Bore-Up

Tempest VI · October 5th, 2010, 14:24

I have a CA AUG, but the fps was very low (180 fps) and the range was also not good. So, researching the problem, I came to the conclusion that the hop-up bucking was done. So I changed that out and it seemed to work a bit better. I haven't had a chance to go and test it fully again, but I read up on something else. I upgraded my barrel to a 6.03x590mm. Does this mean I need a bore-up kit for the more air needed in the barrel? Or would I be fine with the stock size? Do I need to have a cylinder/barrel ratio just greater than 1 or higher?

ThunderCactus · October 5th, 2010, 14:30

550 is the max length on full cylinders, so you need a bore up kit.
Why do you need a 590mm barrel?

Boyso · October 5th, 2010, 14:53

And I'd test the gun with a stock barrel first, to help you find the problem.

But yeah, 590mm is freaking long.

Styrak · October 5th, 2010, 20:51

No, you don't need a boreup kit on a 590mm barrel.
My AUG had an extended outer barrel and a 590mm inner and it was fine.

Amos · October 5th, 2010, 22:22

you don't NEED.

but to make use of the barrel, you VERY MUCH SHOULD have one past 550mm.

THe_Silencer · October 6th, 2010, 03:06

Definitely be nice to have; try it out and see how it affects performance.

Short Round · October 6th, 2010, 11:41

This is my main problem now too. A bore up will help but it might not be a big improvement. Here's what i suggest

1: Ignore this step, see below post. *Thanks stryak

2. Hop up rubber, although you have it installed it may no be properly fitted into the unit. Now that is my current problem, you may not have that problem, I wouldn't know haha

3. O-Ring around the Piston head, this is a second problem I have now. If the O-ring is not perfectly fitted for your cylinder and piston head, the airseal will be very weak.

4. Spring, my third problem, check which kind of spring you have, mine is currently all weared out and bent out of place so its not performing to it's expected self.

5. Piston, your piston's teeth may be weared out.

Pretty much it could be ANYTHING lol, I may suggest taking it to a gun doc

Styrak · October 6th, 2010, 12:28

Quote:

Originally Posted by Najohn

1: Make sure the port on the cylinder is facing towards the back of the gearbox, I did this and my FPS/airseal went horrific.

AUG's have non-ported cylinders FYI.

noypi · October 6th, 2010, 12:53

Apart from what was mentioned. Also check if there is some play/ gap between the butt plate and the gearbox, this can affect the seal of the air nozzle to the hop up which cause a significant drop in FPS.

m102404 · October 6th, 2010, 13:04

These might be two different things really...

1. Over 550mm and you're into boreup range...I think at 590 you would be in for a kit. You'd definitely have a full cylinder...LOL, don't know how that got into this...

2. Airseal (note...I've only worked on TM AUGs...so dunno if the CA one differs significantly). Aside from within the mechbox itself, there's two things that can greatly affect the airseal between the nozzle and hopup unit/rubber. The positioning of the mechbox in the stock and the assembled position of the front end.

Typically, as long as nothing is broken in the stock, it's not too hard to ensure that the mechbox is pushed/held forward securely.

With the front end assembled, check that there isn't any back/forth play that would end up moving the barrel assembly (thus the hopup/rubber) away from the mechbox/nozzle. On some of the ones I've seen the cross bolt that you'd push to the side to release the front end can get worn...allowing the front end to move around (compromizing the air seal). I think on the last one I worked on I rebuilt the engagement surface of the bolt...(might have built up the lug that it bears against and just tidied up the cross bolt...can't remember). End result was that the front end was held tight in place and FPS/consistency picked right back up.

Best of luck

(of course the simplest way to test if you need a bore up for your rifle is to try another inner barrel that's shorter....)

Home	Forums	Register	Gallery	FAQ	Calendar
Retailers	Community	News/Info	International Retailers	IRC	Today's Posts

British Columbia	Alberta
BCAC	EAR
Op-For	JOC
Northern Arms Airsoft	Skunkworx Airsoft
Airsoft Kelowna	RAAT
Prince George Airsoft	Manitoba
Saskatchewan	MAA
SK Airsoft	Ontario
PDW	Airsoft Ottawa
South Sask Mercs	Snow Dragons
Quebec	1st Ranger Platoon
PQAC	Wolfpack Tactical
1st Pathfinders Regiment	TTAC3
Quebec Airsoft
MTX Airsoft	Atlantic
FAQc	Atlantic Airsoft

October 5th, 2010, 14:24	#1
Tempest VI Trader rating Join Date: Apr 2010 Location: Pembroke, ON	Bore-Up I have a CA AUG, but the fps was very low (180 fps) and the range was also not good. So, researching the problem, I came to the conclusion that the hop-up bucking was done. So I changed that out and it seemed to work a bit better. I haven't had a chance to go and test it fully again, but I read up on something else. I upgraded my barrel to a 6.03x590mm. Does this mean I need a bore-up kit for the more air needed in the barrel? Or would I be fine with the stock size? Do I need to have a cylinder/barrel ratio just greater than 1 or higher?

