Understanding the regulation of double barrel rifles

[AimSmall]

Theory says, slow down the barrel time, no?

(or, just move the red dot to split the shots and enjoy shooting the rifle!)

 

[Houston Bill]

One day and everyone. My new 470 NE has 85.5 grains of RL 15 shooting 500 grain bullets. With my red dot sited in, the right barrel places my shot at 50 yards perfectly in the bulls eye. My left shot absolutely crosses over the right landing on the right side of the bullseye 2-3 inches wide. I have checked this three times. Here is my question...if I do not want my left barrel to cross at 50 yards, do I reduce my powder charge to stop this until I get my desired 2 inches of regulation or better?

Much appreciated!!!!!

@Rare Breed, if my memory servers me correct in the 3rd edition of Shooting the British Double the author says if your bullets are crossing you need to slow them down. So yes you reduce the powder charge. Did you by chance have a chronograph when you were shooting? If yes, what was the velocity? I am currently traveling so I can't check my copy of Shooting the British Double this until sometime Thursday evening.

 

[Rare Breed]

Theory says, slow down the barrel time, no?

(or, just move the red dot to split the shots and enjoy shooting the rifle!)

I am thinking to reduce the grains and experiment to see if I can stop the crossing and get a good spread.

 

[Rare Breed]

@Rare Breed, if my memory servers me correct in the 3rd edition of Shooting the British Double the author says if your bullets are crossing you need to slow them down. So yes you reduce the powder charge. Did you by chance have a chronograph when you were shooting? If yes, what was the velocity? I am currently traveling so I can't check my copy of Shooting the British Double this until sometime Thursday evening.

Thanks, I am thinking the same thing. I will experiment with reducing the powder charge and velocity. Will let everyone know my findings. Thanks everyone!!!

 

[Woodcarver]

One day and everyone. My new 470 NE has 85.5 grains of RL 15 shooting 500 grain bullets. With my red dot sited in, the right barrel places my shot at 50 yards perfectly in the bulls eye. My left shot absolutely crosses over the right landing on the right side of the bullseye 2-3 inches wide. I have checked this three times. Here is my question...if I do not want my left barrel to cross at 50 yards, do I reduce my powder charge to stop this until I get my desired 2 inches of regulation or better?

Much appreciated!!!!!

With my 9.3x74, I was needing to slow down too much to stop the crossing. Switched powders, problem solved, even though my velocity was back up almost where I started. Even better, the group was barely mixed with most shots still on their original side at 100yds (they were crossing at 75yds with the 1st powder). The powder that worked was slower than the powder that wasn't; I believe that translates to more time in the bore.

 

[KJE81]

The double rifles do have their quirks, I have actually more or less lost patience completly with mine. It works perfectly as long as you shoot both barrels within 10 seconds. But if the follow up shot comes later then 10 seconds it spreads a lot. This fall I shot a moose which fell over but then after like 30 seconds it got up again and when I shot the follow up aiming at the point just behind the front shoulder the bullet ended up hitting the moose in the neck.

It did fell again and did not rise again, but it is still somewhat annoying and apparently this is how many double rifles function, ie if the time between the first and second shot is to long it is better to reload the first barrel then using the second. So I am more and more thinking about switching to a custom built Mauser M98 instead even if this sounds like sacrilege even to myself

 

[spike.t]

The double rifles do have their quirks, I have actually more or less lost patience completly with mine. It works perfectly as long as you shoot both barrels within 10 seconds. But if the follow up shot comes later then 10 seconds it spreads a lot. This fall I shot a moose which fell over but then after like 30 seconds it got up again and when I shot the follow up aiming at the point just behind the front shoulder the bullet ended up hitting the moose in the neck.

It did fell again and did not rise again, but it is still somewhat annoying and apparently this is how many double rifles function, ie if the time between the first and second shot is to long it is better to reload the first barrel then using the second. So I am more and more thinking about switching to a custom built Mauser M98 instead even if this sounds like sacrilege even to myself

Never heard of that before....

 

[KJE81]

Never heard of that before....

Apparently the regulation is set for less then 10 seconds between shots from each barrel. If it is longer between shots the unfired barrel is in a different "place" in its recoil arc if I understood it correctly

 

[spike.t]

Apparently the regulation is set for less then 10 seconds between shots from each barrel. If it is longer between shots the unfired barrel is in a different "place" in its recoil arc if I understood it correctly

Had a few double rifles and shot a few things with them....and never experienced that issue....and shot one in build rigby years ago for the wizard who did the regulating....his tools ...a black and decker workmate bench....pieces of wood of various sizes , wire and a blow torch....was very interesting to watch him heat and lever the barrels using the wood and wire after firing one shot from each barrel ....as I said a wizard....even looked like one ..long white hair and long white beard....

 

[Rare Breed]

@Rare Breed, if my memory servers me correct in the 3rd edition of Shooting the British Double the author says if your bullets are crossing you need to slow them down. So yes you reduce the powder charge. Did you by chance have a chronograph when you were shooting? If yes, what was the velocity? I am currently traveling so I can't check my copy of Shooting the British Double this until sometime Thursday evening.

Stupid me sold my copy last year...just bought Skull Keeper's first addition though....I will not make that mistake again selling my copy!!!

 

[Woodcarver]

The double rifles do have their quirks, I have actually more or less lost patience completly with mine. It works perfectly as long as you shoot both barrels within 10 seconds. But if the follow up shot comes later then 10 seconds it spreads a lot. This fall I shot a moose which fell over but then after like 30 seconds it got up again and when I shot the follow up aiming at the point just behind the front shoulder the bullet ended up hitting the moose in the neck.

It did fell again and did not rise again, but it is still somewhat annoying and apparently this is how many double rifles function, ie if the time between the first and second shot is to long it is better to reload the first barrel then using the second. So I am more and more thinking about switching to a custom built Mauser M98 instead even if this sounds like sacrilege even to myself

Interesting, and very different than my limited experience has seen (4 different DR). It is common for me to hike to the target between shots to mark holes. Gives my barrel(s) time to cool between shots, also keeps me from getting in a hurry (and a bit of exercise). Haven't seen any difference in grouping than when I hang 2 targets, 1 for L barrel and 1 for R.