Welcome Guest [Log In] [Register]
Welcome to Central Pennsylvania Airsoft. This forum serves the Central Pennsylvania Airsoft community, helping to unite players and further promote the growth of airsoft in the area.


You're currently viewing our forum as a guest. This means you are limited to certain areas of the board and there are some features you can't use. If you join our community, you'll be able to access member-only sections, and use many member-only features such as customizing your profile, sending personal messages, and voting in polls. Registration is simple, fast, and completely free.


Join our community!


If you're already a member please log in to your account to access all of our features:

Username:   Password:
Add Reply
New inner barrel
Topic Started: Aug 13 2011, 10:28 PM (798 Views)
Vanish
Member Avatar
Elite Member
[ *  *  *  *  * ]
I just got my new barrel for my M14 installed :D and I ran about 200 round balls threw it.
Madbull 7075 6.01 tight bore inner barrel
Shoots pretty good for my initial run threw. I used a cheaper bucking for this try but plan to use a better madbull fishbone red after I finish polishing and a couple other mods I'm doing.
I have it out for the mods now. I only put it in to get a before and after comparison. I'll post weather or not I see any differences from the polishing and the filed down port.
Strategy without tactics is the slowest route to victory. Tactics without strategy is the noise before defeat.
-Sun Tzu



Metal Gears Tactical
MetalGearsTactical@gmail.com
Alcohol doesn't solve your problems but then again milk doesn't either.
Offline Profile Quote Post Goto Top
 
Nova
Member Avatar
Polar98 CO
[ *  *  *  *  *  *  *  *  *  *  *  * ]
Sounds good Vanish. I have a madbull 6.01 for my M16 as well. It has served me well.
Online Profile Quote Post Goto Top
 
Swift
Member Avatar
2000+ posts
[ *  *  *  *  *  *  *  *  *  * ]
I have a Madbull as well but may switch to an EDgI
Never a failure, Always a lesson.

Member of ASOG
Offline Profile Quote Post Goto Top
 
Vanish
Member Avatar
Elite Member
[ *  *  *  *  * ]
I looked at Edgi and think they're a little expensive. I want to see how this will do and its half the price. In the future I may get one to compare and see if its worth the added cost.
Strategy without tactics is the slowest route to victory. Tactics without strategy is the noise before defeat.
-Sun Tzu



Metal Gears Tactical
MetalGearsTactical@gmail.com
Alcohol doesn't solve your problems but then again milk doesn't either.
Offline Profile Quote Post Goto Top
 
surfer
5000+ posts
[ *  *  *  *  *  *  *  *  *  *  *  * ]
I was sort of confused as to why you'd do that (Bagel). Madbull makes really nice barrels I thought. I'd think that there's be a miniscule difference. But I haven't owned either brand actually.
Offline Profile Quote Post Goto Top
 
Nick923
Somewhat New
[ *  * ]
I've used a Prometheus barrel in my M16 and I must say the range I got from it was incredible when the hop up settled in. Took a little bit of playing around with it, but I was pulling I think 130+ ft shots like nothing with .25g bbs. I even had a Prometheus barrel for an M14 but that was a very troublesome gun, so unfortunately I never got the results from it and sold the gun for parts, but I still have the barrel around somewhere. Sad to say but I think the barrel is worth more than the gun.
Offline Profile Quote Post Goto Top
 
DoubleA (AA)
Member Avatar
Gray Ghosts CO
[ *  *  *  *  * ]
@vanish: the link for your mad bull barrel shows it a 509mm. That is the exact barrel I bought for my Socom Noveske m4 that I am currently having rebuilt as a DMR.
I was curious why you went that short for an m14. I would have thought you would have went longer for accuracy. I was thinking about going to a 600mm myself.
The guy rebuilding my gun says it will be 450 fps with .25 bb's so I had him make it semi auto only so I could use it at commercial fields since they restrict full autos shooting that hot.
ASOG (Airsoft Special Operations Group) Member

National OPs Attended:
Operation Lion Claws - Red Storm East 2012, Irene 2012
Regional OPs:
SOG Field Maryland - Firestorm, Sunset
West Chester PA - OP Longstreet
Local OPs:
Polar98- Night Hawk V & VI, Blackside I, Blue Wing I & II, Eclipse III.


