Recoil reducers - do they work?

[PHOENIX PHIL]

I can't wrap my head around the physics of mercury reducers other than added weight. I do what most do and put a slip on limbsaver over the existing pad. It not only makes a big difference but increases the LOP by an inch which I need. A good set of steel bases and QR rings will provide added weight. The following site shows exactly how much difference changes make for comparison

http://www.handloads.com/calc/recoil.asp

It's the sloshing action in addtion to the added weight from what I understand, perhaps misunderstand. But if I understand correctly, the tube is only partially filled with liquid mercury. When firing the backward force in response to the forward moving bullet and gases is slowed by the added weight, but then as the liquid slams into the front of the tube there is further slowing of the movement of the rifle.

Best way I can think of it is to think of a 2l bottle of soda, say slightly tilted so all the soda is at the bottom while on a table top. If you suddenly move the bottle in the direction of where the bottom is, you have to move all of that mass, the bottle and it's contents. But the contents are essentially moving also towards the top of the container and as they slam into that, there's some additional resistance.

Hopefully that makes sense. Is it really worth it over a more simple solution of just adding weight? I really can't aswer that question. I just know my 8.5lb M70 in .300WM is far more pleasant to shoot than the 6.5lb Tikka T3 in the same caliber I used to have.


EDIT: Just having looked at @Shawn.54's post above this, it's kind relying on the same principle I think. The weight will push against one spring and then back in the other direction to dampen the recoil. The idea is there's additional weight, but it is kind of "floating" not being firmly in position with respect to the rest of the system.

 

[Shawn.54]

I forgot to add that recoil was reduced but how much due to movement of weight or just more weight I can't say.
For all I know it could be just a fancy way to hold weight in a hollow stock.
I started with a 6.9# rifle now with weight and scope it's just under 9#
Shawn

 

[GA Hunter]

Guess I should have been a little clearer. I try to shoot at least 5-10 rounds of 375 off sticks, 5-10 of 30-06 or 300 WM off sticks, and 20-30 rimfire (17HMR, 22LR, or 22WM) off sticks each session. Occasionally hard ball 223. Just trying to learn to shoot off sticks. Still not very good as in 6" groups at 100m (375 better, 22LR worse). Hopefully by my next hunt in September I'll improve.
I do a lot of experimenting (illness I'm plagued with) of loads and that requires benching a gun. I have between 300-400 rounds through my 375 since I got it a few months ago.
I drive 1 1/2 hours to a range to shoot, so I pretty much spend the day.
Hope this sounds better?

@Ridgewalker

Given the number of rounds you have fired from the sticks you may have already figured this out. When I first started shooting from sticks I struggled with getting the gun to settle down and realized that it was because my right elbow, shooting right handed, was unsupported. I now refer to it as the "chicken wing effect". Once this occurred to me I tucked it in tight to my side and voila'. It settled things considerably. I have even had a PH step in as I was getting on the sticks and offer his shoulder as support for my elbow. Both techniques work well for me.

Good luck and I'm also glad to see that you've realized that even a rimfire can be used to work on this skill.

Happy hunting!

BD

 

[Nyati]

Three months ago we ran a test for Armas Internacional magazine, with two rifles in 416RM.

One was a normal Sako 75, the other a Mauser 03 Africa with a Kickstop recoil reducer and Magnaported barrel. This combination should have reduced total recoil by at least 50%.

We did not have a scientific way to measure recoil, except with a videotape showing muzzle rise, and our own (2 shooters) perception.

Our estimation... around 15/20%

Disclaimer, I am not the actor !

 

[lcq]

It's the sloshing action in addtion to the added weight from what I understand, perhaps misunderstand. But if I understand correctly, the tube is only partially filled with liquid mercury. When firing the backward force in response to the forward moving bullet and gases is slowed by the added weight, but then as the liquid slams into the front of the tube there is further slowing of the movement of the rifle.

Best way I can think of it is to think of a 2l bottle of soda, say slightly tilted so all the soda is at the bottom while on a table top. If you suddenly move the bottle in the direction of where the bottom is, you have to move all of that mass, the bottle and it's contents. But the contents are essentially moving also towards the top of the container and as they slam into that, there's some additional resistance.

Hopefully that makes sense. Is it really worth it over a more simple solution of just adding weight? I really can't aswer that question. I just know my 8.5lb M70 in .300WM is far more pleasant to shoot than the 6.5lb Tikka T3 in the same caliber I used to have.


