Tennis ball - Revision history

Benstern: added and fixed links

2008-06-04T12:51:13Z

added and fixed links

← Older revision		Revision as of 07:51, 4 June 2008
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	== Use and target performance ==		== Use and target performance ==

	Tennis balls are typically launched out of 2.5" sch 40 pipe, and they may be either muzzle or ~~breach~~ loaded. Some recommend putting an inside chamfer on the pipe to facilitate loading.		Tennis balls are typically launched out of 2.5" sch 40 pipe, and they may be either [[Muzzle loading\|muzzle]] or [[Breech loading\|breech loaded]]. Some recommend putting an inside chamfer on the pipe to facilitate loading.

	Due to having to reduce the OD of the tennis ball from ~2.6" to 2.445", there is a significant amount of friction; 2.1 - 2.7 [[psi]], average of 2.5 psi, for a force of about 12 pounds (54 newtons). This complicates loading, slightly reduces muzzle velocity, and during launch will scorch the fuzz on the ball.		Due to having to reduce the OD of the tennis ball from ~2.6" to 2.445", there is a significant amount of friction; 2.1 - 2.7 [[psi]], average of 2.5 psi, for a force of about 12 pounds (54 newtons). This complicates loading, slightly reduces [[muzzle velocity]], and during launch will scorch the fuzz on the ball.

	The inexpensive "fun balls" are slightly smaller, and thus have reduced friction.		The inexpensive "fun balls" are slightly smaller, and thus have reduced friction.

	As an alternative, some use [[SDR]] 21 or 26 2.5", which have IDs of 2.581" and 2.635" respectively.		As an alternative, some use SDR 21 or 26 2.5", which have IDs of 2.581" and 2.635" respectively.

	== Specifications ==		== Specifications ==

Jimmy101: /* Use and target performance */

2008-01-11T19:44:03Z

Use and target performance

← Older revision		Revision as of 14:44, 11 January 2008
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	Tennis balls are typically launched out of 2.5" sch 40 pipe, and they may be either muzzle or breach loaded. Some recommend putting an inside chamfer on the pipe to facilitate loading.		Tennis balls are typically launched out of 2.5" sch 40 pipe, and they may be either muzzle or breach loaded. Some recommend putting an inside chamfer on the pipe to facilitate loading.

	Due to having to reduce the OD of the tennis ball from ~2.6" to 2.445", there is a significant amount of friction (2.1 - 2.7 [[psi, average ~~and median~~ of 2.5 psi, for a force of about 12 pounds (54 newtons). This complicates loading, slightly reduces muzzle velocity, and during launch will scorch the fuzz on the ball.		Due to having to reduce the OD of the tennis ball from ~2.6" to 2.445", there is a significant amount of friction; 2.1 - 2.7 [[psi]], average of 2.5 psi, for a force of about 12 pounds (54 newtons). This complicates loading, slightly reduces muzzle velocity, and during launch will scorch the fuzz on the ball.

	The inexpensive "fun balls" are slightly smaller, and thus have reduced friction.		The inexpensive "fun balls" are slightly smaller, and thus have reduced friction.

Jimmy101: /* Aerodynamics */

2008-01-11T19:41:46Z

Aerodynamics

← Older revision		Revision as of 14:41, 11 January 2008
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	== Aerodynamics ==		== Aerodynamics ==

	The fuzz on the ball increases air resistance above what would be expected of a sphere, to a Cd of about .6 at high velocities. ~~<br>~~		The fuzz on the ball increases air resistance above what would be expected of a sphere, to a Cd of about .6 at high velocities. (See for example this [http://www.aeromech.usyd.edu.au/15afmc/proceedings/papers/AFMC00075.pdf research])
	(See this [http://www.aeromech.usyd.edu.au/15afmc/proceedings/papers/AFMC00075.pdf research])

	This, coupled with the low sectional density of approx. 10.5g/~~inc^~~2 exterior the launcher, cause the unmodified tennis ball to be a short range projectile; range is limited to about 150 yards (~~150~~ meters), even with a powerful launcher.~~<br>~~		This, coupled with the low sectional density of approx. 10.5g/in<sup>2</sup> exterior the launcher, cause the unmodified tennis ball to be a short range projectile; range is limited to about 150 yards (137 meters), even with a powerful launcher.
	It should be noted that this is not necessarily a bad thing.		It should be noted that this is not necessarily a bad thing.

