CalendarCalendar   Photos  * FAQ
It is currently Tue Jul 29, 2014 7:43 am

All times are UTC - 6 hours [ DST ]




Post new topic Reply to topic  [ 8 posts ] 
Author Message
 Post subject: Barrel length vs. shot velocity
PostPosted: Mon Mar 08, 2004 10:24 pm 
Field Grade
User avatar

Joined: Thu Jan 29, 2004 4:04 pm
Posts: 24
Location: Leesburg, VA
Does anyone know of any resources that show the velocity of shot through different length barrels (assuming the loads are the same)? Also, with the velocities in resources like Shotgunner's Bible, does anyone know what barrel length they are using? My old man swears that barrel length has absolutely no effect on shot velocity. I disagree even though I don't think the effect is much. Any help is greatly appreciated!


Top
 Profile  
 
 Post subject: Re: Barrel length vs. shot velocity
PostPosted: Tue Mar 09, 2004 1:16 am 
Global Moderator
User avatar

Joined: Wed May 08, 2002 6:16 pm
Posts: 2697
Location: Huntsville, AL
The modern turkey hunter sacrifices pattern performance and velocity for maneuverability of a short 21" barrel. A gun with a 26" barrel will give you higher velocity and better patterns. For every inch up to 26", you gain 7 1/2 to 15 feet per second in velocity, depending upon the gun. A 26" barrel will give you 10 to 15 percent better patterns than a short barrel with the same choke constriction.

From http://www.nitrocompany.com/pattern.htm

_________________
Suas e!

~~There is a very fine line between "hobby" and "mental illness~~

"Women and Cats will do as they please and men and dogs should relax and get used to the idea."--Robert A. Heinlein--


Top
 Profile  
 
 Post subject: Re: Barrel length vs. shot velocity
PostPosted: Tue Mar 09, 2004 9:15 am 
Field Grade

Joined: Wed Mar 03, 2004 2:08 pm
Posts: 87
The Remington site says that all the velocity is acheived in 18" or less. The Nitro Company's claim of 7.5 to 15 FPS per inch equals an average of 60 fps { 10 fps X 10 " }.

It would be enlightening to do an actual test with different bbl lengths and shells.

_________________
cluck cluck cluck cluck cluck
silence silence silence
cluck cluck cluck cluck
silence silence
walk walk walk
drive drive drive
driveway
garage
bed
Repeat at 4:00 am


Top
 Profile  
 
 Post subject: Re: Barrel length vs. shot velocity
PostPosted: Tue Mar 09, 2004 10:04 am 
Crown Grade

Joined: Sun Jan 18, 2004 7:41 pm
Posts: 3159
I am going to throw my 2 cents in here. A couple of months ago my daughter (who is 13) came to me about her science fair project. She wanted to do something with shotguns. We kicked around many ideas and even got a couple of suggestions on this board from Winders and a couple of others. We settled on this issue of barrel length, choke constriction and patterns. We shot several guns of different gauges and barrel lengths and loads. We found many interesting things but the one that was most interesting to me was the 21" 1100 20 gauge and the 28" Verona 12 gauge. With similar factory loads (Remington) and the same distance there was very little difference in the amount of shot percentage wise that was in the target area. In other words where the 12 gauge had (figures are at school but I did some of the math so these are for instance figures) 30% of its shot in the target area (and we used a narrow target area to measure for density) the 20 gauge had 29%. The only difference was when we went to 8 shot (that was the smallest we used). At that point in time there were 7 percentage points difference in the 2. 12 gauge was for instance 32% and the 20 gauge was 25%. With 6 shot there was statistically speaking no difference. This was very interesting. She did quite well on the project and we hope to have the final grade by Friday. 2 of the judges came by together and said they wished they could judge hers. They came back a few minutes later and had traded with 2 others and did grade hers. I think they were kind of amazed that a seventh grade girl would want to do something with shotguns. And what makes it all the better was that it was totally her idea. I told her that she should pick something in some area she was interested in and we would work on it. Shotguns were totally hers.

