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cr1mson
03-30-2006, 04:57 AM
I have an 03 Imagine, running CO2 with remote, 14" PMI barrel, with aluminum ACS bolt (broken in with about 15,000 shots total). I have totally cleaned the gun and checked everything on it. I only get about 210 at chrono. I changed the bolt back to stock with this being the only change, and I got 385 fps at chrono. Is this usual for the ACS bolt to eat that much velocity?

nitrobassboats
03-30-2006, 06:27 AM
i dont beleve so also being aluminum acs the only dif is the spring inside the bolt,does it feel smooth whenn u cock it something isnt right
nitro

cr1mson
03-30-2006, 07:58 AM
yes, smooth when I cock it. I don't see any visible burrs or anything to slow down the ACS. I don't know what the prob is, but I am not using the ACS right now. I am probably going to get rid of it if no one can figure this out.

NB_Hacker_NB
03-30-2006, 12:33 PM
Use a low tension spring. It's the black one in the 32* Kit.

big_daddy_d
03-30-2006, 12:51 PM
Not enough air flowing through it?

nitrobassboats
03-30-2006, 02:42 PM
Not enough air flowing through it?
dad u have a point,this is the correct bolt im assuming for an imagine
might seem dumb but measure it beside the stock bolt and air inlet(the oval)
shape on the bottom and see if they match up,i use the delrin acs and have
2 i switch back and forth on my lpb 04 i get no difference on velocity
seems something is not being where its supposed to be is all.
nitro:(

nitrobassboats
03-30-2006, 02:44 PM
Use a low tension spring. It's the black one in the 32* Kit.
thats the spring i use with a shocktech shim kit silver to get it down to
280 fps and also the black valve spring

druid
03-30-2006, 03:00 PM
It seems that everyone that gets an ACS bolt has velocity problems - whether it's delrin or aluminum.

I suggest a different bolt...like a lightening bolt, a spudn'kd (if you can find one) or a sunbear that "eaglelox" on this forum makes. His site is HERE (http://insanepainsports.com/page2.html)

Hob Hayward
04-04-2006, 01:56 PM
Weird, In otter's test he got like 5 fps slower than the stock bolt, but his site is gone right now for some reason... Hacked? So I can't bring up the table.

ooglieboogliebob
04-04-2006, 04:39 PM
well ... different guns work differently ... so there could be fluctsations between other guns ...

NB_Hacker_NB
04-04-2006, 05:18 PM
thats the spring i use with a shocktech shim kit silver to get it down to
280 fps and also the black valve spring

I ment with the stock bolt.

NitroBall
04-04-2006, 06:30 PM
In a real world, i cannot see how changing a bolt can make such a difference in FPS .
From 210 fps to 385 fps ?
is the chrono reading and working fine ? 175 fps difference ?

Hob Hayward
04-04-2006, 07:31 PM
Hmm just a theory, but how long have you been using the ACS? I'm thinking if its broken in too much the spring depresses due to inertia, the front staying back, and thus the air not going directly onto the ball?