scopeing a double rifle

[reiver]

I am about to fit either a aimpoint type sight or a 1.5-4 x 20 Vrx scope on to my Beretta 689 9.3mm x74

When setting the zero up for the scope should I go for the middle of the two shot group or zero off the bottom barrel which fires first.
The rifle shoots point of aim of the bottom barrel and about 2-4" higher and 3" to the right with the top barrel at 70 yards with open sights.

Bob

 

[8x57]

It sounds like you don't yet have the load that the rifle was regulated for Bob. I get a similar result with my O/U rifle with many loads but if I can get the correct load two rounds from each barrel will fit inside a 40mm circle at 50 metres.

 

[Mr. Gain]

As 8 x 57 says.

But if you have to work with what you've got, I'd split the difference and zero so the first shot strikes 2" low and and 1.5" left of the point-of-aim. I don't know how precisely you can place a shot standing, unsupported, at a moving target -which I imagine will be the circumstances in which you plan to use this rifle -, but assuming your sights are always on the centre of the kill zone, with a mid-point zero either barrel should do the job!

 

[reiver]

Hi 8x57
I am just shooting home loads 285gr cast boolit gaschecks behind 19rs of trail boss for practice at the moment .I have room in the cases for another 2grs of tb which may help close the grouping a bit in time? .
I am saving the 285 gr RWS factory ammo for the moment rather than shooting paper with them my rifle is supposed to be regulated @ 80 meters with this ammo with 4 shots in around 4" so I am reliably informed.
I just have not had time to play on a outdoor range as yet with full power loads other than a few to have a bit of fun with.
Bob

 

[8x57]

If that's the case then Bob I would agree totally with Mr Gain and split the difference. Building a load that will match the regulated load is difficult enough without trying to do so with a cast bullet, I've been trying to do so for some time now with my 8mm O/U without any great success. If I manage to get acceptable results for a practise load with my cast bullets I find that the recoil is insufficient to reset the inertia trigger.
Welcome to the infuriating world of double rifles.

 

[VIGILAIRE]

I am about to fit either a aimpoint type sight or a 1.5-4 x 20 Vrx scope on to my Beretta 689 9.3mm x74

When setting the zero up for the scope should I go for the middle of the two shot group or zero off the bottom barrel which fires first.
The rifle shoots point of aim of the bottom barrel and about 2-4" higher and 3" to the right with the top barrel at 70 yards with open sights.

Bob

Bob - FFS man up! You know iron sights are the only way to go - btw thanks again for my present mate - Chris.

 

[reiver]

Bob - FFS man up! You know iron sights are the only way to go - btw thanks again for my present mate - Chris.

I thought you might pop up for this one chris
Just playing with my new toy & wanting to try it with a red dot to see if it makes much of
a difference? to my shooting

Bob

 

[VIGILAIRE]

Come down for a weekend and we'll have a 9.3 blastathon! Need a word anyway, will ring you tomoz.

 

[Heym SR20]

Sight it in for the first barrel - first round is the one that counts in 99% of situations. That's why you have a scope to make sure the first round goes where it is meant to.

 

[8x57]

Doesn't that depend on how you are going to use the rifle Heym? The system that I have adopted is If I am going to use my O/U for stalking (normally up to 100 yds in woodland) I have my top barrel which is closest to the scope zeroed to shoot spot on at 100 yds with light bullets. I know that I can use the bottom barrel with acceptable accurasy also at up to 50 metres but wouldn't shoot it any further than that because of divergence.
On the other hand if I were on driven boar I use a much heavier load for which the rifle is regulated and select bottom barrel first. I know that with this load four rounds, two from each barrel will shoot to point of aim at 50 M and will all fit in a 40mm circle.

At the moment I think Reiver is simply trying to set up his rifle to shoot practise loads using cast bullets so probably a compromise would be best for him. I found that fitting a scope certainly makes it easier to adjust sights when messing around with different loads but like Vigilaire I like to use the open sights.

