Rear bag plate and their importance

Get or give advice on equipment, reloading and other technical issues.

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Norm
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Re: Rear bag plate and their importance

Post by Norm »

I think the rear plate issue needs to be cleared up a bit in the SSR's
There are so many variables in plate design that seem to push the rules.
Also every range is different so you will need a range of rear plates to match the mound conditions. One match you may be shooting on very hard gravel or rock, the next comp you will be shooting on soft dirt. At Bendigo you shoot on synthetic grass so only small 10mm spikes are allowed.

One thing that I did notice at Belmont was the number of rear plates left lying about with the spikes pointing upwards. Some of these spikes are quite sharp.
I was very careful to always have my rear plate facing downwards when waiting for my turn to go onto the mound. Its only a matter of time before someone steps onto one of these spikes and drives a 50mm spike through their foot.

Those that shoot Belmont often seem to have very good rear plates that were designed to overcome the thick grass issue.

Tilted plates with large diameter spikes or feet at the rear and the plate hollowed out in its centre? I saw a few of these at Belmont and wondered if they were within the rules? Just where is the 50mm measured from? The bottom of the plate or the step in the rear foot above the spike?
RAVEN
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Re: Rear bag plate and their importance

Post by RAVEN »

Dennis
Having been to Belmont in 2013 and suffering from those bounce verticals we were well aware of the spongy grass issue
The SA team had designed plates and special feet to cope with this issue and as far as I know they worked exceptionally well.
RB
BATattack
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Re: Rear bag plate and their importance

Post by BATattack »

Norm wrote:I think the rear plate issue needs to be cleared up a bit in the SSR's
There are so many variables in plate design that seem to push the rules.
Also every range is different so you will need a range of rear plates to match the mound conditions. One match you may be shooting on very hard gravel or rock, the next comp you will be shooting on soft dirt. At Bendigo you shoot on synthetic grass so only small 10mm spikes are allowed.

One thing that I did notice at Belmont was the number of rear plates left lying about with the spikes pointing upwards. Some of these spikes are quite sharp.
I was very careful to always have my rear plate facing downwards when waiting for my turn to go onto the mound. Its only a matter of time before someone steps onto one of these spikes and drives a 50mm spike through their foot.

Those that shoot Belmont often seem to have very good rear plates that were designed to overcome the thick grass issue.

Tilted plates with large diameter spikes or feet at the rear and the plate hollowed out in its centre? I saw a few of these at Belmont and wondered if they were within the rules? Just where is the 50mm measured from? The bottom of the plate or the step in the rear foot above the spike?



the spikes are measured from the flange to point. That was clarified by bob Pedersen.
Norm
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Re: Rear bag plate and their importance

Post by Norm »

Ok so you can design "flanged" spikes!
The spike must be no more than 50mm but the "flange" can be any length below the bottom of the plate? 8)

This would be great in levelling out the plate so that the rear bag not is sitting on a slope parallel with the mound. It would also permit better alignment of the stock with the cheek and shoulder. It could also raise the bottom of the plate above any uneven lumps in the ground that could induce rocking of the plate/bag.

Time to get to work on a new rear plate I think..
RAVEN
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Re: Rear bag plate and their importance

Post by RAVEN »

Don't forget Norm that the spikes can not be adjustable

RB :)
DenisA
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Re: Rear bag plate and their importance

Post by DenisA »

RAVEN wrote:Don't forget Norm that the spikes can not be adjustable

RB :)


Not on the mound at least.

Nothing to stop anyone from having some different types of feet or pre adjusted leg length for different mounds.

Having the plate larger than the footprint of the rear bag is a help when aligning the rear bag and cutting a handle into the back of the plate would also be a handy idea.
AlanF
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Re: Rear bag plate and their importance

Post by AlanF »

20.2.5(e) There may be no mechanical means of adjusting the [rear] bag, either laterally or vertically.


I think you will get away with simple mechanical adjustment while you are setting up. The rule above is intended to prevent adjustments between shots (i.e. using the rear rest instead of the front to do fine tuning, as is allowed in F/TR).

I have never been challenged with the Alt (1) type as sketched below. It has knurled knobs on threaded rod which can be used to change the penetration of the spikes (up tp 50mm). Its handy to have a stiff brush to clean the threads but it does the job on uneven ground well.

