I have a Browning Continental which I purchased new in 1983. The set which has .30-06 over and under barrels. In 1991 I had a set of claw mounts installed and an under barrel swievel stud (silver soldered) and yes the regulation changed. First it was very accurate with 150 grain bullets, and now it shoots 200 grain bullets the best, but not as well as the 150's used to do. I sometimes joke that I would have paid extra if I had known I would get these results, but I miss the guilded accuracy of the former setup. Accuracy was 1.5 MOA and is now 4 MOA at 100 yards. Any ideas????????/

Is it shooting off face?

You can send it to a double gunsmith, such as Champlin's in Oklahoma to find out.

500, I don't know what the term "off face" means... Actuaally the lower barrel shoots higher, and the upper barrel shots lower with a very slight left and right diference, about 3/4 inch.

I believe your rifle can be re-regulated for the load of your choice. I would contact New England Custom Guns about this. They made a set of claw-mount rings for an old J.P. Sauer double I have. They did a good job, and re-regulation was not necessary. It shoots into about 2", R&L barrels, with a 200-grain Nosler. (8X60RS). A strange thing, though. It will not shoot the 200 grain Speer spitzer at all well, using the exact same powder charge and bullet seating depth as with the Nosler PJ.

[ 04-22-2003, 19:38: Message edited by: eldeguello ]

308Sako,
Mounting a scope often de-regulates a double, as the vibration pattern of the barrels is affected by the added mass. Now, your rifle crossfires, which is a sign of too short barrel time. To increase barrel time : increase bullet weight (as you have already done and proven to yourself) or lower velocity of the lighter bullet. BTW, shooting with the scope on/off will affect barrels grouping.

308Sako:

I'm curious, how does the rifle shoot now without the scope attached? Are the groups bigger with the scope only?

Andre is quite right. Getting bigger groups with a double rifle after adding a scope is fairly common, although some tolerate it with no problem at all. I haven't handled one of the Brownings in years but, as I recall, they were fairly lightweight and the barrels had a rather slim profile. Given such slim barrels, I suppose harmonics could have something to do with it. However, what usually plays hell with the regulation is the change in weight with the concomitant change in recoil arc.

"Regulating" a double rifle is simply the process of adjusting the barrels for the difference in their movement under recoil during "barrel time" (the period that the bullet is still in the barrels while they are moving in recoil) for the chosen load. Once this is set, decreasing barrel time (by using a lighter bullet at higher velocity for example) will usually result is crossfiring, because the barrels don't move as far in recoil before the bullet leaves the muzzle.

Generally, adding weight will have the same effect. If your rifle is as light as I remember the Brownings being, the addition of a scope and mounts would represent a significant percentage increase in weight. The additional weight, especially when added over the barrels, dampens recoil, changing the recoil arc during barrel time - they don't move as fast or as far. Stepping up to 200 grain ammo increases both recoil and barrel time thus partially reversing the effect of the added weight, which is why it shoots better with 200s now.

What kind of scope did you mount and, more importantly, what does it weigh? If a more compact, lighter weight scope is available, I would try that first. If that doesn't work, you're probably stuck with re-regulating.

J. J. Perodeau in Enid, Oklahoma re-regulated one of mine and did a superb job. I believe he is currently getting around $600 for this service. His number is (580) 237-7388.

Best of luck with it.
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"Serious rifles have two barrels, everything else just burns gunpowder."

Gentlemen, thank you for your most informative answers. I have been playing with loads, and really didn't try to see the effect without the scope which is a 1.5 x 5 Leupold, heavy crosshair. I will most definately try to slow down the barrel time somewhat more, and also group the rifle without the scope. This is going to be fun, so thanks once again.

308Sako:

Just a thought. If the barrels have enough pitch to stabilize them, handloaded 220s or 250s might regulate perfectly, duplicating the performance of the .318 Westley Richards but with bullets of higher sectional density. That wouldn't be a bad place to be.
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"Serious rifles have two barrels, everything else just burns gunpowder."

400 NE, you must be reading my mind. I have some old Barnes original 250's and some Norma 220's which shall see the dark of the bore shortly. Will keep you posted. Once again many thanks

308, let us know your results. This is very useful information!!

Will do re: results... a most interesting pursuit in the off season.