_________________
In the future, I plan on taking more of an active role in the decisions I make.-Paris Hilton on being booked into jail


Top
 Profile  
 
 Post subject: Re: Barrel length vs. shot velocity
PostPosted: Tue Mar 09, 2004 10:22 am 
Tournament Grade
User avatar

Joined: Sat Dec 27, 2003 6:50 pm
Posts: 113
Location: North Carolina
Just a thought: Would not the type (i.e. burn rate) of the powder have a great deal to do with this? If a very fast powder reaches the max point of the pressure curve when the shot is only 10 or so inches down the barrel, the max velocity of the shot will be reached quickly, and a longer barrel serves no purpose. Conversely, a slower powder reaches max point on the pressure curve later and shot continue to accelerate for a few more milliseconds provided that it is still confined by the gun barrel. One thing for sure, no more acceleration is achieved once the shot leave the barrel.


Top
 Profile  
 
 Post subject: Re: Barrel length vs. shot velocity
PostPosted: Tue Mar 09, 2004 10:53 am 
Diamond Grade
User avatar

Joined: Fri Jan 09, 2004 10:58 am
Posts: 1264
Location: Ogden Ut
Not quite,
The gasses continue to expand even after the powder is all burned up.
I have four different barrels for my 1100, ranging from 22" to 30". Shooting the same load through a crono you would be very suprised at what barrel length changes. On an average there was about 10fps per inch difference all the way up to 30 inch. Different powders did change it some, but not to the extent that I expected.
An interesting side note; with some steel loads (especially the slower ones) about two inches of barrel length equaled one choke size. (1-1/8oz #2s @1300fps a Mod choke in a 22in barrel had an identical pattern % as a Skeet choke in a 30in barrel at 30yds)

tom

_________________
CH Copper Rose Nothing But Net (Patrick)
CH SweetBreez Erin Go Braugh (Peanut)
CH Windflower It's A Beautiful Day (Morgan)
CH SeventhSun Dog Show Barbie (Barbie)
Elite's Sepia Thunder (Blunder)
Raindancers Chasin A dream SH (Meg)


Top
 Profile  
 
 Post subject: Re: Barrel length vs. shot velocity
PostPosted: Fri Mar 19, 2004 5:12 pm 
One of the magazine scribes did an article on this issue a few years ago, I recommend you run a google check - seems like it was Shooting Times, G&A or a similar type rag. Author cut barrels off from a 12 ga. 30" - 2" at a time if I remember. I believe it became notable at 18" inches and shorter.


Top
  
 
 Post subject: Re: Barrel length vs. shot velocity
PostPosted: Sat Mar 20, 2004 7:56 am 
Shooting Instructor
Shooting Instructor

Joined: Fri Jan 30, 2004 5:41 am
Posts: 9945
Location: Cadiz,Ky
Generally speaking.your Dad is correct.Most shot charges reach maximum velocity within 18" of barrel length. Some of the newer,slow burning,powders require a little more barrel to get up to speed--20 to 24 inches. The useful purpose of a longer barrel is in the increased sighting plane and weight distribution(weight forward)for balance. Barrels intended for blackpowder use need to be longer because of the SLOW burning rate of the blackpowder.

_________________
“Fathom the hypocrisy of a Government that requires every citizen to prove they are insured.... but not everyone must prove they are a citizen.”


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 8 posts ] 

All times are UTC - 6 hours [ DST ]


Who is online

Registered users: 31 Pump, 3crosses, BADDUCK, beno, bigalt, Bing [Bot], Bladeswitcher, Bob in Maine, bob9125, Boehler, buddha1950, charlie5b, cw1234, czechmark, Daman, David Radulovich, Dead Dog Fritz, Dealman, ded&ded, DenverDuck, dev1250, dgrebel, Dirtweed, dogchaser37, dubob, eiderz, firedude601, gds45, Google [Bot], Google Adsense [Bot], harvard, hawkeye55, hes, Jim18611865, KarlJ, KRIEGHOFFK80, KStatefan, laxcoach, llc, lucas32, maggs01, mailman, Major146, marsingbob, mike orlen, nanuk, nwtapingtools, Old Reliable, oletymer, PA.CLAYSHOOTER, porsche911er, Redcobra, Riflemeister, sera, shoot-technology, Snotrub, Steve NY, texnekkid, the Rev, thestumper, tvone, Vette Jockey, VictorGK, vinnyd, Wild Skies, Xftrplt


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum

Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group     -  DMCA Notice