hello everyone
i'm going through my first built of a spudgun, and i'm gathering the parts and doing research. I'm gonna use a 75mm barrel, but the valve i found is 1/2" in diameter. Will  this difference in diameter impact my pressure/firing distance?
            
			
									
						question about valves
- jackssmirkingrevenge
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You must think in terms of cross-sectional area.
In this case, 75mm is almost 6 times greater than 12.7mm, but in terms of area it is a whopping 35 times greater.
This is not a recipe for good performance.
The effects of the Square-cube law are quite pervasive in this hobby.
Finding a bigger valve commercially is going to cost you, so consider building your own or using something simple but effective like a burst disk.
            
			
													In this case, 75mm is almost 6 times greater than 12.7mm, but in terms of area it is a whopping 35 times greater.
This is not a recipe for good performance.
The effects of the Square-cube law are quite pervasive in this hobby.
Finding a bigger valve commercially is going to cost you, so consider building your own or using something simple but effective like a burst disk.
					Last edited by jackssmirkingrevenge on Tue May 19, 2020 3:42 am, edited 1 time in total.
									
			
						hectmarr wrote:You have to make many weapons, because this field is long and short life
- farcticox1
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127mm or 12.7mm
            
			
									
						- jackssmirkingrevenge
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Good catch, edited.
hectmarr wrote:You have to make many weapons, because this field is long and short life