October 5th, 2010, 14:53	#3
Boyso a.k.a. LastSpartan Trader rating Join Date: Jul 2009 Location: Québec city	And I'd test the gun with a stock barrel first, to help you find the problem. But yeah, 590mm is freaking long. __________________ NEW BACON FOR SALE! "WHEN I DIE BURY ME UPSIDE DOWN SO THE WORLD CAN KISS MY ASS" -Platoon

October 5th, 2010, 20:51	#4
Styrak Trader rating Join Date: Jan 2007 Location: Saskatoon, SK	No, you don't need a boreup kit on a 590mm barrel. My AUG had an extended outer barrel and a 590mm inner and it was fine. __________________ Airsoft Sales and Repair/Upgrade Services

October 5th, 2010, 14:30	#2
ThunderCactus Not Eye Safe, Pretty Boy Maximus on the field take his picture! Trader rating Join Date: Feb 2007	550 is the max length on full cylinders, so you need a bore up kit. Why do you need a 590mm barrel?

October 5th, 2010, 22:22	#5
Amos Trader rating Join Date: Aug 2006 Location: Tokushima, Japan	you don't NEED. but to make use of the barrel, you VERY MUCH SHOULD have one past 550mm. __________________ Custom Builds: FA3674U Krinkov G3SD6

October 6th, 2010, 03:06	#6
THe_Silencer Trader rating Join Date: Jul 2009 Location: Hamilton,ON	Definitely be nice to have; try it out and see how it affects performance. __________________ It is the mark of an educated mind to be able to entertain a thought without accepting it - Aristotle -Founder of Steel City Hamilton Infantry and Tactics -Certified level 43 Autosniper by Commander Amos

October 6th, 2010, 11:41	#7
Short Round Najohn Trader rating Join Date: Aug 2009 Location: SkyDome	This is my main problem now too. A bore up will help but it might not be a big improvement. Here's what i suggest 1: Ignore this step, see below post. Thanks stryak 2. Hop up rubber, although you have it installed it may no be properly fitted into the unit. Now that is my current problem, you may not have that problem, I wouldn't know haha 3. O-Ring around the Piston head, this is a second problem I have now. If the O-ring is not perfectly fitted for your cylinder and piston head, the airseal will be very weak. 4. Spring, my third problem, check which kind of spring you have, mine is currently all weared out and bent out of place so its not performing to it's expected self. 5. Piston, your piston's teeth may be weared out. Pretty much it could be ANYTHING lol, I may suggest taking it to a gun doc __________________ Last edited by Short Round; October 6th, 2010 at 12:56..*

October 6th, 2010, 12:53	#9
noypi Trader rating Join Date: Jun 2007 Location: Oakville	Apart from what was mentioned. Also check if there is some play/ gap between the butt plate and the gearbox, this can affect the seal of the air nozzle to the hop up which cause a significant drop in FPS.

October 6th, 2010, 13:04	#10
m102404 Tys Trader rating Join Date: Apr 2006 Location: Toronto	These might be two different things really... 1. Over 550mm and you're into boreup range...I think at 590 you would be in for a kit. You'd definitely have a full cylinder...LOL, don't know how that got into this... 2. Airseal (note...I've only worked on TM AUGs...so dunno if the CA one differs significantly). Aside from within the mechbox itself, there's two things that can greatly affect the airseal between the nozzle and hopup unit/rubber. The positioning of the mechbox in the stock and the assembled position of the front end. Typically, as long as nothing is broken in the stock, it's not too hard to ensure that the mechbox is pushed/held forward securely. With the front end assembled, check that there isn't any back/forth play that would end up moving the barrel assembly (thus the hopup/rubber) away from the mechbox/nozzle. On some of the ones I've seen the cross bolt that you'd push to the side to release the front end can get worn...allowing the front end to move around (compromizing the air seal). I think on the last one I worked on I rebuilt the engagement surface of the bolt...(might have built up the lug that it bears against and just tidied up the cross bolt...can't remember). End result was that the front end was held tight in place and FPS/consistency picked right back up. Best of luck (of course the simplest way to test if you need a bore up for your rifle is to try another inner barrel that's shorter....)

Bore-Up

General