Another way that works well at Belmont is to use pointed angle iron on the corners as in Alt (2). I find you can press the corners in variable amounts at each corner and they stay firm, so again, good for uneven surfaces.

BTW don't expect them Crow-eaters to tell you how they do it. They're a bit tragic when it comes to team matters :D .

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williada
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Re: Rear bag plate and their importance

Post by williada »

Can’t help thinking I’m reading the “Animal Farm”, where all the animals after seeing off an abusive master made a set of laws to govern everyone’s well being. One of the laws was, “You shall not drink”. The clever politicians in the group, the pigs, moved the emphasis from law to rules then interpreted the rule or social arrangement to mean, “You shall not drink to excess”. The wanton abuse of power eventually led to their downfall because the pigs had turned into the same character as the abusive farmer when the body of the animal group realised they had been conned.

The current rule clearly says, “Means” and that means at any time. The fact that it is not policed is because few know the rules. They have become so complex. With complexity comes the race to win by technicality rather than looking at the spirit behind the letter as Alan rightly suggests. So at the moment, the adjustable plate is illegal in my view. So change the rule using our organization’s processes.

Having the discussion now is great.

The commonsense of Alan’s suggestion in “Alt 1”, would I am sure, gain the consent of the great body of shooting participants if there was a rule change so long as the front and rear bags are separated.

I would put such a move in the same category as using a joystick handle. You would rather have the rear bag set as an anchor than trying to fiddle with it during a shoot. That theoretically will form the best group, so their is no advantage in moving its position once set. There is enough to concentrate on rather than nitpicking on a technicality - its small beer.

Consult the shooters, identify the problem and take action through the proper process rather than get into argument that can damage relationships if the individual goes off on their own interpretation. David.
Tim N
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Re: Rear bag plate and their importance

Post by Tim N »

I use a rear plate made from 10mm aluminium with grip tape on top and 3 of the Farley flanged spikes attached, this allows for clearance under the plate so no rocking on the spongy mounds.
At the 1000yd range my 280AI held great elevation :D
We don't rise to the level of our expectations, we fall to the level of our training. Archilochos 680-645 BC
bartman007
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Re: Rear bag plate and their importance

Post by bartman007 »

Denis I had a discussion with a NQ team member after the shoot, and they too attributed the elevation to the spongy grass at 1000.

Now I did manage to overcome it by tilting my rear plate so that the plate did not float on a 1" lump of grass. I let the front edge push int the grass and left the back of the rest sitting just above the grass. The results speak for themselves, no vertical.

And that was using 140gn pills in a 6.5x47 doing around 2870 fps.
###
AlanF
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Re: Rear bag plate and their importance

Post by AlanF »

I think a solid base for the rear bag is more critical if you use the free recoil method. When the buttstock is firmly held and pulled into the shoulder, its downward force is met substantially by friction between butt pad and shoulder. I also think that the weight of the rear bag plays a big part - and there is no limit to what you're allowed, only a practical limit on what you can bring to the shoot and carry to the mound.
Tim N
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Re: Rear bag plate and their importance

Post by Tim N »

Hi All,
Not a great pic but you get the idea.
It passed inspection at the QLD queens but I'm thinking the wingnuts might have to go and replace them with countersunk screws so the bag is free to move.
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We don't rise to the level of our expectations, we fall to the level of our training. Archilochos 680-645 BC
AlanF
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Re: Rear bag plate and their importance

Post by AlanF »

Tim,

I agree with the countersink and flat top idea. And I find there is no need to lock the feet with another nut. Once they're pressed onto the ground they don't move, even with a sloppy thread. You need to be careful not to make the feet diameters too big - they need to be small enough to press into the surface a little. Ideally they would be slightly conical.

Alan
Brad Y
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Re: Rear bag plate and their importance

Post by Brad Y »

Tim- I like that design. Never been to Belmont and experienced the spongy mounds, but I know a few places in WA where some divots or sandy patches in a firing mound would make that worthwhile having.
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Re: Rear bag plate and their importance

Post by Tim N »

This shows the spikes from BRT
The plate is threaded so they are adjustable for height.
If I go with the countersunk option I might carry some packers of varying height for different mounds
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We don't rise to the level of our expectations, we fall to the level of our training. Archilochos 680-645 BC
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