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hoser
03-24-2008, 02:25 PM
Here are the air rifle benchrest rules (minus the springer rules, which are very clear):

CLASSES

A. Unlimited
Unlimited scope power. Muzzle velocity greater than 600 fps. Gun must be designed to be shoulder fired or for pistols, hand held.

B. Match
Same rules as unlimited class. Muzzle energy 7 ftpounds or less. (7 FPE)

2-part question:

1. Can a fellow use the same gun for Unlimited and Match if the gun either conforms to each class or is/can be changed to conform?

2. Does the Match gun "have to" exceed 600 fps, but be under 7 FPE? The "Same rules as Unlimited" indicates that would be true. (Maybe not possible!)

I think I get what is going on with the rules, but someday it could be a matter of contention.

HosÚR

Fred J
03-24-2008, 04:27 PM
My CO2 rifle chronographs at 592 fps, +/- 1 pfs. How many FPE is that?

DonMatzeder
03-24-2008, 04:28 PM
I "think" the intent was to make any gun eligible to shoot in the unlimited class but the low powered guns would be at a disadvantage. The match guns were power restricted to keep a level playing field for people that had match guns and wanted to compete with them. The inclution of a need for an unlimited gun to shoot in excess of 600 fps is a mistake and , again I "think", should be edited out of the rules this next year.

DonMatzeder
03-24-2008, 04:28 PM
My CO2 rifle chronographs at 592 fps, +/- 1 pfs. How many FPE is that?

Less than 7 for sure..as long as that is with a "match pellet"

KingSnake
03-24-2008, 05:10 PM
the intent is to keep the match rifles at the lower power and the unlimited is pretty much open.

Yes, you can shoot a Match rifle in Unlimited Class and as far as that goes you could also shoot a Springer rifle in Unlimited class.

There are low powered spring gun/ some are quite accurate that meet the Match rifle power limits and could be shot in all three classes. Generally speaking though, it is not likely that the Springer or the Match rifle will be capable to out shooting a good souped up unlimited rifle on a consistent basis

There is not a velocity requirement in springer, match, or unlimited rifle. Only a power limit for Match rifle

Paul Bendix
03-24-2008, 09:36 PM
Ron,
I am a match director and need help. If a person wins the Match class. How do I test his gun? I have a Chronograph? I take it I also need a scale to weigh the pellets? I have 21 different tins of pellets and the only one with a pellet weight printer on it. A box of crosman premier 10.5 gr. Is there a formular you use to get fpe? I see some online sites you plug the numbers in, but at the range I won't be online. Do you have to chronograph all the Match guns or just the winner?
Thanks for your help.
Paul

Paul Bendix
03-24-2008, 10:17 PM
Ron,
I found the magic number on Pyramyd Air site.

wt in gr. X VOL X VOL
___________________ =fpe

450240


10.5 x671 x671
_____________ =10.5 fpe
450240

With all this math, and I can't find my slide ruler, I will have to take my shoes off and the ground is still frozen.:(

Is there a better way?

Paul

Gary Lemons
03-24-2008, 11:02 PM
Paul,
The Match Class power only has to be verified at Championship matches according to the way I read the rules. Here's what's in the book:

Chronographs
Chronographs must be available to all shooters to determine Match class power in a state, regional or national match.

Gary

KingSnake
03-25-2008, 08:30 AM
I specifically wrote the rules for the Match class such that the match directors really did not have to worry about checking the power rating of the match rifles in their local club matches, especially for this year. Now at the Nationals, you bet, I will be checking the winners and probably spot check a few others just for good measure.
This year being our first year getting started, I wanted to make it as easy as possible on the match directors to run their match smoothly and efficently. I also know that most of the match directors can tell pretty quickly if a rifle is too powerful and can check the rifle if they suspect a rifle not meeting the Match rifle rules.

hoser
03-25-2008, 10:50 AM
Why the rule to require 600 fps or more in the unlimited class?

KingSnake
03-25-2008, 03:33 PM
The greater than 600fps was in the initial set of rules before we adopted the 7fpe requirement in Match class.

If you want to shoot slower than that by all means come on to the match and enjoy the fun.

Robb_H
03-30-2008, 07:18 AM
Sounds to me like you guys need something like this (http://www.airgunbuyer.com/Showproducts.asp?cat=Chronographs&SubCat=Combro%20Chronographs), an indispensible piece of kit.

Dave Shattuck
03-30-2008, 10:49 AM
Robb_H

I had seen these advertised in Airgun World, but never as a close-up. How do they attach to the muzzle as we will have some using barrel shrouds, some using moderators and some with just standard barrel diameters?

As from what I've read, and now seen, I think they're great and if there is enough interest over I'd be willing to contact the manufacturer about sending over a shipment. That is, if there isn't already an importer.

Thanks for the post.

Dave

DonMatzeder
03-30-2008, 11:56 AM
They have proven to be less than accurate. The muzzle blast is what it is measuring for the most part and the short distance between pickups magnifys errors. They won't fit all barrels and cost about the same as a regular Chono and the regular chono is faster to use on multiple guns.

Dave Shattuck
03-30-2008, 12:16 PM
Thanks Don,

As I said; I had seen them only in the ads placed in Airgun World and didn't know enough about them. What you say makes sense.

By the way, I was on the Oehler site this past week and saw how they are no longer making the Model 35. Replacement parts are still available for the 35, but all they are now offering new is a more professional model which costs somewhere around $4500, so I guess it will be a Chrony for me.

Dave

Robb_H
03-31-2008, 10:58 AM
They have proven to be less than accurate. The muzzle blast is what it is measuring for the most part and the short distance between pickups magnifys errors. They won't fit all barrels and cost about the same as a regular Chono and the regular chono is faster to use on multiple guns.
Don,
That's a bold claim and I'd be intrigued to know the source of your information:eek: The only part of the statement that would hold true is the final piece regarding use on multiple guns :)
On this side of the pond they are used extensively by airgunners and renowned for their accuracy and simplicity of use.

Dave,
The unit will attach to any barrell up to about 2" diameter, personally I use a 'velcro' strap on my P70 shrouded barrell but elastic bands do the job just as well.
Have a look at this (http://www.chronoscopes.com/) link to the guy that, makes the unit. Robin is a very helpful guy and I'm sure he'd be pleased to answer any questions.
I have no connection with either Robin nor his company but I do know a good piece of kit when I see it.

Robb

Dave Shattuck
03-31-2008, 12:26 PM
Thanks for the update Robb. Now comes the decision time? I do like the compact design and ease of handling, but I also agree with Don on if multiple guns are to be tested it may be easier to simply set-up a standard chrony once and have everyone shoot through it. Of course, then we would be chancing one of the hot-shot taking out a skyscreen.

Does this unit come with any type of memory, or is that only done through downloading the info directly into a lap-top, which I don't own?

Dave

Robb_H
03-31-2008, 04:08 PM
Dave, I've changed the link to an updated website containing all the instructions and set up guide. The unit does have a memory and will give you an average of any string length.
If you want to try one out I'd be happy to ship mine over for you to field test.;)

Dave Shattuck
03-31-2008, 05:21 PM
Robb,

That is quite a generous offer, and I thank you for it. But, I think I'll say no and just wait a while longer, like at least until Robin has had a chance to re-stock his inventory.

Thanks again for the offer.

Dave

Robb_H
04-01-2008, 08:36 AM
No problem Dave, take care.