Author Topic: Another fowler load question  (Read 4799 times)

billd

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Another fowler load question
« on: April 08, 2010, 11:59:53 PM »
While we are discussing fowler loads on another thread........With the same load, lets say 80 grains of powder and 1 1/4 ounce of shot, in equal length and jugged choked barrels, would you expect a more consistant pattern from a 12 or 10 gauge?  I know barrels vary greatly but lets say theoretically barrels are identical except for gauge.


Bill

Offline sonny

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Re: Another fowler load question
« Reply #1 on: April 09, 2010, 04:31:29 AM »
bill.......looks like ya got a tiger by the tail!.........sonny

Offline Jerry V Lape

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Re: Another fowler load question
« Reply #2 on: April 09, 2010, 06:26:20 AM »
for equal amounts of shot, the larger bore will usually throw the better pattern.  Part of it is the larger bore makes less contact with the shot as it exits the barrel, thereby not deforming as much of the shot.  But a lousy 10ga may be out shot by a great 20g.  And you may be using a little more powder in the larger guage to create the same velocity because the larger bore requires more gas to generate similar pressure. 

Offline Dphariss

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Re: Another fowler load question
« Reply #3 on: April 09, 2010, 06:59:53 AM »
While we are discussing fowler loads on another thread........With the same load, lets say 80 grains of powder and 1 1/4 ounce of shot, in equal length and jugged choked barrels, would you expect a more consistant pattern from a 12 or 10 gauge?  I know barrels vary greatly but lets say theoretically barrels are identical except for gauge.

Bill

Larger bore guns usually perform better with the same weight of shot since they deform fewer shot against the insides of the barrel rounder shot patterns better.

Dan
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Offline James Rogers

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Re: Another fowler load question
« Reply #4 on: April 09, 2010, 03:28:33 PM »

Larger bore guns usually perform better with the same weight of shot since they deform fewer shot against the insides of the barrel rounder shot patterns better.

Dan

ditto!

northmn

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Re: Another fowler load question
« Reply #5 on: April 09, 2010, 08:40:57 PM »
Two things that make the larger bore pattern better, generally.  The shot scrubbing against the barrel is one, but the set back forces against the shot is the bigger one.  1 1/4 ounce of shot in a 10 bore does not have as tall a shot column, which means on firing there is less weight or fewer pellets above the bottom layers which causes deformation.  When you touch off the bottom of the column pushes against the top.  The English used this principle in their double game guns, where many were 12 bore but maybe 2 1/2 chambers and used 1oz to 1 1/16 oz of shot The shot load should also for recoil principles be 1/96 of the weight of the gun, by their reckoning.  Do the math and you see 1 1/16 is 1/96 of a 6.5 pound shotgun.  Another reason larger bores may pattern better with the same charge is that pressures are generally lower.  Turkey shell principle, where they load to low pressures and low velocities to get high center densities.   Use of hard shot or plated shot helps to reduce the setback effects as they deform less.  Right off the top, three of the most useless cartridge loads, partly due to the lack of cushioning, are the 1 7/8 oz 3 inch 12, 1 1/4 oz 3 inch 20 and the 3 inch 410.  As Roster stated about 1 1/2 oz of shot in a 12 is what it will handle.  I have handloaded loads in a 3 inch that convince me of this.  In a ML as the weight of the shot charge goes up more cushioning may be needed, especially in a choked gun.  One of the things Roster wrote about was the use of fiber wads in the shotshell over plastic.  Probably holds for ML's as well.

DP

Offline James Rogers

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Re: Another fowler load question
« Reply #6 on: April 09, 2010, 09:45:19 PM »
Two things that make the larger bore pattern better, generally.  The shot scrubbing against the barrel is one, but the set back forces against the shot is the bigger one.  1 1/4 ounce of shot in a 10 bore does not have as tall a shot column, which means on firing there is less weight or fewer pellets above the bottom layers which causes deformation.  When you touch off the bottom of the column pushes against the top. 
DP
ditto again!