Vulcan .25 help

[KYAirgunner]

I have a gen 2 vulcan that I took apart today and the screw near the breach that seats the barrel isn't long enough to seat the barrel. Am I missing a piece that goes between the barrel and the screw? The screw wasnt even long enough to get to the barrel. I'm pretty sure the .22s are a little different than the .25. Help would be appreciated.

MOD EDIT: MOVED TO PCP SECTION

 

[clgraham82]

I think...some have a set screw below the cap screw that just serves to help center the barrel, the cap screw keeps from getting blowback shooting out the hole into your cheek. The two bands that hold the air tube and the barrel are what keep the barrel in place...at least that's how I understand it.

 

[KYAirgunner]

So is it possible to shoot it without the set screw? I looked through the hole with a flashlight until I could see the indent in the barrel then I tightened up the clamps. Will that work or should I find a set screw for it.

 

[MrAirgun]

AFAIK the .25 doesn't have a set screw for the barrel. Neither of the two I bought had. They just have a torx bolt covering the hole which is refitted after visual alignment.

I think it's to help accuracy throughout cylinder pressure changes.

 

[clgraham82]

My .25 didn't come with a set screw just the cap screw and I haven't had any problems with shooting it that way. I just have to make sure the indent is lined up with the hole when I put the barrel back or the transfer port will also be misaligned.

 

[KYAirgunner]

Okay thanks guys mine doesn't have the set screw either just the cap screw. I thought i was missing a piece because i saw that some of the .22 had one. One thing I did learn about centering the barrel is that if you push it to far back your magazine wont go in. But its working now, thanks.

 

[marius1691]

Hallo guys.
This was veri good post.
after i read i have it, i decide to check my gun. and i fig it out, that my port was not aline, so i have put it strait and get 13 f more speed.
i have remove airtub before and i didnt check my transfer port when i tite rings back, so my barrel move a bit.
SO TIPS for 25 kal. if you release screws who holding airtub and barrel after tite it back its good to check transfer port.

 

[KYAirgunner]

"marius1691"Hallo guys.
This was veri good post.
after i read i have it, i decide to check my gun. and i fig it out, that my port was not aline, so i have put it strait and get 13 f more speed.
i have remove airtub before and i didnt check my transfer port when i tite rings back, so my barrel move a bit.
SO TIPS for 25 kal. if you release screws who holding airtub and barrel after tite it back its good to check transfer port.

Glad to here you got your gun fixed marius.

 

[marius1691]

Thanks KYAirgunner.
i steel working whith it .
i have get veri good accuracy 266 m/s and it was stabil, but after 150 shots it get down to 262.
si this is normal?
How is the best find stabil speed- find maximum speed and then go back slowly, or begin with low and race it up slowly until it gets stabil?
Thanks for coments.

 

[KYAirgunner]

I think one of the best ways to get it as accurate as you can is when you shoot your paper do 5 shot groups then do like half a turn on your spring tension adjuster and keep shooting groups and adjusting until you see better accuracy. Once you get it adjusted to its most accurate point you can chronograph it and see what speed your at. I am currently getting about a 15 to 20 Feet per second spread I'm not sure what that is in mps. I translated your m\s to fps and it is about 20 fps spread so I think that is pretty normal for a vulcan. If you are getting good accuracy you might want to leave where its at or you can experiment with different speed and see if accuracy becomes better.

 

[marius1691]

steal working on it.
i get good groups , but thay mooving.
i shoot in gun yesterday and today it shoot about 1 inch to the right at 50m. and like that is often.
Do i need to have patience and keep shooting and hope that it stabilisate, or kyp try ing adjust hummer spring and find better point?
Thanks for comments!

 

[KYAirgunner]

If the gun is grouping well it might not be the gun that is the problem with your groups shifting. It could be the quality of the scope you have or if your parallax is not set to the correct focal point. You can also try making sure the screws in your stock are tight. If you can't the rifle to the left or the right to far that can also cause groups to shift. it might also be the pellets shifting but if it keeps grouping consistently that might not be the problem. Good luck I hope you find your problem.