Open Class Carter Buzzard

[Moodog]

Recently purchased but the seller forgot to mention that it leaked and did not shoot at a playable velocity. I have since fixed the leak but regardless of what I do I cannot get it to shoot above 170FPS. I have tried all sorts of different spring combinations, but I believe the problem is something with the internals. When you adjust the IVG more inward the sear no longer catches on the bolt, despite having standard nelson springs. Sizers are .689 and .686, someone drilled the frame for a bottom line and did not do the most elegant job. I no longer want to fight with this - I am just trying to get what I have in it.

SOLD

[Walker]

I will take it.... Send me your PayPal.........

PM Sent................23:47


Walker

[Walker]

Payment sent.........


Walker

[BOOSH]

what did it sell for?

[russc]

Condition: frustrating 🤣

Would also love to know the sell price

[Socalpumpballer]

Sounds like a powertube issue. I’m guessing it’s too long and choking the air

[Snowpuff]

What was the output pressure of the bottle you used to test it with? They need like 1k or just c02 cause that's at 1k

[Chuck E Ducky]

Co2’s sweet spot is more like 825-850psi I find just about anything designed to run on CO2 will run on HPA at that pressure unless designed to run on liquid CO2

Carters usually like to run around 850 like a Phantom. I’m with SoCal it’s likely a power tube issue or something is hanging up slowing the hammers operation. Could be the sear sear slot or something is mis alined those front block style Carters can be a pain to aline. I usually leave them a lil loose wiggle them around till you get the right feel in the action and tighten them down. Issue could arise where the mount screws are stripped enough that it won’t stay. In this case I drill the threads out to except CCI phantom stainless threaded inserts and red lock them in.

[Walker]

The sear being unable to latch, when the TPC was adjusted all the way inward, was caused by the powertube being too long. When the TPC was adjusted all the way in, the tip of the powertube was hitting the inside of the front of the TPC not allowing the bolt to come back far enough to latch the sear. When cocking the gun, the hammer stopped 3/32" away from the shoulder on the powertube. I trimmed 5/32" off the powertube to resolve that issue. I adjusted the TPC all the way in to test, the sear latches with no issues. Also, Carter's hammer has a lip on the inside (right at the back) that stops the TPC from exiting through the rear. Unlike a Phantom which can pass all the way through.

As for velocity, I'm using a red main spring and a very light valve spring. With my 650psi output HPA tank, it is shooting 238-246 fps with the TPC adjusted all the way in. Still a work in progress, I need to get a better selection of springs. And make me a Carter velocity adjust tool..... And maybe some different powertubes......

I was the original seller, my bad for not doing more complete testing before I sent it out.

[Socalpumpballer]

What kind of power tube was it? Carters usually do well with a cut down phantom power tube. I wouldn’t try to squeeze velocity out with a heavy mainspring fully compressed. It’s a good way to snap the power tube

[Walker]

Phantom on top.....





Inside diameter:
- Phantom: .172
- Carter: .145

Diameter where it enters the valve cap:
- Phantom: .248
- Carter: .274

Diameter of tube forward of collar:
- Phantom: .248
- Carter: .235

Length of tube, forward of collar:
- Phantom: 1.386
- Carter: 1.520


The Phantom power tube will work, but there is a bit of slop due to the difference in diameters. Changing just the powertubes causes a velocity drop when the Phantom tube is used.

All three power tubes:


The Lapco is very similar to the one for the Phantom, it is just longer.

[Chuck E Ducky]

Curious how thees compare to a Lapco Ghost.

[RedLeaderSB]

Does the phantom valve body nut thread in? I have a Carter with phantom power tubes in it, but I don’t recall if I had to make a bee valve body to match the nut or not.

[Walker]

The Phantom nut will not thread into the Carter. The Carter takes a larger diameter.

[Walker]

Some more twiddling....

1. Carter powertube, heavier than red main spring, stock silver valve spring, TPC set to middle of run, 800psi output 13/3000 with a fresh fill. Shooting 212 to 220fps....
2. No change to parts in step 1, TPC one more turn in, shooting 220 to 228fps.
3. Change just the valve spring to a very light one, shooting 238-241fps.
4. Change tank only to a 625psi output, charged to 3000psi, expected the velocity to drop, and it didn't! It went up to 248-255psi....
5. Mounted a 12-gram changer, stuck in a twelvie, charged it up, no leaks. Expected a change, but not a great one. Wrong again! <shakes head> Velocity dropped to 215-217, very consistent over 10 shots.

Am I going to have to put a regulator on this and find the sweet spot? Yeeshhhh.....

[Socalpumpballer]

So it looks like the issue could be the cup seal side of the power tube. I’m thinking the same way you had a bottoming out issue with the front the same is happening in the back. Does your valve body compensate for the longer back end of the power tube/ cup seal assembly? Could be that standard nelson springs are causing the valve not to open properly. Also I’ve never seen a Carter power tube with such small holes maybe flow being choked there as well especially when not using straight co2.

the next step is to unscrew the valve body nut and see where the inlet holes line up when the power tube is in the complete open position. See if there is any under or over travel. The inlet holes should just barely pass the edge of the valve nut. Also completely assemble the valve and see how far you can push the power tube with your thumb against the valve spring. See if it’s bottoming out too early before the valve has a chance to open properly

[Walker]

Thanks for all the help! I appreciate it......

1. Ensured TPC was at center of travel.
2. Clipped 2 turns off the lightest spring I have.
3. Red main spring.

Inlet holes:


Powertube completely closed with spring installed:


Results (3 different tanks):

Low = Velocity of the slowest shot
High = Velocity of the highest shot
Average = Average velocity of all shots
Extreme Spread = High velocity minus low velocity
Standard Deviation = Standard deviation of the string of shots
Ten shots taken on all strings


1. HPA, 800psi output, First Strike 13/300
- Low: 238.3
- High: 266.2
- Average: 252
- Extreme spread: 27.88
- Standard deviation: 8.83

2. HPA, 625psi output, Riva 68/4500
- Low: 242.8
- High: 262.5
- Average: 251.6
- Extreme spread: 19.68
- Standard deviation: 6.08

3. Co2, 12-gram
- Low: 216.2
- High: 236.2
- Average: 227.5
- Extreme spread: 19.98
- Standard deviation: 6.24

Note: The port between the air chamber and the valve chamber on the Carter is 3/32", that on the Phantom is 3/16".

[Walker]

Mods: Please close this post, I will pick up the troubleshooting in the Carter Machine section. I should have done that in the first place.

[Painthappy]

Your wish has been granted. You now have two left.