Mercury recoil reducer

[long40shot]

I've got a 300wm hunting rifle that's in a HS Precision sporter stock. Is it possible to install a mercury recoil reducer in the butt stock? I know there is a hollow cavity in there.

Thanks
Matt

 

[BenPerfected]

Use one in a Sporting Clays gun. It adds weight but not sure the mercury adds much to help manage the recoil. IMO, the additional weight is more helpful in balancing the gun to smooth the swing.

Here is some more info:

V. Mercury and Mechanical Recoil Reducers

These cylindrical devices are usually implanted in the butt stock of a shotgun, inserted into the empty chamber of a double, or screwed onto the end of the magazine tube of a repeater. Theoretically, they use mercury or a moveable mechanical weight that is supposed to attenuate felt recoil by spreading it out over a longer period of time. The claim is that the mercury (or mechanical weight) moves forward in the tube as the gun moves backward in recoil, thus "borrowing" some of the recoil energy and lowering the maximum amplitude of the kick. The weight returns to its start position, redepositing the borrowed energy, after the stock stops moving backward.

According to my shoulder, these devices seem to reduce recoil no more than adding weight in any other manner. (Adding weight, of course, does reduce recoil.) Dead Mules don't kick, perhaps, but they can nibble at your wallet. The mercury recoil reducers do add a humorous gurgling sound not available in stock factory shotguns. If mounted in the buttstock they also move the gun's point of balance back. This may be fine if the gun started out muzzle heavy, as many pumps and autos do, but is not so hot if the stock gun balanced properly.

 

[watercam]

I installed one in the forearm of a Kimber 325WSM and found it did reduce recoil somewhat. As long as you can fill in around the tube of the reducer so that it is held solidly in place it should be functional. Perhaps filling the void with expanding foam and then gluing the reducer in place?
Your recoil pad is probably glued on so there is your first challenge...

 

[dickn52]

Use one in a Sporting Clays gun. It adds weight but not sure the mercury adds much to help manage the recoil. IMO, the additional weight is more helpful in balancing the gun to smooth the swing.

Here is some more info:

V. Mercury and Mechanical Recoil Reducers

These cylindrical devices are usually implanted in the butt stock of a shotgun, inserted into the empty chamber of a double, or screwed onto the end of the magazine tube of a repeater. Theoretically, they use mercury or a moveable mechanical weight that is supposed to attenuate felt recoil by spreading it out over a longer period of time. The claim is that the mercury (or mechanical weight) moves forward in the tube as the gun moves backward in recoil, thus "borrowing" some of the recoil energy and lowering the maximum amplitude of the kick. The weight returns to its start position, redepositing the borrowed energy, after the stock stops moving backward.

According to my shoulder, these devices seem to reduce recoil no more than adding weight in any other manner. (Adding weight, of course, does reduce recoil.) Dead Mules don't kick, perhaps, but they can nibble at your wallet. The mercury recoil reducers do add a humorous gurgling sound not available in stock factory shotguns. If mounted in the buttstock they also move the gun's point of balance back. This may be fine if the gun started out muzzle heavy, as many pumps and autos do, but is not so hot if the stock gun balanced properly.

Used one on a Beretta for awhile. Like you not sure it ever helped all that much. Mike at PMS had others he liked more for sporting shotguns though.

 

[deepwater]

Besides the concentrated added weight of the unit, the sloshing back then forward of the mercury does reduce felt recoil.

Your stock should have foam inside. This can be drilled the the reducer inserted with epoxy under the recoil pad parallel to the bore. Have this setup on a .375 Ruger and it works.

As stated elsewhere, a custom unit was placed in a 12 ga. pump for a bounty hunter and used successfully.

 

[riverwolf1]

If your looking to tame recoil, why not have a gunsmith install a muzzle brake! This would reduce recoil without adding a bunch of weight, probably more effective too!

 

[JRS]

I've got a 300wm hunting rifle that's in a HS Precision sporter stock. Is it possible to install a mercury recoil reducer in the butt stock? I know there is a hollow cavity in there.

Thanks
Matt

Be sure your stock fits you well, and add a quality recoil pad to the mix. A mercury recoil reducer is simply adding weight to the gun. You can achieve the same result by adding lead tennis racket tape to your gun, for less money. The way the stock fits you is of utmost importance.

 

[hogpatrol]

All of my H.S. stocks have the butt pad glued on. When I asked their service department about installing a recoil reducer, I was told I'd have to saw off the pad. Went with brakes on those stocks.

 

[M-61]

Shot trap for a time with an O/U 12 ga. Put the mercury reducer in the top barrel. What the scientific reduction was I have no idea. It just 'felt' like less recoil to me and that's all that I am concerned with.

