Author Topic: vent size  (Read 2995 times)

Offline little joe

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vent size
« on: May 04, 2013, 04:40:31 PM »
I,m shooting 3f and priming with 4f. What size vent hole do you guys use?  

Offline Pete G.

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Re: vent size
« Reply #1 on: May 04, 2013, 05:06:22 PM »
1/16"

Offline SCLoyalist

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Re: vent size
« Reply #2 on: May 04, 2013, 05:09:04 PM »
1/16" for starters has never given me any ignition problems.   The hole will enlarge over time from gas erosion.   I think the last vent liner I replaced because it had gotten too large had gotten up somewhere around 3/32".   A White Lighting liner comes with less than a 1/16" diameter; Drilling it out to 1/16" at installation seems fairly common practice.   Too small a diameter and you are more prone to misfires (but get less muzzle velocity variation), too large and you can push a little main charge powder out the vent during loading.  

Your question seems like something that Larry Pletcher would possibly have an article and test data  on over on his website.

Offline wattlebuster

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Re: vent size
« Reply #3 on: May 04, 2013, 05:51:36 PM »
1/16th works real good for me  ;D
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Offline hanshi

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Re: vent size
« Reply #4 on: May 04, 2013, 09:14:17 PM »
1/16"
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Offline bgf

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Re: vent size
« Reply #5 on: May 05, 2013, 02:45:19 AM »
1/16 is all I need and it works well for 2f and 3f.  I tried 5/64" and 3F starts coming out (Graf's, which is a little smaller grain size than Goex), but you could probably go all the way to 3/32" for 2F Goex and it would likely never plug, although you'd be venting some pressure.  The smaller holes (under 1/16") worked well with 3F Swiss, but caused problems (fouling) with other powders.  I agree with SC Loyalist for 3F -- when the hole gets ~>3/32" it is time for replacement, sometimes before.  It will start to shoot a little funny and erosion goes faster and faster -- at least that is what happened to me.
« Last Edit: May 05, 2013, 03:05:00 AM by bgf »

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Re: vent size
« Reply #6 on: May 05, 2013, 03:14:41 AM »
I,m shooting 3f and priming with 4f. What size vent hole do you guys use?  
I drilled mine out to 1/16 works good