Velocity differences between 24" and 7"

[matt45]

Hello the Camp,
     I just finished testing two loads in my Henry and my Schofield.  A smokeless load (5.0 grs. Bullseye/200 gr cast) had a velocity of 956 fps. in the Henry, and 717 fps in the Schofield- A 239 fps difference.  The B.P. load was 892 for the Henry; 675 for the Schofield, a 217 fps difference. 
     Now I've got to clean the darn things

[Trailrider]

About 12-14 ft/sec/inch. About right, regardless of caliber.

[matt45]

The caliber is 45 S&W (Schofield).

[Coffinmaker]

OK.  That does it.  I'm gonna cut one of my Henrys down to 7 1/2 inches ................  :-)

Coffinmaker

[Sir Charles deMouton-Black]

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[w44wcf]

Hello the Camp,
     I just finished testing two loads in my Henry and my Schofield.  A smokeless load (5.0 grs. Bullseye/200 gr cast) had a velocity of 956 fps. in the Henry, and 717 fps in the Schofield- A 239 fps difference.  The B.P. load was 892 for the Henry; 675 for the Schofield, a 217 fps difference. 
     Now I've got to clean the darn things

Matt,
Thank you for your test results. Just curious.....what was your b.p. load?
36 grs. FFG typically gives 1,200 f.p.s. in my .44-40 '73 (21" barrel).
Interesting in a 24" barrel, the velocity gain was only 21 f.p.s. for the additional 3". 

w44wcf

[matt45]

     These were pretty anemic- by weight they measured 28 grs.  I was experimenting w/ spg wads to reduce fouling in the Uberti Schofield.
     

[matt45]

 
... and in case you weren't tired of hearing fom me.
      The actual difference is =/- 250 fps.  Slightly more than the rule of thumb 10 fps per " of barrel

[rickk]

some of the loss might be from the barrel/cylinder gap as well.