EDIT: Just having looked at @Shawn.54's post above this, it's kind relying on the same principle I think. The weight will push against one spring and then back in the other direction to dampen the recoil. The idea is there's additional weight, but it is kind of "floating" not being firmly in position with respect to the rest of the system.

a T3 in 300, brutal. I have a T3 laminate in 300wsm weighted down with a heavy scope, steel rings and bases and a slip on recoil pad and it still isn't pleasant to shoot

 

[colorado]

I have them in my 500 Jeffery. It was too muzzle heavy for me and it the mercury recoil reducer(s) got the balance point to the middle of the floor plate which is where I wanted it. With scope and rings my 500 Jeffery weighs 12 lbs unloaded, which for me is about perfect. Because of the balance point it feels light and lively in my hands, not so much at 11500 feet elevation elk hunting

 

[ArmyGrunt]

It's the sloshing action in addtion to the added weight from what I understand, perhaps misunderstand. But if I understand correctly, the tube is only partially filled with liquid mercury. When firing the backward force in response to the forward moving bullet and gases is slowed by the added weight, but then as the liquid slams into the front of the tube there is further slowing of the movement of the rifle.

Best way I can think of it is to think of a 2l bottle of soda, say slightly tilted so all the soda is at the bottom while on a table top. If you suddenly move the bottle in the direction of where the bottom is, you have to move all of that mass, the bottle and it's contents. But the contents are essentially moving also towards the top of the container and as they slam into that, there's some additional resistance.

Hopefully that makes sense. Is it really worth it over a more simple solution of just adding weight? I really can't aswer that question. I just know my 8.5lb M70 in .300WM is far more pleasant to shoot than the 6.5lb Tikka T3 in the same caliber I used to have.


EDIT: Just having looked at @Shawn.54's post above this, it's kind relying on the same principle I think. The weight will push against one spring and then back in the other direction to dampen the recoil. The idea is there's additional weight, but it is kind of "floating" not being firmly in position with respect to the rest of the system.

Pretty good explanation. Another part of this equation (I'm no physicist) is the friction and momentum.
Mercury is a heavy metal. Objects at rest tend to stay at rest. So the energy of recoil wanting to move everything essentially has to put more effort into moving the heavy, slow and lazy liquid mercury. The time it takes to accelerate mercury slows down the impulse felt at the shoulder.
Other types of reducers use spring sets for the same reason: slowing the rearward movement of the energy.

Alternatively, you may have seen kung fu demos where the guy will slap the ground. That energy transfer from hand to ground reduces what is absorbed by the body falling into a hard surface. I've tried this one, and there's a real difference between falling flat and adding the slap.

I do, however, agree with a previous post about recoil feeling different being off the bench. My 375 River is much more kind to me, and fun, shooting free hand. And more so when I hit that tannerite!!

 

[ArmyGrunt]

Three months ago we ran a test for Armas Internacional magazine, with two rifles in 416RM.

One was a normal Sako 75, the other a Mauser 03 Africa with a Kickstop recoil reducer and Magnaported barrel. This combination should have reduced total recoil by at least 50%.

We did not have a scientific way to measure recoil, except with a videotape showing muzzle rise, and our own (2 shooters) perception.

Our estimation... around 15/20%

Disclaimer, I am not the actor !

looks like the Sako was softer shooting with less muzzle rise. I didn't expect that, based on what I've read of magna porting. Did it seem like having that done would be worthwhile?

 

[Shootist43]

ArmyGrunt, please clarify your previous comment "Did it seem like having it done would be worthwhile?"

 

[johnnyblues]

I actually called the airline (United in this case) to confirm what I suspected (laid out in the linked thread)..

There is zero problem traveling with a mercury recoil reducer from the US to Africa.

No TSA reg against it. No FAA reg against it. No airline policy against it.


Now, whether or not United will try to bump me off the flight and beat me for refusing to leave... thats a different story...

Pray they do...You will get a hefty paycheck!

 

[ArmyGrunt]

ArmyGrunt, please clarify your previous comment "Did it seem like having it done would be worthwhile?"

Did the effects felt from shooting the Magna ported gun give the impression that it was a worthwhile investment? I've looked all over the web to find useful first hand opinion on the system, but haven't found one yet

 

[bilmcc]

I have not magna-ported a rifle, but I did Magna-port a Ruger 480 revolver. It helped greatly in managing the 400gr bullets. Well worth the cost, for what this is worth.

 

[Nyati]

Did the effects felt from shooting the Magna ported gun give the impression that it was a worthwhile investment? I've looked all over the web to find useful first hand opinion on the system, but haven't found one yet

It helps, but certainly not as advertised, not a 25% reduction by itself.

 

[colorado]

I don't think the mercury recoil reducers actually reduce the amount recoil, except for the amount of weight they add. The inertia of the mercury is intended to slow the velocity of the recoil. It seems to work, I can't quantify it though.

 

[ve7poi]

I put a mercury tube in my Sako 500 j but for balance after getting stock to my longer pull made rifle balance nicely as for recoil I seem to be able to get second round off a tad quicker.
I equate this to a slight reduction to recoil and muzzle flip.

 

[Rule 303]

Mercury will dissolve the alloy of an aircraft fairly quickly. I have seen the damage done by a thermometer that broke on board a 737. Plane was out of commission for months. As one rib and several longrons were totaled.

