Hi Rare Breed.
Thank you for your kind welcome and the follow up question.
The reason for me asking for those three measures was that the doubles I had seen at said shop were most obviously different in their width but without obvious correlation to their respective caliber -which admittedly I would have guessed.
The doubles were a Heym, a Krieghoff, two Merkel, a Ziegenhahn, a Hambrusch and another one which’s manufacturer I didn’t know and don’t recall.
Calibers were 9,3x74R, .450-.400; .500-.416, .470, .500 I don’t remember for sure which double had what caliber other than the Ziegenhahn was 9,3x74R, the Krieghoff was .500-.416 and one of the two Merkel was .500NE
As rook hawk was pointing to, I guess the Merkel are based on modified shot gun actions which may explain why I for myself couldn’t detect a pattern on size of action vs. shell and caliber.
Again, thank you for following up and asking for more details.
As my curiosity prevails, what brand and caliber are your 7 big bores and in what dimension are their actions different if not the width and if at all?
Ah…Got it! Now I understand! Looking forward to when you hunt Africa with your chosen big bore DR!!! All of us love to read our members posted reports so we can if only for a moment live their experience!!!!
 

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