CMP Rimfire Sporter definition is as follows:
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=============================RIFLES ALLOWED.
Rifles used in the Rimfire Sporter Rifle Match must be standard sporter-type rimfire rifles that meet the following requirements:
Overall weight of the rifle may not exceed 7 ½ pounds, with sights and sling (if a sling is used).
The stock may have a sling swivel, but it must be fixed in one location (rails with adjustable sling swivels are not permitted). Thumbhole stocks, adjustable butt plates, adjustable cheek pieces and rails or adjustable (moveable) sling swivels are not permitted.
Any safe rimfire rifle with any type of action may be used. Rifles should have a magazine capable of holding five rounds so that it can be used during rapid-fire stages. Single shot rifles are permitted, but using a single
shot to fire five shots in 30 seconds in rapid-fire is difficult. Rifles with clip, box or tube-type magazines may be used, however, tube magazines are more difficult to reload quickly during rapid-fire shooting.
The trigger must be capable of lifting a three-pound weight when cocked.
Telescopic, receiver or open sights may be used. Shooters who use rifles with telescopic or receiver (aperture) sights compete in the T-Class. Scopes are limited to six power (6X). If a variable scope is used, the
power adjustment may not exceed 6X and it must be taped in that location. Any rifles with receiver (aperture or ‘peep’) sights must be used in the T-Class. Shooters who use rifles with open sights compete in the
O- Class.
A standard leather or web sling no wider than 1 ¼ inches may be used in the prone and sitting or kneeling positions. Slings may not be used in the standing position, but may remain on the rifle.
4-H has added an interpretation of the rules (2005 Event Synopsis):
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=============================In accordance with the intent of this match - barrels of special composition (carbon) or non-factory styles(i.e. fluted) are not permitted. Sporter rifle barrels only.
Finally my question:
Are .920 (no taper) target barrels allowed?
They seem to have inserted confusion when they state non-factory styles not allowed and then say sporter barrels only.
It seems to me that they would not be, as I conclude a sporter barrel has a taper. But, I'm willing to learn.