 

[hogpatrol]

I've got a 300wm hunting rifle that's in a HS Precision sporter stock. Is it possible to install a mercury recoil reducer in the butt stock? I know there is a hollow cavity in there.

Thanks
Matt

PM sent. I have a B&C 700 LA BDL with one factory installed I can let go.

 

[deepwater]

If your looking to tame recoil, why not have a gunsmith install a muzzle brake! This would reduce recoil without adding a bunch of weight, probably more effective too!

I whole-heartedly (sic) agree with this despite my previous post. The noise and blast is the trade off.

 

[savagedasher]

If your looking to tame recoil, why not have a gunsmith install a muzzle brake! This would reduce recoil without adding a bunch of weight, probably more effective too!

I have both in fact two mercury reducers in one gun plus a brake . Larry

 

[DRNewcomb]

Not sure what mercury does that a similar weight of lead wouldn't also do.

 

[spclark]

Not sure what mercury does that a similar weight of lead wouldn't also do.

Mercury, being a liquid at normal temperature, will move in its container where solid Lead won't.

For an equal volume you might be right; where the greater density of Mercury (13.56 grams /cu. centimeter) compared to lead (a solid, at 11.34 g/cm3) would suggest a smaller cavity, any container for it with sufficient space to allow movement would require a bigger cavity.

 

[dickn52]

Not sure what mercury does that a similar weight of lead wouldn't also do.

Think of it as a car shock absorber instead of a solid extra weight on the gun. The mercury will shift and absorb recoil as it travels to the rear. Lead would just sit there and travel with the gun at the same speed. No dampening at all on the lead.

 

[DRNewcomb]

Mercury, being a liquid at normal temperature, will move in its container where solid Lead won't.

For an equal volume you might be right; where the greater density of Mercury (13.56 grams /cu. centimeter) compared to lead (a solid, at 11.34 g/cm3) would suggest a smaller cavity, any container for it with sufficient space to allow movement would require a bigger cavity.

What I don't get is how moving is an advantage. The gun recoils, the mercury stands still until it hits the end of its container, when some of the momentum is transferred to the mercury. This is similar to Newton's cradle. The problem is that by the time this happens the kick has already been transferred to the shooter's shoulder. It's easy to see how adding a slug of lead to the butt-stock reduces felt recoil: It reduces the rearward velocity of the gun, spreading the recoil out over a longer period. I can understand how some gas actions (e.g. Garand) reduce recoil by kicking a lot of mass in a rearward direction.

Mercury to me sounds more like a blow-back action where the momentum is mostly in the slide until it hits the frame then transfers all its momentum to the frame and hand at once. Again, like Newton's cradle.

What I'm getting at is that no one has ever shown me the math for how it works. It's all just arm waving and mumbo-jumbo.

 

[DRNewcomb]

Think of it as a car shock absorber instead of a solid extra weight on the gun. The mercury will shift and absorb recoil as it travels to the rear. Lead would just sit there and travel with the gun at the same speed. No dampening at all on the lead.

So, if it works so well, why not just put some cans of mercury on car axles? Well, it's a completely different problem. A shock absorber works by compressing quickly and expanding slowly. It burns up energy in hydraulic action. It dampens harmonic resonance of the axle & spring system. The wheels essentially skip over the last half of the bump. I seem to recall some guns that actually had a shock absorber incorporated into the butt-stock, so that the butt-plate traveled in an inch or so. I don't know how well that worked.

P.S. Here's an article on recoil reducers. Here's my take-away from the article: "As a practical matter, subjectively most shooters I know can’t tell the difference in recoil between an 8 ounce spring loaded weight and an 8 oz fixed weight. Of course, there is the occasional princess who can detect that pea, but most can’t. I sure can’t."

 

[Kenneth66]

For what it's worth , good recoil pad worked for me , Kenneth


http://www.chuckhawks.com/shotgun_recoil.htm

 

[swd]

I've owned, shot and worked on a lot big rifles up to .600" and shot hundreds of thousands of shotgun rounds competetively. I've used mercury reducers, weight by itself and muzzle brakes. Mercury reducers work, but probably 90% of the reduction comes from weight. You can feel the mercury moving and for some people the mercury sloshing around is an issue too.

A really good pad is your first line of defense!! If it's hard with sharp corners it will always poke you in an unpleasant way.

From there a brake is more effective, but of course with the side effect of muzzle blast and noise. Weight is can be very effective depending on how much you can stand. 2 lbs is far more effective that 8 oz...

So for the whole package you need to consider all of the above.

 

[spclark]

At the end, this game is about physics after all.

Sir Isaac figured it out centuries ago, nothing's changed much since. Bigger bullets, higher velocities, heavier rifles... if they're not gonna be mounted on a carriage, with wheels.

Why there are weight limits on some classes of rifles built for competition, and muzzle brakes (for those who don't like having people standing too close next to them).