ASOG Team Members Originations: Lancaster/York PA & Ringoes NJ
Team Facilty: Kill Barn (CQB Training Facility) Location: Ringoes NJ



Offline Profile Quote Post Goto Top
 
Vanish
Member Avatar
Elite Member
[ *  *  *  *  * ]
4mula1, A few things came into play with going to a 509mm. It is the length that best fits the stock outer barrel but that isn't the main reason.
I chose for 2 main reasons.

First, I've been reading some newer and older trials on barrel lengths and found that alot of techs say that the real steal theory of longer is better doesn't apply to airsoft. Alot of what I was reading said that after a barrel reaches a certain point (509mm+) there is not any real difference in the level of accuracy you will get from it. At these longer lengths the importance of length isn't as valuable as quality of the barrel.
(These numbers are made up but I'm only using this as an example), If a 455mm barrel is 20% more accurate than a 363mm being 92mm longer. Then a 600mm barrel being 91mm longer than a 509mm should also be 20% more accurate, but it isn't, its actually only 7% more accurate because the %s drop exponentially at longer lengths. If you understand what I'm saying. lol

Secondly, I've been doing some figuring and found that volume matching my inner barrel to my cylinder will produce an overage of air volume in the cylinder. This overage of air can help determine the weight of the BBs I should use to max out the air pressure without creating excess turbulance at the muzzle.
Use this formula: Volume = 3.142 X Radius squared X Height
And the radius of most regular (non B-up) cylinders is 22mm. B-up are generally 23mm.

By knowing the volume of the cylinder (be sure to calculate lost space in the cylinder for your piston head setup, AoE, and any spacers or sorbos) (Also subtract any lost space from the cylinder for the cylinder head placement) you can find the max volume of the cylinder and then subtract to get the max volume of any potential inner barrels. The ratios to find the BB weight by the overage in air volume differ depending on where you look (I can explain variables in BB size/weight another time) but with the numbers I worked up I decided that I wanted no more than 16,500 cubic mm in volume (581.6mm 6.01 inner) so I settled on a 509mm with 14,441.52032195 cubic mm of volume so I can use a heavier BB and still retain energy. And it fits perfectly with no need to add a moch supressor.

I know that wasn't the answer you were expecting but its how I came to my decision. :P
If you have any questions or need help with your DMR just say something and I'd be happy to offer an opinion.

I also forgot to mention- The formula for calculating the cylinder's bore is the same furmula to calculate the inner barrel's bore too.
Edited by Vanish, Aug 16 2011, 03:20 PM.
Strategy without tactics is the slowest route to victory. Tactics without strategy is the noise before defeat.
-Sun Tzu



Metal Gears Tactical
MetalGearsTactical@gmail.com
Alcohol doesn't solve your problems but then again milk doesn't either.
Offline Profile Quote Post Goto Top
 
Nova
Member Avatar
Polar98 CO
[ *  *  *  *  *  *  *  *  *  *  *  * ]
I believe that the length that improvements are no longer significant is somewhere around the standard AUG/M16 length depending on the FPS of the gun. I read this somewhere last fall and can't seem to find the source currently.
Online Profile Quote Post Goto Top
 
Vanish
Member Avatar
Elite Member
[ *  *  *  *  * ]
Nova
Aug 16 2011, 03:16 PM
I believe that the length that improvements are no longer significant is somewhere around the standard AUG/M16 length depending on the FPS of the gun. I read this somewhere last fall and can't seem to find the source currently.
Probably what I was reading. :D

And AUG/M16 standard length is 509mm.
Strategy without tactics is the slowest route to victory. Tactics without strategy is the noise before defeat.
-Sun Tzu



Metal Gears Tactical
MetalGearsTactical@gmail.com
Alcohol doesn't solve your problems but then again milk doesn't either.
Offline Profile Quote Post Goto Top
 
1 user reading this topic (1 Guest and 0 Anonymous)
ZetaBoards - Free Forum Hosting
Create your own social network with a free forum.
Learn More · Register for Free
Go to Next Page
« Previous Topic · Airsoft Firearms/Gear · Next Topic »
Add Reply

Current weather conditions in our community

Latest Pequea, Pennsylvania, weather Latest Potter County, Pennsylvania, weather Latest Hagerstown, Maryland, weather

Latest Bellefonte, Pennsylvania, weather Latest York, Pennsylvania, weather Latest Elkins, West Virginia, weather

Latest Gettysburg, Pennsylvania, weather Latest Bedford, Pennsylvania, weather Latest Altoona, Pennsylvania, weather