 

[Offroad Gary]

I'd develop a load that shoots well in each barrel then get it regulated for that load.

 

[Southern]

When loading for the H&H SxS .375 I once owned, I found that shooting it offhand, resting my hand lightly on a padded rail, gave a more true and better group.

That is how they regulate the barrels at H&H and Westley Richards. They have standing rest, which is drum of about 14 inches diameter, covered in carpet. It is on an axle, so it can roll with the recoil.

 

[Mr. Gain]

Westley Richards [...] have standing rest, which is drum of about 14 inches diameter, covered in carpet. It is on an axle, so it can roll with the recoil.

That sounds like a good set-up. You don't have a photo by any chance?

I wholly agree about the need to find the right rest when zeroing. In my experience, such as it is, rifles and combination guns built on the same layout as S/S and O/U shotguns, and Drillings, have a tendency to be hold-sensitive, presumably because of the way the fore-end is clipped into the barrels, and the walnut relieved around them, which provides uneven and variable contact between the barrels and the rest.

 

[Southern]

I do have some photos, old kind, on paper. I scanned a few years ago, and need to scan more. I will try to find a good photo of the rest.

I think you need to sight in these rifles as close to how you will shoot them, offhand, because they start moving before the bullet leaves the barrel. You really need to hold all these firmly and consistently, and follow through the shot. Besides, you don't want to be shooting a .375 or .470 off the bench.

 

[VIGILAIRE]

I have had the pleasure of shooting with reiver for the last few years. We, along with others in our little group, have had our shooting focus change to doing driven shooting ' the old fashioned way' by moving to doubles.

I have seen it as an opportunity to get a double, buy ammo and just shoot. No fancy scopes, no trying to develop MOA loads, just up and at 'em confident shooting. I practice with iron sights on targets of opportunity in the backstop and instinctively know if each shot would result in a dead boar, deer or whatever.

I have a 20bore O/U very similar handling to my 9.3 and practice on rabbit clays extensively and find this prepares you well to use a double rifle on running game off hand.

Sorry if I'm rambling but just wanted to add to the thread. After speaking to reiver I'm looking forward to trying a red dot on my double and seeing where we go.

 

[Southern]

Here is a photo from the book, "Holland & Holland - Royal Gunmakers", of William Fromme, their double rifle expert, testing loads on a .470 NE from a standing rest.
View attachment 44319
And here is a page to an article by Westley Richards on how they regulate rifles to a chosen load today.
REGULATING A DOUBLE RIFLE AT WESTLEY RICHARDS | Westley Richards

 

[Mr. Gain]

Here is a photo [...] and here is [...] an article...

Perfect! Thankyou!

The rest in the Fromme photo is intriguing. It looks as though the bench top isn't fixed to the trestle underneath, but rather is able to move with the recoil of the gun, along with the rest, on a pivoting frame equipped with a spring dampener... or am I seeing it wrong!

 

[Southern]

You are seeing it right. I will find the photos of the Westley Richards tech shooting a .470 NE from the rolling rest.

I was involved in a discussion about this years ago on the Internet, and have not posted much since then, until I joined this site. One fellow did not buy it, until he built a standing rest for his .416 Remington, and could see the different in POI and groups.

Once I get any rifle sighted in close off the bags, I will do final checking an tuning the way I intend to shoot it in the field. I will shoot it offhand. I may shoot it sitting, kneeling with a sling, prone. I want to be confident in how it shoots when i plop down in that position on live game.

 

[Southern]

I have not found my photos of a .45-70 being sighted in from a standing rolling rest, in order to scan them, but I did find this one of a rest like it, with Craig Boddington firing a double rifle, to become accustomed to the sights and zero.

View attachment 44895

 

[Mr. Gain]

Thanks for that.

It looks like a useful aid for the job.

You certainly wouldn't want to use more rounds for sighting-in than you had to with a rifle like that!

Regulating them must literally be a headache.