I would suspect that it would take a major malfunction for the mercury in a recoil reducer to escape. Can not comment on the US but it is illegal to take mercury onto an aircraft in Australia without a dangerous goods permit for the flight. The chances of the recoil reducer being picked up, use to be almost zero, how ever with more and more baggage being X-Rayed the chances of discovery are increasing.

 

[Rule 303]

I actually called the airline (United in this case) to confirm what I suspected (laid out in the linked thread)..

There is zero problem traveling with a mercury recoil reducer from the US to Africa.

No TSA reg against it. No FAA reg against it. No airline policy against it.


Now, whether or not United will try to bump me off the flight and beat me for refusing to leave... thats a different story...

mdwest not to disagree with you or teaching you to suck eggs, but to be safe check what they do allow. If the legislation bans dangerous goods ( or similar terminology) it may list what Dangerous goods are. If mercury is listed as a dangerous/hazardous or similar then it most likely won't list items as recoil reducer. Also in our legislation, you have to cross check 2 or 3 acts and not only see what they do list but also what they don't list. That is they may list the items that are allowable and anything they do not list is prohibited without permission. from memory QANTAS has a thermometer outline on its dangerous goods brochure. thing is now days most thermometers don't contain Mercury.

Also need to check the receiving country's regs. As under the various conventions that countries may of signed up to, the receiving country might be obliged to act regardless of what the rules are in the host country.

I am no solicitor but have read the regs and acts here. not as straight forward as I would think or like.

 

[mdwest]

mdwest not to disagree with you or teaching you to suck eggs, but to be safe check what they do allow. If the legislation bans dangerous goods ( or similar terminology) it may list what Dangerous goods are. If mercury is listed as a dangerous/hazardous or similar then it most likely won't list items as recoil reducer. Also in our legislation, you have to cross check 2 or 3 acts and not only see what they do list but also what they don't list. That is they may list the items that are allowable and anything they do not list is prohibited without permission. from memory QANTAS has a thermometer outline on its dangerous goods brochure. thing is now days most thermometers don't contain Mercury.

Also need to check the receiving country's regs. As under the various conventions that countries may of signed up to, the receiving country might be obliged to act regardless of what the rules are in the host country.

I am no solicitor but have read the regs and acts here. not as straight forward as I would think or like.

youve already made this case in the thread that is linked on the first page, and your assessment has been confirmed to be incorrect. What may apply in Australia clearly does not apply in the vast majority of countries in the rest of the world.

There is no federal regulation, no state law, and no airline policy in the US that prohibits mercury recoil reducers on aircraft. There is no law and there is no airline policy in South Africa or with South African Airways that prohibits mercury recoil reducers on aircraft. There is no law and there is no airline policy in Germany or with Lufthansa that prohibits mercury recoil reducers on aircraft.

There are numerous people on this board that have stated they have traveled with mercury recoil reducers internationally numerous times using a wide variety of paths, without ever having trouble with their carriers, the airports, security, etc.

Mercury Recoil Reducers are consumer sporting good products, not commercial products, that contain small quantities by FAA and TSA definition, and therefore not regulated.

The law has been reviewed, the airlines have been called, the facts are documented (in this thread, the linked thread, and others).

Quantas may have a thermometer listed as a dangerous good, but the US Federal government actually specifically states that a mercury thermometer is OK in checked bags as long as it is in an protective thermometer case (a $1.00 item made of thin plastic that you can buy in any pharmacy in the US) in Title 49, Subtitle B, Chapter 1, Subchapter C, Part 175, Subpart A, Part 175 (US Federal Law regarding Transportation and Carriage by Aircraft).

If/when traveling from the US to Australia for swamp buffalo, Australian Civil Aviation Amendments to Regulations 8 and 365 that were made in 2003 might be of concern (that is when/where Australian law was amended to include a mercury thermometer on the dangerous goods list).

Traveling from the US to Africa however, on any reasonable route imaginable however it is not a concern as long as you avoid Air France (transiting France is ok. Its the airline policy that is the problem, not the law).

For what it is worth, UK Civil Aviation regulations allow mercury thermometers under the same conditions as the US FAA, German Aviation Authority allows them, French law allows them as well (although Air France prohibits thermometers on its aircraft). New Zealand Civil Aviation and Air New Zealand specifically say that mercury thermometers for personal use are ok (just gotta have the protective case.. same thing as the US),, Maybe New Zealand is the better choice for a Water Buffalo hunt instead of the Aussie Swampie!

I did find two other airlines (not federal law) that prohibit mercury thermometers.. Singapore Air and Gulf Air.. I am sure there are others..

But clearly the vast majority of airlines and countries see zero problem with this.

 

[mdwest]

I don't think the mercury recoil reducers actually reduce the amount recoil, except for the amount of weight they add. The inertia of the mercury is intended to slow the velocity of the recoil. It seems to work, I can't quantify it though.

I think youre right on this, although I cant prove it.

I think I'd get the same effect if I added 16oz of lead to the stock in terms of actual recoil reduction.

 

[colorado]

As far as mercury goes there is some in all computers. Are we not flying with computers anymore?