Bang bang, chuff, bang.

[fifthmag]

Hi guys, I've posted this here as I am unsure as to the cause of this minor problem.

I have RTP like many here (albeit completely aftermarket on the outside big thanks to RGP, Deadlywind and White Wolf for their sexifying services to Mags) with a ULT. After a bit of tuning with help from some of the members here (thanks to Dayspring) my mag runs basically well. However I do get periodic chuffing when I'm dry firing to lube the works, which gets more frequent with higher ROF's. I have observed less incidences of this when actually playing, but I'm still getting chuffs in the middle of a string. My setup is as follows, #0 carrier, 2 shims, ULT 5 shims. Less shims in my ULT and it is a bit sluggish, more and it bounces. Air is a 45/centreflag, nominally at 800 psi but this is not confirmed. Tried revvies and ricochet loader (and the appallingly badly made Rolader II, but that is another story.....)

Could air input pressure affect the reset speed (it almost feels as if the gun isn't keeping up sometimes) or perhaps a loader issue?

Any help will be sincerely appreciated.

Many thanks!

[fifthmag]

Thanks for the speedy reply! Great to hear from you. I've just yesterday gone down to the smallest carrier as it just started to leak with the next size up, so I assume I'll be sticking with that one.

I can rule out the loader then, as I'm not fast on the trigger by any stretch. Leaving either recharge, or shims in the LX. I understand that shims affect the point at which the bolt resets - I did add one yesterday to see if it made a difference, but it seemed much the same. Would that alter your advice?

Many thanks, Wayne, NZ

[fifthmag]

I must put this correction in respect of my original post - I meant "RPG" not "RGP" and "reloader" not "rolader". Apologies for the typo, and my inability to type and check my spelling.

Long live the chimera!

[athomas]

Check that the detents aren't sticking.
How old is the bolt spring? An older one may be worn or weak slowing the reset.
Make sure the regulator pin assembly is free of debris.
Make sure the trigger rod is the proper length (not touching the trigger back) so the on-off fully opens.
Try changing your carrier oring and redoing your level 10 setup. Do this without any shims in the level 10.

[fifthmag]

Hi there Athomas,

The spring, along with most of the gun is less than 10 months old. I've just gone down to carrier 0 when the .5 started to leak, in the last couple of days. The spring is the silver spring (as of yesterday) as I was still smashing the odd ball with the red. I have a dallara body, in which the detents are normally stuck in too far, which I've remedied with an additional o ring either side which now just holds a ball in place.

I'll take the shims out, but as RogueFactor above suggested putting one in, I'm not sure what I'm aiming for with the adding and subtracting of shims in the level X?

[athomas]

I really think you should change your carrier oring. 0 is small. If it is bad, you would have to use a carrier that is too tight in order to prevent leakage. Then, to compensate, you would have to increase the pressure in the chamber (ie; velocity setting). This would cause chopping, even with a stiff spring.

Adding or subtractig shims in the level 10 changes how far the bolt has to travel before the air is allowed to escape from the vent hole in the case of a blockage in the breach. If you hear the chuff sound, then the bolt is going far enough. If you get forward movement of the bolt (not a full cycle) and it sticks after stopping on a blockage, then you need to add a shim or two to bring the carrier farther down the powertube to shorten the required travel distance.

[fifthmag]

Many thanks, I'll retune the bolt and start again. I'll let you know how I get on, and thanks for the advice. Much appreciated.

[fifthmag]

Update. I started again with a completely different carrier and ring, the 1.5 carrier, no shims as yet. The chuffing is gone, but it leaks slightly and intermittently. If it is constant, is it still the carrier? I have the 2nd spring down installed but the bolt movement is still pretty violent. I'll chrony this weekend, but if the velocity range is good should I go up to the biggest spring, or is this where shims come into play.

many thanks, Wayne

[athomas]

If its leaking at all, then its probably that the carrier size is too large.

If its hitting the ball too hard in the desired velcocity range, use a stiffer spring. Check your velocity range first.

Add shims only if you get bolt stick after the bolt hits something in the breach and won't reset.

[fifthmag]

Cheers Athomas, I will do. Your assistance is much appreciated.

[fifthmag]

Many thanks athomas, the help is most appreciated. I'm using a number 1.5 carrier now with no shims. I tried my new HALO on it yesterday for half a case, and had no breaks and 1 chuff, which was probbaly me short stroking.

I'm not quick on the trigger by any stretch but the HALO appears to have stopped one thing, the possibility of a ball not being in the breech when I pull the trigger. As I shoot marballiser all the time, for both my phantom and Mag it does seem a little more resistant to breaking in breech, so I 'll hold off adding LX shims fro now.

Thanks again!

[athomas]

If you find that you have problems with the bolt sticking forward following a failed shot due to a breach jam or some other reason that prevented the bolt from cycling forward, then you can add LX shims. Otherwise, you probably won't ever need them anyway.

[fifthmag]

Roger that athomas, thanks for the assistance. Have yourself a great Christmas!

[Chris_automag_07]

what kind of tank are you running?....i had a 45/3000 steel aci bulldog tank and on that my mag shot horribly, and a nitroduck 68/3000 and it shot ok, but now i have a flatline and it shoots amazing.

[fifthmag]

I currently have a centreflag hyperflow 420 reg, but I think I might get myself a MacDev Legionaire for my birthday. I was thinking of a 4CE reg on a 70 stubby but the centrefire website inexplicably didn't have them when I checked. So MacDev it will be.