Pellets getting caught.

[chinaboy]

I've been breaking in my 1377.  It has a crosman steel breech and a Mellon .22  20" barrel.  I've only used Gamo pellets so far.  About every 5-10 shots seem to get stuck in the barrel.   I'll re-cock the hammer and fire and then the pellet comes out yet extremely off target.   When I look at the pellets it looks like there is a flat edge on the pellet's skirt that wasn't there before shooting.   

I think either the pellets are crappy and too large or the barrel has an imperfection around the port.  The pellets do seem to need to be stuffed into the barrel with the probe.  Anyone else have this problem? 

[arkmaker †]

Something is really messing you up here! Take a look at the crown and make sure it hasn't been damaged. The other place I would look is the transfer port opening of the barrel. You will need to take the barrel off to see it. If you have a small round or half round jewelers file, run it in over the inside TP hole.

Rich

[1377x]

do you think running a qtip through the loading port would tell you if you had burr at the transfer port

[storsy]

Maybe check yor barrel is 100% aligned, and set far enough into the breech, to make sure the transfer port sleeve is flush.
Just a thought.
I had similar nicks out of pellet heads when i first changed breech and barrel, went away after i gently tapped the barrel into the breech.
Only marks i get since doing that are rifling marks.

PS, don't use a hammer, use the rubber handle instead, to avoid causing any barrel damage.

[arkmaker †]

Yep, more good thought to try out. If there is a gap betwee the breech and barrel  the pellet could cock on you there.
A q-tip will check for burrs.

OH yeah...did you by chance open up the diameter of the TP?? That will cause the pellet to fall into the hole and cock as well.

[chinaboy]

All good suggestions!  I just took a couple of shots and noticed something.  My breech has been wiggling a little and I had been planning to tighten the screw sooner or later when I felt like taking off the scope.  So the last shot I took today I could see the bottom rubber seal from the transfer port had cracked and shot out.  So, I took a tissue and laid it on top of the breech and took a couple blank shots.  Wow, there was a lot of air leaking.  Hmm. 

Anyway, I took the thing apart which automatically makes me want to purchase some parts and modify something greater the current task at hand.  The barrel crown is sweet and looks great.   The barrel's port was smooth as I twirled a q-tip around it without a snag of cotton.  So that didn't seem to be the problem.  The mellon barrel is worth the expense in my opinion.  I didn't check the barrel to breech gap as I just ripped the barrel out. 

Since I broke that o-ring rubber seal on the transfer port I want to get both a top and bottom seal for it.  I'm also going to order a new probe as the current one is stock.  I was thinking the extended hollow Gmac probe would be sweet.  I have a couple tiny magnets to glue to the back of what ever probe I get.   I'm also eye-balling a steel safety, a trigger, scope and shroud when I get the cash. 

Where should I get theses seals?  Crosman.  Maybe Gmac if I order a probe. 

I'm still a new to this, does the transfer port piece have the larger portion pointing up or down if you know what I mean.  Maybe I had this piece in wrong and this led to the o-ring cracking.  I did notice the valve port is more to the left of the tube port and I think this would hinder air flow and also add the a cracked o-ring  too.

[quickster47 †]

Crosman is usually always a good source for your OEM parts.  GMAC is also well stocked.

Carl

[JEBert]

I'm still a new to this, does the transfer port piece have the larger portion pointing up or down if you know what I mean.  Maybe I had this piece in wrong and this led to the o-ring cracking.  I did notice the valve port is more to the left of the tube port and I think this would hinder air flow and also add the a cracked o-ring  too.

The long end of the transfer port goes up into the barrel.
The port in the valve can be adjusted by tightening or loosening the valve body a little.  It is sealed with an O-ring so it doesn't have to be very tight.  I usually adjust it during installation by by putting the trigger frame screw to hold the front half in place in the tube and use a punch that fits the valve port and turn the back half until the port lines up with the hole in the tube before installing the breech and barrel.
Cheers,

[1377x]

if you can cut the tp gasket in half and have a usable half
it makes a great top seal for the tp

[quickster47 †]

Don't forget to take a look at the Brutuz 'Evo' mod thread as it is full of good information on the top seal.  I did what he suggested and it worked great.

Carl

[chinaboy]

While working I put a tiny o-ring from a lighter on the transfer port top.  I'll see how this works for now.  The gasket also cracked completely so I wasn't able to cut it.  I think I'm going to get the gasket from Crosman along with a few parts I don't really need but would mind having.   I've read that Brutuz Evo mod and still am unsure what he did.  Did he cut a piece of tube to make a top gasket? 

I did align the valve properly.  When I put in the flat top valve I didn't even notice or know that I could center the valve port.  Its just one of those things you pick up as you go.

I took a look at Gmac's site and think the extended hollow probe should be $30 with shipping.  Or so I think.  So I want to grab that and glue a magnet onto this when I put my 1377 back together. 

[quickster47 †]

The small o-ring from the lighter is quite similar to the Evo mod so you should be good to go.

Personally, I like the extended hollow probe and hopefully it will work out for you also.  No real significant power gains but very consistent pellet placement and that leads to more accurate shots.

Carl

[tookiebrookie]

I just added a Crosman 2240 breech and 24" barrel to my 1377.  Had a heck of a time with the steel sleeve.  It wouldn't stay down where it belonged in the port, so the barrel wouldn't go all the way into the breech.  Had to remove the breech screw and loosen the rear sight screw.  Lifting the breech from the tube, I pushed the barrel all the way back into the breech and lowered the barrel port & breech down onto the sleeve and tightened everything up.
I don't know if it supposed to go this way, or if the sleeve usually sits down in the port enough for the barrel to slide back.  If the sleeve usually sits too high to slide the barrel back, I haven't read about it and its not in the instructions.  Anybody else had this problem?

[1377x]

I just added a Crosman 2240 breech and 24" barrel to my 1377.  Had a heck of a time with the steel sleeve.  It wouldn't stay down where it belonged in the port, so the barrel wouldn't go all the way into the breech.  Had to remove the breech screw and loosen the rear sight screw.  Lifting the breech from the tube, I pushed the barrel all the way back into the breech and lowered the barrel port & breech down onto the sleeve and tightened everything up.
I don't know if it supposed to go this way, or if the sleeve usually sits down in the port enough for the barrel to slide back.  If the sleeve usually sits too high to slide the barrel back, I haven't read about it and its not in the instructions.  Anybody else had this problem?

i usually put the two pieces together before i install them. makes it a little easier

[arkmaker †]

I align the barrel port to the hole in the bottom of the breech and tighten the set screw to hold it in place. The transfer port tube is in the valve tube (sitting in the rubber flat o-ring). Then I just drop the assembled breech/barrel onto the TP tube, give it a little wiggle and put in the small breech screw in loosely and then the site screw. Go back and alternate tightening the breech screw and the site screw until snugged up. Also look at the mating between the valve tube and breech. There should be no gaps and not tilted forwards or back.

After many different tries, I find that the easiest way.

Rich