BillyBobJoe at 00:25, 1 February 2007

2007-02-01T00:25:13Z

← Older revision		Revision as of 19:25, 31 January 2007
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	'''Tennis balls''' are hollow, pressurized balls of vulcanized rubber, with a fuzzy felt-like covering, approximately 2.6" in diameter. They are sold in many retail stores (including ~~wal~~*mart) for use in the game of tennis. <br>		'''Tennis balls''' are hollow, pressurized balls of vulcanized rubber, with a fuzzy felt-like covering, approximately 2.6" in diameter. They are sold in many retail stores (including Wal*mart) for use in the game of tennis. <br>
	Somewhat smaller (and significantly cheaper) alternatives with the same basic construction exist, and are marketed as "fun balls" or pet toys.		Somewhat smaller (and significantly cheaper) alternatives with the same basic construction exist, and are marketed as "fun balls" or pet toys.

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	The inexpensive "fun balls" are slightly smaller, and thus have reduced friction.		The inexpensive "fun balls" are slightly smaller, and thus have reduced friction.

	As an alternative, some use [[~~sdr~~]] 21 or 26 2.5", which have IDs of 2.581" and 2.635" respectively.		As an alternative, some use [[SDR]] 21 or 26 2.5", which have IDs of 2.581" and 2.635" respectively.

	== Specifications ==		== Specifications ==

Boilingleadbath: left a word out

2006-08-22T22:01:16Z

left a word out

← Older revision		Revision as of 17:01, 22 August 2006
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	Diameter, unsqueezed: 2.6" (65mm)<br>		Diameter, unsqueezed: 2.6" (65mm)<br>
	Mass, unfilled: 57g<br>		Mass, unfilled: 57g<br>
	Friction: 2.5 psi; 12 pounds (.18 k/cm^2; 54 newtons)<br>		Friction; in 2.5" sch 40: 2.5 psi; 12 pounds (.18 k/cm^2; 54 newtons)<br>


	[[Category:Projectiles]]		[[Category:Projectiles]]

Boilingleadbath: formatting

2006-08-22T22:00:36Z

formatting

← Older revision		Revision as of 17:00, 22 August 2006
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	== Specifications ==		== Specifications ==

	Diameter, unsqueezed: 2.6" (65mm)		Diameter, unsqueezed: 2.6" (65mm)<br>
	Mass, unfilled: 57g		Mass, unfilled: 57g<br>
	Friction: 2.5 psi; 12 pounds (.18 k/cm^2; 54 newtons)		Friction: 2.5 psi; 12 pounds (.18 k/cm^2; 54 newtons)<br>


	[[Category:Projectiles]]		[[Category:Projectiles]]

Boilingleadbath at 21:59, 22 August 2006

2006-08-22T21:59:24Z

New page

'''Tennis balls''' are hollow, pressurized balls of vulcanized rubber, with a fuzzy felt-like covering, approximately 2.6" in diameter. They are sold in many retail stores (including wal*mart) for use in the game of tennis. <br>
Somewhat smaller (and significantly cheaper) alternatives with the same basic construction exist, and are marketed as "fun balls" or pet toys.

== Aerodynamics ==

The fuzz on the ball increases air resistance above what would be expected of a sphere, to a Cd of about .6 at high velocities. <br>
(See this [http://www.aeromech.usyd.edu.au/15afmc/proceedings/papers/AFMC00075.pdf research])

This, coupled with the low sectional density of approx. 10.5g/inc^2 exterior the launcher, cause the unmodified tennis ball to be a short range projectile; range is limited to about 150 yards (150 meters), even with a powerful launcher.<br>
It should be noted that this is not necessarily a bad thing.

== Modifications ==

The friction required to load a tennis ball in a 2.5" sch 40 barrel is about 12 pounds [http://forums.spudtech.com/topic.asp?TOPIC_ID=14446]. If one finds this excessive, they generally correct the problem by burning the fuzz off.

Additionally, one may seek to increase the range or damage capabilities of the tennis ball. This generally entails weighting the tennis ball by injecting water, or inserting pennies or other small, dense objects. [[Optimal mass]] increase may be calculated with repeated trials using the [[GGDT]]'s integral ''external ballistics calculator''.

== Use and target performance ==

Tennis balls are typically launched out of 2.5" sch 40 pipe, and they may be either muzzle or breach loaded. Some recommend putting an inside chamfer on the pipe to facilitate loading.

Due to having to reduce the OD of the tennis ball from ~2.6" to 2.445", there is a significant amount of friction (2.1 - 2.7 [[psi, average and median of 2.5 psi, for a force of about 12 pounds (54 newtons). This complicates loading, slightly reduces muzzle velocity, and during launch will scorch the fuzz on the ball.

The inexpensive "fun balls" are slightly smaller, and thus have reduced friction.

As an alternative, some use [[sdr]] 21 or 26 2.5", which have IDs of 2.581" and 2.635" respectively.

== Specifications ==

Diameter, unsqueezed: 2.6" (65mm)
Mass, unfilled: 57g
Friction: 2.5 psi; 12 pounds (.18 k/cm^2; 54 newtons)

[[Category:Projectiles]]