Recoil shock absorbers, legal?

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Tim N
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Location: Branxton NSW

Recoil shock absorbers, legal?

#1 Postby Tim N » Wed Jun 24, 2015 9:17 pm

Hi All,
One for the bush lawyers
I'm interested in a shock absorbing system for an f open rifle.
Brownells stock one and I wanted to know if they are ok for comp use?
Would someone like to comment on their effectiveness
We don't rise to the level of our expectations, we fall to the level of our training. Archilochos 680-645 BC

Brad Y
Posts: 2017
Joined: Fri Jun 26, 2009 8:21 pm

Re: Recoil shock absorbers, legal?

#2 Postby Brad Y » Wed Jun 24, 2015 9:42 pm

Not sure if they are legal- assuming they are, but do they really work as good as adding the same amount of weight?

Norm
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Location: Gippsland, Victoria

Re: Recoil shock absorbers, legal?

#3 Postby Norm » Thu Jun 25, 2015 9:24 am

I have believe mercury reducers are ok. Not sure about other systems.

BATattack
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Joined: Mon Dec 29, 2008 10:29 pm

Re: Recoil shock absorbers, legal?

#4 Postby BATattack » Thu Jun 25, 2015 10:50 am

Why wouldn't they be legal? as long at its include in the overall weight I don't see any reason why not?

RDavies
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Location: Singleton NSW

Re: Recoil shock absorbers, legal?

#5 Postby RDavies » Thu Jun 25, 2015 1:06 pm

BATattack wrote:Why wouldn't they be legal? as long at its include in the overall weight I don't see any reason why not?

There was some concern that the various spring loaded butt plates might be considered to be a return to battery device but it seems common sense has prevailed so far and a few F/TR shooters over seas have been using these butt plates openly with no problems.

DenisA
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Location: Sunshine Coast, QLD

Re: Recoil shock absorbers, legal?

#6 Postby DenisA » Thu Jun 25, 2015 1:24 pm

I had thought of the idea of the butt plate being attached via a small coil over strut inserted mostly into the stock. The strut proportioning something to the effect of 20/80. That way it would compress easily and would rebound very slowly. That would stop it from being considered "return to battery". I had toyed with that idea years ago when I started shooting 230gn Hybrids from my 300wsm at a reasonable speed. I dropped the idea when I installed an X-coil recoil pad. It made the rifle an absolute pleasure to shoot. Couldn't feel anything.

Tim N
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Joined: Fri Jan 25, 2013 8:18 pm
Location: Branxton NSW

Re: Recoil shock absorbers, legal?

#7 Postby Tim N » Thu Jun 25, 2015 3:17 pm

Hope this works, an example of how recoil can effect your life :D
http://www.youtube.com/watch?v=CIlQJoelCXk
We don't rise to the level of our expectations, we fall to the level of our training. Archilochos 680-645 BC

williada
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Joined: Wed Jul 22, 2009 12:37 am

Re: Recoil shock absorbers, legal?

#8 Postby williada » Thu Jun 25, 2015 4:50 pm

Tim, you really have to think hard about what you want a recoil reducer to do for you. Is it the reduction of felt recoil to handle that magnum or do you think it will aid accuracy and bag handling? It is not a return to battery rest because you still have to re-position the stock manually.

Some would argue that the recoil reducer is no different to adding extra weight to a stock because the inertia or stock momentum depends on mass X velocity. So if you are not changing the velocity, but alter the mass, the stock will be harder to move as it is stationary when fired. I would think in these terms, it is critical no matter what the mass of your gear is, that its balance point for bag handling is more important. Think about that when you fit one, you might have to add more weight forward.

Recoil reducers that are uncoupled weights, like lead weight suspended in oil with springs either end or a mercury filled reducer probably do not reduce recoil much more than the fixed weight. Yes, they have a longer dwell time before things move because they are uncoupled but how significant that is depends on the pendulum effect or more specifically the length of travel made - the longer the length on a weak spring, the greater the dwell time. But will this improve accuracy? Elvis has left the building with such a small rearward movement of the barrel. You are for practical purposes dealing with the following crowd spilling out of the building and how to handle them if they are a bit rough.

However, the shape of your stock, or whether you have a cheek piece can interfere with the position and more importantly the length of mechanism you can fit. Go for the longest one you can get. Of course mercury ones are heavier and therefore you don’t need the length. But without length you get a shorter dwell time. Catch 22. Not quite, because the weight is more significant than dwell time.

If a recoil reducer is very full with mercury, it acts more like a fixed weight. The size of the holes in a recoil reducer that allow the mercury to flow and uncouple also influence its effectiveness. Of course the lead ones or tungsten ones may have greater ability to alter spring pressure to adjust the mechanism to suit the calibre you are shooting depending on the brand.

The other benefit of the sliding metal mechanisms is that some have counter rifling like engraving to dampen sideways torque as the mechanism slides back in the oil bath.

While mercury and lead do absorb vibrations, I think a mercury damper around the barrel would have more effect on harmonics than can be attributed to it in the rear of a stock. Its sure not an argument for mercury in that regard.

The recoil reducer has more attributed to it for harmonics than is warranted. The harmonic patterns find their source in muzzle jump. The muzzle jump finds its source on the pivot point or fulcrum point of your shoulder or resistance of the rear bag if shooting free recoil. The amount of jump you get then is determined by the centre of gravity of the rifle in relation to the bore line. Of course the recoil reducer will act in this situation like any weight determining the centre of gravity of the rifle in relation to the bore line. Some of these recoil reducers are attached to an adjustable butt plate which effectively alters the pivot point which has more influence on barrel jump. That’s the type I would use. Of course the closer the bore line is to the centre of gravity of the rifle the more rear thrust you have. So just maybe for the big magnums, a lower butt will give more pain relief. Stock design is most important, and really calibre dependant for the right balance. David.

williada
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Re: Recoil shock absorbers, legal?

#9 Postby williada » Thu Jun 25, 2015 5:27 pm

Now Danny, mercury in your barrel tuner just might be something. :D

Tim N
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Location: Branxton NSW

Re: Recoil shock absorbers, legal?

#10 Postby Tim N » Thu Jun 25, 2015 6:39 pm

My thoughts of a recoil reduced were more to aid in accuracy by allowing the rifle to move more freely as the bullet leaves the barrel with the added bonus of less recoil
We don't rise to the level of our expectations, we fall to the level of our training. Archilochos 680-645 BC

DannyS
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Re: Recoil shock absorbers, legal?

#11 Postby DannyS » Fri Jun 26, 2015 4:09 pm

Haha David, hadn't considered that :idea:

Cheers
Danny


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